The girder rail

One of the key inventions in the world history of trams was that of the girder rail developed in 1852 by Frenchman Alphonse Loubat. It brought the tram track down to road level, avoiding accidents to pedestrians and other vehicles caused by the standard protruding rail used until then. Inspired by John Stephenson of New York, it was in Paris that Loubat built the first line of this type, for horse trams, which was inaugurated on 21 November 1853 in connection with the 1855 World Fair. On a trial basis, it ran along the banks of the Seine from the Place de la Concorde to the Pont de Sèvres in the village of Boulogne.

Horse trams

Several French cities were equipped with horse-tram networks towards the end of the 19th century. In Paris, Tramways Sud operated horse trams from 1875 to 1901. In Marseille, horse trams operated by Compagnie Générale Française de Tramways entered service in 1876 on a number of routes including the Canebière. In Strasbourg, horse tram services began in 1877.

Mechanical traction

As horse trams presented a number of disadvantages (need for several teams of horses per vehicle per day, relatively slow speed, droppings on the roadway), it was not long before various mechanical traction systems came into use. These included:

*Compressed air systems, first introduced in Nantes in 1879 with Mékarski compressed air cars operating between Doulon and the Gare Maritime. Initially there was a fleet of 22 trams, two locos and four open-topped double-deck trailers. The first line was just over 6& km long, built to standard gauge and was mostly level, running along the quays of the Loire. Mekarski trams were also operated in Paris (1887), Vichy (1895), Aix-les-Bains (1897), Saint-Quentin (1899), and La Rochelle (1901).

*Steam traction was introduced fairly widely in the 1880s and 1890s, in most cases for relatively short periods as electric trams were soon to follow. For example, the Versaille Tramway started using steam trams for the stretch to Saint-Cyr in 1889 before electrification in 1895. In Strasbourg, there were steam trams from 1879 to 1899 although electrification began in 1895. Marseille’s steam trams came in 1892, shortly before their electric counterparts in 1900.

Electrification

Although Werner von Siemens demonstrated the electric tram in 1881 at the International Electical Exhibition in Paris, it was not until 1890 that the first électric tram was opened in Clermont-Ferrand, and in 1895 the Tramway de Versailles was converted from steam power to electric power. While electricity offered considerable benefits including ease of operation, many municipalities were reluctant to bring overhead cabling into their city centres. Nevertheless, over the next 15 years, well over 100 standard and small gauge electric tram networks came into operation.

Post-war closures

Most of France’s tram systems closed during the 1930s or in the post-war years. The only systems which have remained in continuous use are those in Lille, Marseille and Saint-Étienne but even these were extensively reduced in size before the recent revival.

Adapted from the Wikipedia article Trams in France, under the G. N. U. Free Documentation License. Please also see http://en.wikipedia.org/wiki

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Napoleonic Wars

In 1810, the French Empire reached its greatest extent. On the continent, the British and Portuguese remained restricted to the area around Lisbon and to besieged Cadiz. Napoleon married Marie-Louise, an Austrian Archduchess, with the aim of ensuring a more stable alliance with Austria and of providing the Emperor with an heir. As well as the French Empire, Napoleon controlled the Swiss Confederation, the Confederation of the Rhine, the Duchy of Warsaw and the Kingdom of Italy. Territories allied with the French included: the Kingdom of Spain, the Kingdom of Westphalia, the Kingdom of Naples, the Principality of Lucca and Piombino, and Napoleon’s former enemies, Prussia and Austria.

The French invasion of Russia of 1812 was a turning point, which reduced the French and allied invasion forces (the Grande Armée) to a tiny fraction of their initial strength and triggered a major shift in European politics, as it dramatically weakened the previously dominant French position on the continent. After the disastrous invasion of Russia, a coalition of Austria, Prussia, Russia, Sweden, the United Kingdom, and a number of German States, and the rebels in Spain and Portugal united to battle France in the War of the Sixth Coalition. Two-and-a-half million troops fought in the conflict and the total dead amounted to as many as two million. This era included the battles of Smolensk, Borodino, Lützen, Bautzen, and the Dresden. It also included the epic Battle of Leipzig in October, 1813 (also known as the Battle of Nations), which was the largest battle of the Napoleonic wars, which drove Napoleon out of Germany.

The final stage of the War of the Sixth Coalition, the defense of France in 1814, saw the French Emperor temporarily repulse the vastly superior armies in the Six Days Campaign. Ultimately, the Allies occupied Paris, forcing Napoleon to abdicate and restoring the Bourbons. Napoleon was exiled to Elba.

Napoleon shortly returned from exile, landing in France on March 1, 1815, marking the War of the Seventh Coalition, heading toward Paris while the Congress of Vienna was sitting. On 13 March, seven days before Napoleon reached Paris, the powers at the Congress of Vienna declared him an outlaw; four days later the United Kingdom, Russia, Austria and Prussia, members of the Seventh Coalition, bound themselves to put 150,000 men each into the field to end his rule. This set the stage for the last conflict in the Napoleonic Wars, the defeat of Napoleon at the Battle of Waterloo, the restoration of the French monarchy for the second time and the permanent exile of Napoleon to the distant island of Saint Helena, where he died in May 1821.

Spanish American wars of independence

Spain in the 1810s was a country in turmoil. Occupied by Napoleon from 1808 to 1814, a massively destructive “war of independence” ensued, driven by an emergent Spanish nationalism. Already in 1810, the Caracas and Buenos Aires juntas declared their independence from the Bonapartist government in Spain and sent ambassadors to the United Kingdom. The British blockade against Spain had also moved most of the Latin American colonies out of the Spanish economic sphere and into the British sphere, with whom extensive trade relations were developed. The remaining Spanish colonies had operated with virtual independence from Madrid after their pronouncement against Joseph Bonaparte.

The Spanish government in exile (Cádiz Cortes) created the first modern Spanish constitution. Even so, agreements made at the Congress of Vienna (where Spain was represented by Pedro Gómez Labrador, Marquis of Labrador) would cement international support for the old, absolutist regime in Spain.

King Ferdinand VII, who assumed the throne after Napoleon was driven out of Spain, refused to agree to the liberal Spanish Constitution of 1812 on his accession to the throne in 1814. The Spanish Empire in the New World had largely supported the cause of Ferdinand VII over the Bonapartist pretender to the throne in the midst of the Napoleonic Wars. When Ferdinand’s rule was restored, these juntas were cautious of abandoning their autonomy, and an alliance between local elites, merchant interests, nationalists, and liberals opposed to the abrogation of the Constitution of 1812 rose up against the Spanish in the New World.

The arrival of Spanish forces in the American colonies began in 1814, and was briefly successful in restoring central control over large parts of the Empire. Simon Bolivar, the leader of revolutionary forces in New Granada, was briefly forced into exile in British-controlled Jamaica, and independent Haiti. In 1816, however, Bolivar found enough popular support that he was able to return to South America, and in a daring march from Venezuela to New Granada (Colombia), he defeated Spanish forces at the Battle of Boyaca in 1819, ending Spanish rule in Colombia. Venezuela was liberated June 24, 1821 when Bolivar destroyed the Spanish army on the fields of Carabobo on the Battle of Carabobo. Argentina declared its independence in 1816 (though it had been operating with virtual independence as a British client since 1807 after successfully resisting a British invasion). Chile was retaken by Spain in 1814, but lost permanently in 1817 when an army under Jose de San Martin, for the first time in history, crossed the Andes Mountains from Argentina to Chile, and went on to defeat Spanish royalist forces at the Battle of Chacabuco in 1817.

Spain would also lose Florida to the United States during this decade. First, in 1810, the Republic of West Florida declared its independence from Spain, and was quickly annexed by the United States. Later, in 1818, the United States invaded Florida, resulting in the Adams-Onís Treaty, wherein Spain ceded the rest of Florida to the United States.

In 1820, Mexico, Peru, Ecuador, and Central America still remained under Spanish control. Although Mexico had been in revolt in 1811 under Miguel Hidalgo y Costilla, resistance to Spanish rule had largely been confined to small guerrilla bands in the countryside. King Ferdinand was still dissatisfied with the loss of so much of the Empire and resolved to retake it. A large expedition was assembled in Cadiz with the aim of reconquest. However, Ferdinand’s plans would be disrupted by the Spanish Civil War of 1820-1823, and Ferdinand was eventually forced to give up all of the New World colonies, except for Cuba and Puerto Rico.

War of 1812

In response to multiple grievances, the United States declared war on Britain in the War of 1812. The grievances included humiliating the U.S. in the “Chesapeake incident of 1807, continued British impressment of American sailors into the Royal Navy, restrictions on trade with France, and arming hostile Indians in Ohio and the western territories.

* June 1, 1812 – War of 1812: U.S. President James Madison asks the U.S. Congress to declare war on Great Britain.

* June 18, 1812 – The War of 1812 begins between the United States and the British Empire.

* February 11, 1813 – Fort Meigs: Leftwich is not successful, and when he leaves, Major Amos Stoddard assumes the command of the post.

* April 8, 1813 – Colonel James Ball arrives at Fort Meigs with 200 dragoons.

* March 27, 1814 – War of 1812 – Battle of Horseshoe Bend: In northern Alabama, United States forces under General Andrew Jackson defeat the Creek Indians.

The war ended in a draw after bitter fighting that lasted until January 8, 1815, during the Battle of New Orleans. The war was a major loss for Native American tribes in the Northwest and Southeast who had allied themselves with Britain and were defeated on the battlefield.

1804-1813 Russo-Persian War

The 1804-1813 Russo-Persian War was one of the many wars between the Persian Empire and Imperial Russia, and was well underway at the beginning of the decade. In 1810, the Persians scaled up their efforts late in the war, declaring a holy war on Imperial Russia. However, Russia’s superior technology and tactics ensured a series of strategic victories. Even when the French were in occupation of the Russian capital Moscow, Russian forces in the south were not recalled but continued their offensive against Persia, culminating in Pyotr Kotlyarevsky’s victories at Aslanduz and Lenkoran, in 1812 and 1813 respectively. Upon the Persian surrender, the terms of the Treaty of Gulistan ceded the vast majority of the previously disputed territories to Imperial Russia. This led to the region’s once-powerful khans being decimated and forced to pay homage to Russia.

Concert of Europe

By 1815, Europe had been almost constantly at war. During this time, the military conquests of France had resulted in the spread of liberalism throughout much of the continent, resulting in many states adopting the Napoleonic code. Largely as a reaction to the radicalism of the French Revolution, the victorious powers of the Napoleonic Wars resolved to suppress liberalism and nationalism, and revert largely to the ”status quo” of Europe prior to 1789.

The result was the Concert of Europe, also known as the “Congress System”. It was the balance of power that existed in Europe from 1815 until the early 20th century. Its founding members were the United Kingdom, Austrian Empire, Russian Empire and Kingdom of Prussia, the members of the Quadruple Alliance responsible for the downfall of the First French Empire; in time France became established as a fifth member of the concert. At first, the leading personalities of the system were British foreign secretary Lord Castlereagh, Austrian chancellor Klemens Wenzel, Prince von Metternich and Tsar Alexander I of Russia.

The Kingdom of Prussia, Austrian Empire and Russian Empire formed the Holy Alliance with the expressed intent of preserving Christian social values and traditional monarchism. Every member of the coalition promptly joined the Alliance, save for the United Kingdom.

Among the meetings of the Powers in the latter part of the 1810s were the Congresses of Vienna (1814–1815), Aix-la-Chappelle (1818), and Carlsbad (1819).

Gunboat War

* Gunboat War (1807–1814)

** March 27, 1811 – Battle of Anholt: The British navy defeats Denmark.

Other political events=

Australia

* Black War (1804–1835)

Asia

* 1810: Ching Shih and Chang Pao surrender their pirate fleet to the Chinese government.

* 1810: Russia acquires Sukhumi through a treaty with the Abkhazian dukes, and declares a protectorate over the whole of Abkhazia.

* Russo-Turkish War

** May 28, 1812 – Russian Field Marshal Mikhail Kutuzov signs the Treaty of Bucharest, ending the Russo-Turkish War, 1806-1812 and making Bessarabia a part of Imperial Russia.

* October 31, 1817 – Emperor Ninkō accedes to the throne of Japan.

* 1818: The Third Anglo Maratha War is fought between the Marathas and the British East India Company troops resulting in the defeat of the Peshwa, the breakup of the Maratha Empire, and the loss of Maratha independence to the British as they annexed Central India. The last Peshwa is exiled to Bithur near Kanpur. His adopted son and heir Nana Saheb was one of the principal revolutionary commanders in the Indian Mutiny.

Europe

* August 21, 1810 – Jean-Baptiste Bernadotte, Marshal of France, is elected Crown Prince of Sweden by the Swedish Riksdag of the Estates.

* September 26, 1810 – A new Act of Succession is adopted by the Riksdag of the Estates and Jean Baptiste Bernadotte becomes heir to the Swedish throne.

* October 12, 1810 – First Oktoberfest: The Bavarian royalty invites the citizens of Munich to join the celebration of the marriage of Crown Prince Ludwig of Bavaria to Princess Therese of Saxe-Hildburghausen.

* February 5, 1811 – British Regency: George, Prince of Wales becomes Prince Regent because of the perceived insanity of his father, King George III of the United Kingdom.

* September, 1811 – Nathan of Breslov leads the first annual Rosh Hashana kibbutz (pilgrimage) of Breslov Hasidim to the grave of Rabbi Nachman of Breslov in Uman, Ukraine.

* January 1, 1812 – The ”Allgemeines bürgerliches Gesetzbuch” (the Austrian civil code) enters into force in the Austrian Empire.

* May 11, 1812 – John Bellingham assassinates British Prime Minister Spencer Perceval in the lobby of the British House of Commons.

* July 18, 1812 – Russia’s Patriotic War, 1812 – Battle of Klyastitsy: Kulnev defeats Oudinot but sustains a mortal wound.

* October 18–October 20, 1812 – Second Battle of Polotsk – Russia

* December 30: Convention of Tauroggen was signed.

* 1812: The capital of Finland is moved from Turku to Helsinki.

* November 10: A general election in the United Kingdom sees victory for the Tory Party under Robert Jenkinson, 2nd Earl of Liverpool.

* 1813: George Hamilton-Gordon serves as ambassador extraordinaire in Vienna.

* 1813: Following the death of his father Wossen Seged, Sahle Selassie arrives at the capital Qundi before his other brothers, and is made Meridazmach of Shewa.

* Norway in 1814

** January 14, 1814 – Denmark cedes Norway to Sweden in exchange for west Pomerania, as part of the Treaty of Kiel.

** February 11, 1814 – Norway’s independence is proclaimed, marking the ultimate end of the Kalmar Union.

** April 12, 1814 – The Royal Norwegian Navy is re-established.

** May 17, 1814 – The Constitution of Norway is signed and the Danish Crown Prince Christian Frederik is elected King of Norway by the Norwegian Constituent Assembly.

* May 3, 1814 – The Duke of Provence, the future Louis XVIII of France, returns to Paris.

* May 17, 1814 – The occupation of Monaco changes from French to Austrian hands.

* May 30, 1814 – The First Treaty of Paris is signed returning France’s borders to their 1792 extent. Napoleon I of France is exiled to Elba on the same day.

* August 12, 1814 – In England, the last hanging under the Black Act is carried out, of William Potter for cutting down an orchard (even the judge petitioned for reprieve).

* August 13, 1814 – The Anglo-Dutch Treaty of 1814 is signed.

* January 3, 1815 – Austria, Britain, and Bourbon-restored France form a secret defensive alliance treaty against Prussia and Russia.

* March 15, 1815 – Joachim Murat, King of Naples declares war on Austria in an attempt to save his throne, starting the Neapolitan War.

* March 16, 1815 – William I becomes King of the Netherlands.

* April 23, 1815 – The Second Serbian Uprising against Ottoman rule takes place in Takovo, Serbia. By the end of the year Serbia is acknowledged as a semi-independent state; the ideals of the First Serbian Uprising have thus been temporarily achieved.

* May 3, 1815 – Battle of Tolentino: Austria defeats the Kingdom of Naples, which quickly ends the Neapolitan War. Joachim Murat, the defeated King of Naples, is forced to flee to Corsica and is later executed.

* 1815: In Britain, use of the pillory is limited to punishment for perjury.

* January 1, 1816 – Tsar Alexander I of Russia signs an order for the expulsion of the Jesuits from the Russian Empire.

* March 25, 1816 – Friedrich Karl Ludwig, Duke of Schleswig-Holstein-Sonderburg-Beck dies and is succeeded by the later Friedrich Wilhelm, Duke of Schleswig-Holstein-Sonderburg-Glücksburg, his son and founder of the Schleswig-Holstein-Sonderburg-Glücksburg.

* 1816: The Senate of Finland is established.

* 1816: The Ottomans grant Serbia local autonomy.

* April 3, 1817 – Princess Caraboo appears in Almondsbury in Gloucestershire, England.

* May 11, 1818 – Charles XIV of Sweden-Norway is crowned king of Sweden.

* September 7, 1818 – Carl III of Sweden-Norway is crowned king of Norway, in Trondheim.

* September 23, 1818 – Border markers are formally installed for the European territory of Moresnet.

*September 20, 1819 – The Carlsbad Decree is issued throughout the German Confederation.

Africa

* 1810: Amadou Lobbo initiates his jihad in present-day Mali.

* March 1, 1811 – Citadel Massacre: Egyptian ruler Mohammed Ali kills the last Mamluk leaders.

* 1816: Banjul, capital of The Gambia, is founded as a trading post, and named Bathurst.

* August 27, 1816 – Bombardment of Algiers: Various European Allie ships force the Dey of Algiers to free Christian slaves.

* 1818: Shaka starts to rule.

* Mtetwa Empire Expansion

North America

* May 1, 1810 – Macon’s Bill No. 2 becomes law.

* June 4, 1810 – The Society in Dedham for Apprehending Horse Thieves is founded in Dedham, Massachusetts.

* 1811: The Red River Colony is founded in Manitoba, Canada.

* March 22, 1811 – The Commissioners’ Plan of 1811 for Manhattan is presented.

* November 6, 1811 – Battle of Tippecanoe: American troops led by William Henry Harrison defeat the Native American chief Tecumseh.

* February 11, 1812 – Massachusetts governor Elbridge Gerry invents gerrymandering.

* April 4, 1812 – U.S. President James Madison enacts a 90-day embargo on trade with the United Kingdom.

* April 30, 1812 – Louisiana is admitted as the 18th U.S. state.

* June 4, 1812 – Following Louisiana’s admittance as a U.S. state, the territory by that name is renamed the Missouri Territory.

* October, 1812 – The capital of the Commonwealth of Pennsylvania, United States is permanently moved from Lancaster to Harrisburg.

* November 5, 1812 – James Madison defeats DeWitt Clinton in the U.S. presidential election.

* December 15, 1814 – The Hartford Convention is convened by members of the American Federalist Party.

* February – The Hartford Convention arrives in Washington DC.

* August 24, 1816 – The Treaty of St. Louis is signed in St. Louis, Missouri.

* November 6, 1816 – James Monroe defeats Rufus King in the U.S. presidential election.

* December 11, 1816 – Indiana is admitted as the 19th U.S. state.

* 1816: The Second Bank of the United States obtains its charter.

* The Era of Good Feelings (1816–1823/1824) in the U.S.

* March 3

**President James Madison vetoes John C. Calhoun’s Bonus Bill.

**U.S. Congress passes law to split the Mississippi Territory, after Mississippi drafts a constitution, creating the Alabama Territory effective in August.

* March 4, 1817 – James Monroe succeeds James Madison as President of the United States of America.

* April 29, 1817 – The Rush-Bagot Treaty is signed.

* August 15, 1817 – By act of the U.S. Congress (March 3), the Alabama Territory is created by splitting the Mississippi Territory in half, on the day the Mississippi constitution is drafted, 4 months before Mississippi becomes a U.S. state.

* November 20, 1817 – The first Seminole War begins in Florida.

* December 10, 1817 – Mississippi is admitted as the 20th U.S. state, formerly the Mississippi Territory.

* April 4, 1818 – The U.S. Congress adopts the flag of the United States as having 13 red and white stripes and one star for each state (20 stars) with additional stars to be added whenever a new state is added to the Union.

* August 1, 1818 – Separate Topographical Bureau of the War Department.

* October 20, 1818 – The Treaty of 1818 between the U.S. and the United Kingdom establishes the northern boundary as the 49th parallel from the Lake of the Woods to the Rocky Mountains, also creating the Northwest Angle.

* December 3, 1818 – Illinois is admitted as the 21st U.S. state.

*February 2, 1819 – The Supreme Court under John Marshall rules in favor of Dartmouth College in the famous ”Dartmouth College v. Woodward” case, allowing Dartmouth to keep its charter and remain a private institution.

*March 6, 1819 – ”McCulloch v. Maryland”: The U.S. Supreme Court rules that the Bank of the United States is constitutional.

* 1819: The ‘Ai Noa Movement takes power in Hawaii.

* The city of Fernandina of Jagua (later Cienfuegos City) is founded in Cuba.

*December 14, 1819 – Alabama is admitted as the 22nd U.S. state.

South America

* 1814: Guyana is transferred from the Netherlands to Britain; it is renamed ”British Guiana”.

* August 22, 1817 – The city of Araraquara, Brazil is founded.

*The Spanish colony of New Granada declares independence as the Republic of Gran Colombia under President Simón Bolívar (1800–1900)* Stars the period of Latin American revolutions. Several states declare their independence from Spain.

* 1817: The Pernambucan Revolt breaks out in Brazil.

Adapted from the Wikipedia article 1810s, under the G. N. U. Free Documentation License. Please also see http://en.wikipedia.org/wiki

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* 1991 Development started.

* 1993 Polyhedra 1.0: first commercial release of an in-memory Relational DBMS (RDBMS).

* 1995 Ported to Windows and Linux.

* 1996 Polyhedra 2.0: added hot standby configurations for use in applications needing high availability. First port to an RTOS (pSOS)

* 1997 Polyhedra 3.0: new in-memory data storage engine, for improved space and time efficiency.

* 1999 Polyhedra 3.1: adds new data types, ODBC API. OSE port.

* 2001 Polyhedra 4.0: JDBC support, additional index type, read-only replicas, multi-threading.

* 2002 Polyhedra 4.1: client–server comms overhauled for substantial performance improvements, especially for client apps using the ODBC API (now deemed the ‘native’ API for all platforms).

* 2003 Polyhedra 5.0: UNICODE, schema migration (SQL ‘ALTER TABLE’).

* 2004 Polyhedra 6.0: 64-bit support re-introduced, for Linux and Solaris. (It previously had been available on DEC Alpha under Digital UNIX until usage of that platform generally died out.) Polyhedra64 has subsequently been ported to Windows x64, AIX.

* 2006 Polyhedra FlashLite introduced, based on a fork of the Polyhedra IMDB code base.

* 2007 Polyhedra 7.0: Polyhedra IMDB and Polyhedra FlashLite code bases unified, for ease of support and greater commonality of features. Also, enhanced resource management and multi-threading.

* 2008 Polyhedra 8.0: Polyhedra FlashLite now supports hot standby configurations for use in applications needing high availability, in a similar way to Polyhedra IMDB. Polyhedra 8.1 added Linux/MIPS support, the ability to monitor active queries, and enhancements to the historian.

2009 Polyhedra 8.2: Linux ODBC drivers and IPv6

2010 Polyhedra 8.3: Some SQL enhancements and streaming output from historian

Adapted from the Wikipedia article Polyhedra DBMS, under the G. N. U. Free Documentation License. Please also see http://en.wikipedia.org/wiki

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In Unix-like operating systems, TUIs are often constructed using the terminal control library ”curses”, or ”ncurses”, a mostly compatible library.

The advent of the ”curses” library with Berkeley Unix created a portable and stable API for which to write TUIs. The ability to talk to various text terminal types using the same interfaces led to more widespread use of “visual” Unix programs, which occupied the entire terminal screen instead of using a simple line interface. This can be seen in text editors such as vi, mail clients such as pine or mutt, system management tools such as SMIT, SAM, FreeBSD’s Sysinstall and web browsers such as lynx. Some applications, such as w3m, as well as older versions of pine and vi use the less-capable termcap library, performing many of the functions associated with curses within the application.

In addition, the rise in popularity of Linux brought many former MS-DOS users to a Unix-like platform, which has fostered an MS-DOS influence in many TUIs. The program minicom, for example, is modeled after the popular MS-DOS program Telix. Some other TUI programs, such as the Twin desktop, were ported over.

The free software program GNU Screen provides for managing multiple sessions inside a single TUI, and so can be thought of as being like a window manager for text-mode interfaces.

The proprietary Mac OS X text editor BBEdit includes a ‘shell worksheet’ function that works as a full-screen shell window.

Adapted from the Wikipedia article Text user interface, under the G. N. U. Free Documentation License. Please also see http://en.wikipedia.org/wiki

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OSSEC has a very strong log analysis engine, being able to correlate and analyze logs from multiple devices and formats. The following are currently supported:

* Unix-only:

** Unix PAM

** sshd (OpenSSH)

** Solaris telnetd

** Samba

** Su

** Sudo

* FTP servers:

** ProFTPd

** Pure-FTPd

** vsftpd

** Microsoft FTP Server

** Solaris ftpd

* Mail servers:

** Imapd and pop3d

** Postfix

** Sendmail

** vpopmail

** Microsoft Exchange Server

* Databases:

** PostgreSQL

** MySQL

* Web servers:

** Apache HTTP Server (access log and error log)

** IIS web server (NSCA and W3C extended)

** Zeus Web Server errors log

* Web applications:

** Horde IMP

** Modsecurity

* Firewalls:

** Iptables firewall

** Solaris IPFilter firewall

** AIX ipsec/firewall

** Netscreen firewall

** Windows Firewall

** Cisco PIX

** Cisco FWSM

** Cisco ASA

* NIDS:

** Cisco IOS IDS/IPS module

** Snort IDS (snort full, snort fast and snort syslog)

* Security tools:

** Symantec AntiVirus

** Nmap

** Arpwatch

** Cisco VPN Concentrator

* Others:

** Named (BIND)

** Squid proxy

** [http://www.zeus.com/products/zxtm Zeus eXtensible Traffic Manager]

* Windows event logs (logins, logouts, audit information, etc.)

* Windows Routing and Remote Access logs

* Generic unix authentication (adduser, logins, etc.)

Adapted from the Wikipedia article OSSEC, under the G. N. U. Free Documentation License. Please also see http://en.wikipedia.org/wiki

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At the beginning of 2003, SCO claimed that there had been “misappropriation of its UNIX System V code into Linux”. However, the company refused to identify the specific segments of code, claiming that it was a secret which they would reveal only to the court. They did say that the code could be found in the SMP, RCU and a few other parts of the Linux kernel.

They later announced that they were suing IBM for $1& billion, claiming that IBM transferred SCO trade secrets into Linux. That amount later rose to $3& billion, and then again to $5 billion.

Some educated parties note that the ”USL v. BSDi” case had shown that the Unix copyrights are weak and unenforceable. SCO has not claimed patent infringement, as according to the US Patent and Trademark Office database, no AT&T or Novell patent was ever assigned to SCO. The UNIX trademark was not owned by SCO. That left arguing over trade secrets, which after some opposition, was hard to take beyond a breach of contract between SCO and IBM, and consequentially a claim only against IBM. SCO was looking for something directed at the greater Linux community, and has since explicitly dropped all trade secret claims from their case.

SCO now had little legal ground at this point and therefore began numerous legal claims and threats against many of the major names in the computer industry, including IBM, Hewlett-Packard, Microsoft, Novell, Silicon Graphics, Sun Microsystems and Red Hat.

By mid 2004, five major lawsuits had been filed

* ”SCO v. IBM”

* ”Red Hat v. SCO”

* ”SCO v. Novell” (not directly related to Linux, the suit has more to do with Unix copyrights)

* ”SCO v. DaimlerChrysler”

* ”SCO v. AutoZone”

In cases SCO publicly implied that a number of other parties have committed copyright infringement, including not only Linux developers but also Linux users.

UNIX SVRx

SCO’s claims are derived from several contracts that may have transferred UNIX System V Release 4 intellectual property assets. The UNIX IP rights originated with Unix System Laboratories (USL), a division of AT&T. In 1993, USL sold all UNIX rights and assets to Novell, including copyrights, trademarks, and active licensing contracts. Some of these rights and assets, plus additional assets derived from Novell’s development work, were then sold to the Santa Cruz Operation in 1995. The Santa Cruz Operation had developed and was selling a PC-based UNIX until 2000, when it then resold its UNIX assets to Caldera, which later changed its name to SCO Group.

Through this chain of sales, SCO claims to be the “owner of UNIX”. The validity of these claims is hotly contested by others. SCO claims copyright to all UNIX code developed by USL, referred to as SVRx, and licensing contracts originating with AT&T, saying that these are inherited through the same chain of sales. The primary document SCO presents as evidence of these claims is the “Asset Purchase Agreement”, defining the sale between Novell and the Santa Cruz Operation. SCO says that this includes all copyrights to the UNIX code base and contractual rights to the licensing base. The other parties disagree.

UNIX copyrights ownership

The status of copyrights from USL is murky, since UNIX code is a compilation of elements with different copyright histories. Some code was released without copyright notice before the Copyright Act of 1976 made copyright automatic. This code may be in the public domain and not subject to copyright claims. Other code is affected by the ”USL v. BSDi” case, and is covered by the BSD License.

Groklaw uncovered an old settlement made between Unix System Laboratories (USL) and The University of California in the case of USL v. BSDi. This settlement ended a copyright infringement suit against the University for making BSD source code freely available that USL felt infringed their copyrights. The university filed a counter suit, saying that USL had taken BSD source code and put it in UNIX without properly acknowledging the university’s copyright. This settlement muddies the question of SCO’s ownership of major parts of the UNIX source code. This uncertainty is particularly significant in regard to SCO’s claims against Linux, which uses some BSD code.

Novell challenges SCO’s interpretation of the purchase agreement. In response to a letter SCO sent to 1500 companies on May 12, 2003, Novell exchanged a series of letters with SCO beginning in May 2003, claiming that the copyrights for the core UNIX System V were not included in the asset purchase agreement and are retained by Novell. In October 2003, Novell registered those copyrights with the US Copyright Office.

In response to these challenges from Novell, SCO filed a “slander of title” suit against Novell, ”SCO v. Novell”. This claimed that Novell was interfering with their business activities by clouding the ownership of UNIX copyrights. SCO’s claim for special damages was dismissed on June 9, 2004 for “failure to specifically plead special damages.” However, SCO was given 30 days “to amend its complaint to more specifically plead special damages”. In the same ruling, the judge expressed doubt that the Asset Purchase Agreement transferred the relevant copyrights.

SCO filed an amended complaint. In late July, 2005, Novell filed an answer to SCO’s complaint, denying all of its accusations. Novell also filed its own Slander of Title counter-lawsuit against SCO. Novell has also filed claims for numerous breaches of the APA between Novell and the Santa Cruz Operation. Under the APA, Santa Cruz (and later SCO after SCO purchased Santa Cruz Operation’s Unix Business) was given the right to market and sell Unixware as a product, retaining 100% of all revenues. Santa Cruz Operation (and later SCO) also was given the responsibility of administering Unix SVR4 license agreements on behalf of Novell. When money was paid for licensing, SCO was to turn over 100% of the revenue to Novell, and then Novell would return 5% as an Administration Fee. Novell claims that SCO signed Unix SVR4 licensing agreements with Microsoft and Sun Microsystems, as well as with numerous Linux End Users for Unix IP allegedly in the Linux Kernel, and then refused to turn the money over to Novell. Novell is suing for 100% of the revenue, claiming SCO is not entitled to the 5% administration fee since they breached their contract with Novell. Novell’s counterclaims proposed asking the court to put appropriate funds from SCO into escrow until the case is resolved, since SCO’s cash is diminishing quickly.

Novell also retained the right to audit SCO’s Unix Licensing Business under the APA. Novell claims that SCO has not turned over vital information about the Microsoft, Sun and Linux End User License Agreements, despite repeated demands by Novell for them to do so. Novell, in another claim that is part of their counter suit, is asking the court to compel SCO to allow Novell to perform this audit of SCO’s Unix Business.

On August 10, 2007 Judge Dale Kimball, hearing the SCO v. Novell case, ruled that “…the court concludes that Novell is the owner of the UNIX and UnixWare Copyrights”.

License administration standing

The Novell to Santa Cruz Operation Asset Purchase Agreement also involved the administration of some 6000 standing licensing agreements between various UNIX users and the previous owners. These licensees include universities, software corporations and computer hardware companies. SCO’s claimed ownership of the licenses has become an issue in three aspects of the SCO-Linux controversies. The first was the cancellation of IBM’s license, the second was SCO’s complaint against DaimlerChrysler (see ”SCO v. DaimlerChrysler”), and the third is the derivative works claim of the ”SCO v. IBM” case.

In May 2003, SCO canceled IBM’s SVRx license to its version of UNIX, AIX. This was based on SCO’s claim of unrestricted ownership of the System V licensing contracts inherited from USL. IBM ignored the license cancellation, claiming that an amendment to the original license made it “irrevocable.” In addition, as part of the Purchase Agreement, Novell retained certain rights of control over the administration of the licenses which were sold, including rights to act on SCO’s behalf in some cases. Novell exercised one of these rights by revoking SCO’s cancellation of the IBM license. SCO disputed the validity of both of these actions, and amended its ”SCO v. IBM” complaint to include copyright infringement, based on IBM’s continued sale and use of AIX without a valid SVRx license.

In December 2003, SCO demanded that all UNIX licensees certify some items, some related to the use of Linux, that were not provided for in the license agreement language. Since DaimlerChrysler failed to respond, SCO filed the ”SCO v. DaimlerChrysler” suit in March 2004. All claims related to the certification demands were summarily dismissed by the court.

Control of derivative works

The third issue based on the UNIX licensees agreement is related to SCO’s claims of control of derivative works.

Many UNIX licensees have added features to the core UNIX SVRx system and those new features contain computer code not in the original SVRx code base. In most cases, software copyright is owned by the person or company that develops the code. SCO, however, claims that the original licensing agreements define this new code as a derivative work. They also claim that they have the right to control and restrict the use and distribution of that new code.

These claims are the basis of ”SCO v. IBM”. SCO’s initial complaint, said that IBM violated the original licensing agreement by not maintaining confidentiality with the new code, developed and copyrighted by IBM, and releasing it to the Linux project.

IBM claims that the license agreement (noted in the $Echo newsletter of April 1985) and subsequent licenses defines derivative works as the developer’s property. This leaves IBM free to do as it wishes with its new code. In August 2004, IBM filed a motion for partial summary judgment. The motion stated that IBM has the right to do as it wishes with software not part of the original SVRx code. In February 2005, the motion was dismissed as premature, because discovery was not yet complete. IBM refiled this motion along with other summary judgment motions as noted below in September 2006.

SCO allegations of copyright and trade secret violations

SCO claims that Linux infringes SCO’s copyright, trade secrets, and contractual rights. This claim is fundamental to the SCOsource program, where SCO has demanded that Linux users obtain licenses from SCOsource to be properly licensed to use the code in question. Exactly which parts of Linux are involved remains unclear as many of their claims are still under seal in the ”SCO v. IBM” lawsuit.

SCO originally claimed in ”SCO v. IBM” that IBM had violated trade secrets. But these alleged violations by IBM would not have involved Linux distributors or end users. SCO’s trade secret claims were dropped by SCO in their amended complaint.

SCO also claimed line-for-line literal copying of code from UNIX code files to Linux kernel files and obfuscated copying of code, but originally refused to publicly identify which code was in violation. SCO submitted to the court evidence of their claims under seal but much of it was excluded from the case after it was challenged by IBM as not meeting the specificity requirements to be included.

These examples have fallen into two groups. The first are segments of files or whole files alleged to originate in UNIX SVRx code such as the errno.h header file. The second group are files and materials contributed by IBM that originated with IBM development work associated with AIX and Dynix, IBM’s two UNIX products.

Each of these has a different set of issues. In order for copyright to be violated, several conditions must be met. First, the claimant must be able to show that they own the copyrights for the material in question. Second, all or a significant part of the source must be present in the infringing material. There must be enough similarity to show direct copying of material.

SVRx code allegedly in Linux

The issue of ownership of the SVRx code base was discussed above. Besides the unresolved issue of what was actually transferred from Novell to Santa Cruz Operation, there are also the portions of the SVRx code base that are covered by BSD copyrights or that are in the public domain.

SCO’s first public disclosure of what they claim is infringing code was at SCO Forum in August 2003. The first, known as the Berkeley Packet Filter, was distributed under the BSD License and is freely usable by anyone. The second example was related to memory allocation functions, also released under the BSD License. It is no longer in the Linux code base.

SCO has also claimed that code related to application programming interfaces was copied from UNIX. However, this code and the underlying standards they describe are in the public domain and are also covered by rights USL sold to The Open Group. A later claim was made to code segments related to ELF file format standards. This material was developed by the Tool Interface Standard (TIS) Committee and placed in the public domain. SCO claims that the TIS Committee had no authority to place ELF in the public domain, even though SCO’s predecessor in interest was a member of the committee.

SCO has claimed that some are violating UNIX SVRx copyrights by putting UNIX code into Linux. They may or may not have brought this claim directly in any of their cases. The IBM case is about derivative works, not SVRx code (see below). The Novell case is about copyright ownership. DaimlerChrysler was about contractual compliance statements.

The “may or may not” comes from AutoZone’s case. In AutoZone, SCO’s complaint claimed damages for AutoZone’s use of Linux. However, when objecting to AutoZone’s request for a stay pending the IBM case, SCO apparently contradicted their written complaint, claiming that the case was entirely about AutoZone copying certain libraries (outside the Linux kernel) from a UNIX system to a Linux-based system to facilitate moving an internal application to the Linux platform faster; SCO’s original complaint does not appear to mention these libraries. AutoZone denies having done this with UNIX libraries. If SCO’s oral description of their case is the correct one, then their AutoZone claim has nothing to do with the Linux kernel or the actions of any distributors.

The copyright issue is addressed directly in two of the cases. The first is by IBM in their counterclaim in ”SCO v. IBM”. The issue is central to a pending motion by IBM, stating that IBM violated no copyrights in its Linux related activities. It is also addressed by Red Hat in the Red Hat v. SCO case. Red Hat claims that SCO’s statements about infringement in Linux are unproven and untrue, damaging to them and violates the Lanham Act. Red Hat asks for an injunction to stop claims of violations without proof. They also ask for a judgment that they violated no SCO copyrights. A hearing on the IBM motion was held in September 15, 2004. Judge Kimball took the motion under advisement. The Red Hat case is on hold.

Allegations of reverse copying

”EWeek” has reported allegations that SCO may have copied parts of the Linux kernel into SCO UNIX as part of its Linux Kernel Personality feature. If true, this would mean that SCO is guilty of a breach of the Linux kernel copyrights. SCO has denied this allegation, but according to Groklaw, one SCO employee confirmed it in a deposition.

IBM code in Linux

SCO has claimed a number of instances of IBM Linux code as breaches of contract. These examples include code related to Symmetric multiprocessing (SMP), Journaled File System (JFS), Read-copy-update (RCU) and Non-Uniform Memory Access (NUMA). This code is questionably in the Linux kernel, and may have been added by IBM through the normal kernel submission process. This code was developed and copyrighted by IBM. IBM added features to AIX and Dynix.

SCO claims that they have “control rights” to this due to their licensing agreements with IBM. SCO disavows claiming that they own the code IBM wrote, rather comparing their “control rights” to an easement, rights which allow them to prohibit IBM from publicizing the code they wrote, even though IBM owns the copyrights. They base this claim on language in the original license agreement that requires non-disclosure of the code and claim that all code developed by UNIX licensees that is used with the code under license be held in confidence. This claim is discussed above at Control of derivative works.

SCO and the GPL

Before changing their name to the SCO Group, the company was known as Caldera. Caldera was one of the major distributors of Linux from 1994 to 2003. Some, like Eben Moglen, have suggested that because Caldera distributed the allegedly infringing code under the GNU General Public License, or GPL, that this act would license any proprietary code in Linux.

SCO has stated that they did not know their own code was in Linux, so releasing it under the GPL does not count. However, as late as July and August 2006, long after that claim was made, they were still distributing ELF files (the subject of one of SCO’s claims regarding SVRx) under the GPL.

SCO has also claimed, in early stages of the litigation, that the GPL is invalid and non-binding and legally unenforceable. In response, supporters of the GPL, such as Eben Moglen, claimed that SCO’s right to distribute Linux relied upon the GPL being a valid copyright license. Later court filings by the SCO group in ”SCO v. IBM” use SCO’s alleged compliance with the license as a defense to IBM’s counterclaims.

The GPL has become an issue in ”SCO v. IBM”. Under U.S. copyright law, distribution of creative works whose copyright is owned by another party is illegal without permission from the copyright owner, usually in the form of a license; the GPL is such a license, and thus allows distribution, but only under limited conditions. Since IBM released the relevant code under the terms of the GPL, it claims that the only permission that SCO has to copy and distribute IBM’s code in Linux is under the terms and conditions of the GPL, one of which requires the distributor to “accept” the GPL. IBM says that SCO violated the GPL by denouncing the GPL’s validity, and by claiming that the GPL violates the U.S. Constitution, together with copyright, antitrust and export control laws. IBM also claims that SCO’s SCOsource program is incompatible with the requirement that redistributions of GPLed works must be free of copyright licensing fees (fees may be charged for the acts of duplication and support). IBM has brought counterclaims alleging that SCO has violated the GPL and breached IBM’s copyrights by collecting licensing fees while distributing IBM’s copyrighted material.

Adapted from the Wikipedia article SCO-Linux controversies, under the G. N. U. Free Documentation License. Please also see http://en.wikipedia.org/wiki

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Early work on the psychological reality of linguistic rules.

Kennedy’s early research (much of it in collaboration with A. L. Wilkes) was concerned with the “psychological reality” of linguistic rules, a preoccupation of cognitive psychologists in the 1970s. This work made use of simple laboratory tasks involving pressing buttons to indicate whether sentence fragments were grammatical or not, or to signal the presence of a particular word in a sentence.

Kennedy, A. and Wilkes, A.L. (1968). Response-times at different positions within a sentence. ”Quarterly Journal of Experimental Psychology”, 82, 390-394.

Kennedy, A. and Wilkes, A.L. (1969). Analysis of storage and retrieval processes in memorising simple sentences. ”Journal of Experimental Psychology”, 80, 396-398.

Kennedy, A. and Wilkes, A.L. (1971). Functional Structure in sentences: a performance analysis. ”Quarterly Journal of Experimental Psychology”, 23, 214-224.

Eye movement control and reading

In 1972, Kennedy spent six months in Paris, coming into contact with members of “Groupe Regarde”, an informal network of researchers working on psychological issues relating to eye movement control and led by Arianne Levy-Schoen. On his return to Dundee, Kennedy set up an eye movement laboratory aiming to replace indirect measurement of reaction time with more direct measurements of eye movements as participants read text. Initially, the principal UK funding agency (the Social Science Research Council) saw no future in work on eye movement control and refused to fund it. The validity of the approach was eventually accepted following a series of highly influential publications from laboratories in the USA. In 1979 Kennedy secured funding and a series of papers in collaboration with Wayne S. Murray confirmed that both the duration and location of eye fixations were controlled by linguistic properties of the text being read.

Kennedy, A. and Murray, W.S. (1984). Inspection-times for words in syntactically ambiguous sentences under three presentation conditions. ”Journal of Experimental Psychology: Human Perception and Performance”, 10, 833-849.

Holmes, V.M., Kennedy, A., and Murray, W.S. (1987). Syntactic ambiguity and the garden path. ”Quarterly Journal of Experimental Psychology”, 39A, 277-294.

Murray, W.S. and Kennedy, A. (1988). Spatial Coding and the processing of anaphor by good and poor readers: Evidence from eye movement analyses. ”Quarterly Journal of Experimental Psychology”, 40A, 693-718.

Kennedy, A., Murray, W.S., Jennings, F. and Reid, C. (1989). Parsing complements: Comments on the generality of the principle of minimal attachment. ”Language and Cognitive Processes: Special Issue on Parsing and Interpretation”. 4, 51-72.

Spatial coding

The psychological community rapidly established a consensus view that when a reader made an incorrect syntactic attachment (or was induced to do so by some experimental manipulation), this led to the deployment of corrective eye movements, involving looking back at the point in the text where the defective attachment had been made. In 1981, at a Sloan Conference in Amherst, Kennedy pointed out that although this equivalence between re-inspection and syntactic correction seems plausible, it also involves a paradox. This can be illustrated by considering a sentence such as:

”While Mary was mending the old grandfather clock struck twelve”

The words ”old grandfather clock” may initially be attached as the direct object of the verb ”mending”. The missing comma encourages this error. The fact that the attachment is incorrect becomes apparent when the word ”struck” is encountered. The reader needs to re-analyse the sentence and there is ample experimental evidence that this process of re-analysis may be associated with re-inspecting eye movements (sometimes called “regressions”). For example, an eye movement may be made from the word ”struck” back to the word ”mending”.

Consideration of how eye movements in reading are controlled exposes a problem with this account. Visual acuity is restricted, so the question of how the eyes can be selectively and accurately directed to particular words arises. When the target is so visually degraded as to be virtually invisible, how is this achieved? Furthermore, if the target of such reinspections is the point where a faulty attachment was made, does this not imply that the reader was, in some sense, already aware of the potential problem?

Kennedy suggested a possible solution to this paradox: the proposal that readers retain information on the spatial disposition of elements of text. This Spatial Coding Theory has proved controversial with researchers claiming either that no spatial information is maintained or that only very primitive non-specific information is retained.

Kennedy, A. (1983). On looking into space. In K. Rayner (Ed.) ”Eye movements in Reading: Perceptual and Language Processes”. New York: Academic Press.

Kennedy, A. (1982). Eye movements and spatial coding in reading. ”Psychological Research”, 44, 313-322.

Kennedy, A. (1986). The case for place: Text arrangement and reading skill – Invited Tutorial Review. Current Psychological Research and Reviews. 5, 94-104.

Kennedy, A. and Murray, W.S. (1987). Spatial Coding and reading: some comments on Monk (1985). ”Quarterly Journal of Experimental Psychology”, 39A, 649-718.

Murray, W.S. and Kennedy, A. (1988). Spatial Coding and the processing of anaphor by good and poor readers: Evidence from eye movement analyses. ”Quarterly Journal of Experimental Psychology”, 40A, 693-718.

Parafoveal-on-Foveal Effects

In 1995 in a poster presentation at the AmLap Conference in Edinburgh, Kennedy presented evidence that the duration of an eye fixation on a given word could be directly affected by properties (in this case, its frequency of occurrence in the language) of an adjacent word that had not yet been inspected. Up until that time it had been widely accepted that un-fixated words could be pre-processed (the so-called “preview effect”), but any advantage gained from this preview only became evident when the reader actually fixated the next word. The issue was important because of the developing consensus at that time that reading was best characterised as a serial activity in which only one word at a time was attended and all the processing needed to identify that word was completed before the eyes moved on. A preview effect is not inconsistent with this position because the reader’s eyes lag behind the reader’s attention. Attention shifts to the next word while the relevant eye movement is being prepared.

In contrast, evidence that properties of an un-fixated word feed back and directly affect processing time on a currently-fixated word would be seriously damaging to the serial position. Kennedy published the first study demonstrating such “parafoveal-on-foveal” effects in 1998. This was followed by a number of further laboratory studies (most in collaboration with Joël Pynte in Aix-en-Provence) revealing a large number of sources of mutual cross-talk involving adjacent words in text. Factors identified included frequency-of-occurrence, familiarity, the constraint of the initial letters (i.e. how many other words in the language share the same initial letters), and the plausibility of the target sentence-frame.

The initial response from proponents of the strictly serial view of reading to these data was to acknowledge that some mutual interactions between adjacent words might occur, but to claim that the effects were small and fugitive – restricted to the unusual presentation conditions typically found in small-scale experiments (e.g. short sentences on a single line across a computer display). It was claimed that parafoveal-on-foveal interactions were not found in normal reading, and the bulk of evidence at that time supported this contention.

This changed, however, with the publication of an analysis of the Dundee Corpus by Kennedy and Pynte published in 2005. This involved French and English readers working through extended passages of text taken from newspaper articles. Shortly afterwards, Kliegl and colleagues in the University of Potsdam published an even larger analysis of a huge corpus of eye movement data collected during the reading of lengthy passages of text in German. Both the Dundee and Potsdam analyses revealed clear evidence of parafoveal-on-foveal effects. An obvious conclusion is that, rather than characterise the reader’s attention as a “switch” operating in a strictly serial fashion, it seems more plausible that a degree of parallel processing takes place, involving the simultaneous processing of more than one word.

Up to the present, this controversy has not been settled. Although the effects obtained are clearly not an artifact of small-scale laboratory procedures, it must be accepted they are small; it is still possible that artifacts may be involved. One such draws on the fact that eye movement control in normal reading is not particularly precise: sometimes fixations intended for the next word may miss their target. A sufficiently large number of systematic mislocations of this kind might mimic measured parafoveal-on-foveal effects, reducing them to the status of a systematic measurement error. Unfortunately, details of a mechanism that would produce this outcome in practice are lacking. It has also not gone un-noticed that the argument involves a considerable shift of ground, with cross-talk now being seen as characteristic of normal, rather than laboratory, reading. Furthermore, recent evidence that cross-talk varies as a function of the class and syntactic function of the words involved makes an explanation in terms of mislocation implausible.

A critical question in the debate between proponents of serial and parallel views of reading is how the reader arrives relatively effortlessly at a single coherent understanding of the meaning of text. From the serial perspective reading is a sort of “surrogate listening”, in which an orderly pattern of inspection delivers the message in the correct order: the problem is the pattern of inspection is usually anything but orderly. From the parallel perspective the meaning of several words becomes available simultaneously: the problem is how are these competing signals resolved into a single correct meaning?

Kennedy, A. (1995).The influence of parafoveal words on foveal inspection time. AMLaP-95 Conference, Edinburgh, 1995.

Kennedy, A. (1998). The influence of parafoveal words on foveal inspection time: evidence for a processing trade-off. In G. Underwood (Ed.). ”Eye guidance in reading and scene perception” (pp 149 – 223). Oxford: Elsevier.

Kennedy, A. (2000). Parafoveal processing in word recognition. ”Quarterly Journal of Experimental Psychology”, 53A, 429-456.

Kennedy, A., Pynte, J., & Ducrot, S. (2002). Parafoveal-on-foveal interactions in word recognition. ”Quarterly Journal of Experimental Psychology”, 55A, 1307-1337.

Kennedy, A. (2003b). The Dundee Corpus [CD-ROM]. Psychology Department, The University of Dundee.

Kennedy, A., & Pynte, J. (2005). Parafoveal-on-foveal effects in normal reading. ”Vision Research”, 45, 153-168.

Kennedy, A. (2008). Parafoveal-on-foveal effects are not an artifact of mislocated saccades. ”Journal of Eye Movement Research”, 2(1):2, 1-10.

Kliegl, R., Nuthmann, A. & Engbert, R. (2006). Tracking the mind during reading: the influence of past, present and future words on fixation durations. ”Journal of Experimental Psychology: General”,135, 12-35.

Reichle, E. D., Pollatsek, A., Fisher, D. L., & Rayner, K. (1998). Toward a model of eye movement control in reading. ”Psychological Review”, 105, 125-157.

Reichle, E. D., Rayner, K., & Pollatsek, A. (2003). The E-Z Reader model of eye movement control in reading: Comparisons to other models. ”Behavioral and Brain Sciences”, 26, 445-526.

Richter, E. M., Engbert, R., & Kliegl, R. (2006). Current advances in SWIFT. ”Cognitive Systems Research”, 7, 23-33.

Serial Order in reading

Together with colleagues (in particular Joël Pynte in Paris) Kennedy has recently addressed the problem of serial order in reading head on. Proponents of the view that reading is a kind of “surrogate listening” assume that the reader deals with each word in a strict serial order. You either process a word while looking directly at it, or, in certain cases, manage to attend to the next word without ever looking at it directly (in which case the word concerned may be skipped). In both circumstances words are processed, either overtly or covertly, in their correct serial order. Furthermore, this is a necessary order: the phrases “run home” and “home run” mean quite different things and the only way the two meanings can be disambiguated is to ensure they are looked at in the right order.

Notwithstanding the superficial appeal of this position, Kennedy points out that the claim conflicts with the way people actually look at printed text. Real patterns of inspection are relatively chaotic. For example, words are often looked at several times (particularly so for the beginner); the eyes sometimes jump back several words and re-examine segments of text already processed; the reader may return to words that had been skipped; and so on. In fact it has been known for more than twenty years that a strictly serial pattern of word-to-word inspection makes up only a minority of cases, accounting for about twenty percent of all eye fixations. This is obviously an uncomfortable notion for proponents of the metaphor of the reader as listener, but it also poses some severe challenges for all theories of reading. If readers look at words in a haphazard way and process several at the same time, how do they manage to arrive at a single coherent understanding of what they are reading? Why is this chaotic pattern of inspection not reflected in a chaotic jumble of meanings? As some have argued, encoding multiple words simultaneously in reading seems implausible.

Part of the answer may found by noting that printed text is not at all like the auditory stimulus we process when listening. For one thing, it is stable and relatively permanent: unlike speech, it remains out there, available to be re-examined at will. Text is not distributed in time; it is distributed in space, like a picture. When we look at a picture the claim that we encode multiple meanings simultaneously does not seem at all implausible because the visual system is designed to process objects in parallel. To take a concrete example, when we look at a tree, the temporal order of the fixations that fall on it is of no concern at all. It will be seen as a tree whatever the pattern of inspection. In fact there is little or no evidence for what might be termed a canonical scanpath, or “right way of looking”, for a given object. Obviously, particular words convey particular meanings, but the fact that the medium (printed text) is spatially extended means that these meanings can be allocated to specific locations in space. The problem of multiple simultaneous representations disappears once it is accepted that their “simultaneity” is spatial, rather than temporal.

The work of Kennedy on Pynte on non-canonical order in reading has proved controversial and has provoked a vigorous response from proponents of the serial view of reading.

Kennedy, A. and Pynte, J. (2008) The consequences of violations to reading order: An eye movement analysis. ”Vision Research”, 45, 153-168.

Rayner, K., Pollatsek, A., Liversedge, S.P., & Reichle, E.D. Eye movements and non-canonical reading: Comments on Kennedy and Pynte (2008). ”Vision Research”, 49, 2232-2236.

Kennedy, A and Pynte, J. (2009). Non-canonical reading: Reply to Rayner, Pollatsek, Liversedge and Reichle (2008). ”Vision Research”, 49, 2237-2239.

Reichle, E.D., Liversedge, S.P., Pollatsek, A., & Rayner, K. Encoding multiple words simultaneously in reading is implausible. ”Trends in Cognitive Sciences”, 13, 115-119.

Adapted from the Wikipedia article Alan Kennedy (psychologist), under the G. N. U. Free Documentation License. Please also see http://en.wikipedia.org/wiki

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Cross-platform programming is the practice of actively writing software that will work on more than one platform.

Approaches to cross-platform programming

There are different ways of approaching the problem of writing a cross-platform application program. One such approach is simply to create multiple versions of the same program in different ”source trees”—in other words, the Windows version of a program might have one set of source code files and the Macintosh version might have another, while a FOSS *nix system might have another. While this is a straightforward approach to the problem, it has the potential to be considerably more expensive in development cost, development time, or both, especially for the corporate entities. The idea behind this is to create more than two different programs that have the ability to behave similarly to each other. It is also possible that this means of developing a cross-platform application will result in more problems with bug tracking and fixing, because the two different ”source trees” would have different programmers, and thus different defects in each version. The smaller the programming team, the quicker the bug fixes tend to be.

Another approach that is used is to depend on pre-existing software that hides the differences between the platforms—called abstraction of the platform—such that the program itself is unaware of the platform it is running on. It could be said that such programs are ”platform agnostic”. Programs that run on the Java Virtual Machine (JVM) are built in this fashion.

Some applications mix various methods of cross-platform programming to create the final application. An example of this is the Firefox web browser, which uses abstraction to build some of the lower-level components, separate source subtrees for implementing platform-specific features (like the GUI), and the implementation of more than one scripting language to help facilitate ease of portability. Firefox implements XUL, CSS and JavaScript for extending the browser, in addition to classic Netscape-style browser plugins. Much of the browser itself is written in XUL, CSS, and JavaScript, as well.

Cross-platform programming toolkits and environments

There are a number of tools which are available to help facilitate the process of cross-platform programming:

* Cairo: A free software library used to provide a vector graphics-based, device-independent API. It is designed to provide primitives for 2-dimensional drawing across a number of different backends. Cairo is written in C and has bindings for many programming languages.

* FLTK: Another open source cross platform toolkit, but more lightweight because it restricts itself to the GUI.

* fpGUI: An open source widget toolkit that is completely implemented in Object Pascal. It currently supports Linux, Windows and a bit of Windows CE.

* GTK+: An open source widget toolkit for Unix-like systems with X11 and Microsoft Windows.

* Mono (an open source version of Microsoft .NET): A cross-platform framework for applications and programming languages.

* Mozilla: An open source platform for building Mac, Windows and Linux applications.

* OpenGL: A cross-platform 3D graphics library.

* Qt—An application framework and widget toolkit for Unix-like systems with X11, Microsoft Windows, Mac OS X, and other systems—available under both open source and proprietary licenses.

* Simple and Fast Multimedia Library—A multimedia C++ API that provides low and high level access to graphics, input, audio, etc.

* Simple DirectMedia Layer—An open source cross-platform multimedia library written in C that creates an abstraction over various platforms’ graphics, sound, and input APIs. It runs on many operating systems including Linux, Windows and Mac OS X and is aimed at games and multimedia applications.

* Tcl/Tk

* wxWidgets: An open source widget toolkit that is also an application framework. It runs on Unix-like systems with X11, Microsoft Windows and Mac OS X. It permits applications written to use it to run on all of the systems that it supports, if the application does not use any operating system-specific programming in addition to it.

* XVT: A cross-platform toolkit for creating desktop applications in C/C++ on Windows, Linux and Unix (Solaris, HPUX, AIX), and Mac.

* Juce: An application framework written in in C++, used to write native software on numerous systems (Microsoft Windows, POSIX, Mac OS X), with no change to the code.

Adapted from the Wikipedia article Cross-platform, under the G. N. U. Free Documentation License. Please also see http://en.wikipedia.org/wiki

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Lotus Notes can be used for many collaborative applications,including e-mails, calendaring, PIM, instant messaging, Web browsing, and a variety of feature-rich custom applications. It can be used to access both local- and server-based applications and data. The current version of Lotus Notes is 8.5.1. (See http://www-01.ibm.com/software/lotus/products/notes/ for more details).

In early days of the product, the most common applications were threaded discussions and simple contact management databases. Today, Notes also provide blogs, wikis, RSS aggregators, CRM and Help Desk systems, and organizations can build a variety of custom applications for Notes using Domino Designer.

Lotus Notes can be used as an IMAP and POP e-mail client with non-Domino mail servers. Recipient addresses can be retrieved from any LDAP server, including Active Directory. The client also does web browsing, although it can be configured to launch the default browser instead.

Features include group calendaring and scheduling, SMTP/MIME-based e-mail, NNTP-based news support, and automatic HTML conversion of all documents by the Domino HTTP task.

Notes integration with IBM’s Sametime instant messaging allows users to see other users online and chat with one or more of them at the same time. Beginning with Release 6.5 this functionality is built into Notes and presence awareness is available in email and other Notes applications for users in organizations that use both Notes and Sametime.

Since version 7, Notes has provided a web services interface. Domino can be a web server for HTML files too; authentication of access to Domino databases or HTML files uses Domino’s own user directory and external systems such as Microsoft’s Active Directory.

A design client is available to allow rapid development of databases consisting of forms, which allow users to create documents; and views, which display selected document fields in columns.

In addition to being a groupware system (e-mail, calendaring, shared documents and discussions), Notes/Domino is also a platform for developing customized client–server and web applications. Its use of design constructs and code allows easier construction of “workflow”-type applications, which typically have complex approval processes and routing of data.

Since Release 5, Lotus server clustering has been able to provide geographic redundancy for servers.

Later in its product lifecycle, Lotus Notes adopted leading design techniques and prevailing user interface and navigation paradigms first popularized by Microsoft, Apple, Mozilla and others. Features Lotus Notes may have first included were GUI tabs for multiple pages, searches and functions, and squared-off workspace chiclets which are now used on the iPhone.

Lotus 8.5 is the newest release, providing more advancements in building custom software applications.

Client/Server

Lotus Notes and Lotus Domino is a true client/server database environment and the servers themselves can be virtually independent of the hardware and software. The server software is called Lotus Domino and the client software is Lotus Notes. The Domino software can run on Windows, Unix, Linux, AIX, AS/400 and even IBM mainframes such as the iSeries, and can scale to tens of thousands of users per server. There are different supported versions of the Domino server that are supported on the various levels of server operating systems, mostly corresponding to the latest server operating systems only being officially supported by a version of Domino that is released at about the same time as that OS.

Domino has security capabilities on a variety levels. It was actually first designed for a government contract to be used by such agencies and the FBI and CIA, so it would not be a surprise that it has impressive security options available. The authorizations can be very granular, down to the field level in specific records all the way up to 10 different parameters that can be set up at a database level, with intermediate options in between. Users can also assign access for other users to their personal calendar and email on a more generic reader, editor, edit with delete and manage my calendar levels. All of the security in Domino/Notes is independent of the server OS or Active Directory, another flexibility not available with Exchange. Optionally, the Notes client can be configure to have the user can use their Active Directory identity, but after starting the client the standard Notes security protocols are enforced. Any other Active Directory security settings are not applicable other than the user’s password. This was added to the Notes environment to address the standard complaints of having to enter a password for every different system the user might access at work.

Domino servers can support virtually all SMTP standards of mail communications, whitelists, blacklists, encryption, certificates and SSL connections. A Domino server can also be used as an HTTP server and databases can include HTML, XML, cascading style sheets and Java applets to allow for a web interface only limited by the programmer’s abilities to use these tools.

From the client side, a flexibility that can be useful is the ability to easily copy individual records (called documents in Notes) between databases (called Applications in Notes 8.0 and later.) This includes individual memos from a mail file, something that cannot be done from within Exchange/Outlook. Databases/Applications can be designed to handle virtually any kind of data with extremely flexible security parameters including workflow features within the standard Notes client application environment without have write actual code. Dozens of application templates are included at no charge with the software and there are numerous forums and other resources with custom databases available.

Data replication

The first release of Notes included a generalized replication facility. The generalized nature of this feature set it apart from predecessors like Usenet and continues to differentiate Notes from many other systems that now offer some form of synchronization or replication. The facility in Notes and Domino is not limited to email, calendar, and contacts. It works for any data in any application that uses Notes Storage Facility (.nsf) files, which are the standard container for data in the Notes architecture, for its storage. No special programming, tagging, or other configuration is required to enable replication.

Domino servers and Notes clients identify NSF files by their Replica IDs, and keep replicate files synchronized by bidirectionally exchanging data, metadata, and application logic and design. Replication between two servers, or between a client and a server, can occur over a network or a point-to-point modem connection. Replication between servers may occur at intervals according to a defined schedule, in near-real-time when triggered by data changes in server clusters, or when triggered by an administrator or program.

Creation of a local replica of an NSF file on the hard disk of a Notes client enables the user to fully use Notes databases while working off-line; the client synchronizes any changes when client and server next connect. Local replicas are also sometimes maintained for use while connected to the network in order to reduce network latency. Replication between a Notes client and Domino server can run automatically according to a schedule, or manually in response to a user or programmatic request. Since Notes 6, local replicas maintain all security features programmed into the applications. Earlier releases of Notes did not always do so. Early releases also did not offer a way to encrypt NSF files, raising concerns that local replicas might expose too much confidential data on laptops or insecure home office computers. But more recent releases offer encryption, and as of Notes 6 it is the default setting for newly created local replicas.

Security

Notes was the first widely adopted software product to use public key cryptography for client–server and server–server authentication and for encryption of data; it remains the product with the largest installed base of PKI users. Until US laws regulating encryption were changed in 2000, Lotus was prohibited from exporting versions of Notes that supported symmetric encryption keys that were longer than 40 bits. In 1997, Lotus negotiated an agreement with the NSA that allowed export of a version that supported stronger keys with 64 bits, but 24 of the bits were encrypted with a special key and included in the message to provide a “workload reduction factor” for the NSA. This strengthened the protection for users of Notes outside the US against private-sector industrial espionage, but not against spying by the US government. This implementation was widely announced, but with some justification many people did consider it to be a backdoor. Some governments objected to being put at a disadvantage to the NSA, and as a result Lotus continued to support the 40-bit version for export to those countries.

Under current US export laws, Lotus Notes supports only one version of the Notes PKI with 128-bit symmetric keys, 1024-bit public keys, and no workload reduction factor. The Domino server includes security tools support S/MIME, SSL 3.0 with industry standard key sizes for HTTP and other Internet protocols, X.509 client certificates, and an integrated certificate authority.

Notes and Domino also uses a code-signature framework that controls the security context, runtime, and rights of custom code developed and introduced into the environment. Notes 5 introduced execution control lists (ECLs) at the client level. Notes/Domino 6 allowed ECLs to be managed centrally by server administrators through the implementation of Policies. Since release 4.5, the code signatures listed in properly configured ECLs prevent code from being executed by external sources, to avoid virus propagation through Notes/Domino environments. Administrators can centrally control whether each mailbox user can add exceptions to, and thus override, the ECL.

Database security

Every database has an access control list (ACL) that specifies the level of access a user or a server can have to that database. A user’s access level determines what tasks he or she can perform in the database; A server’s access level determines what information the server can replicate. (The names of access levels are the same for users and servers.) Only a user or administrator with Manager access can create or modify the ACL. To set an ACL, the Manager selects the access level, user type, and access level privileges for each user or group in a database. Default entries in the ACL can be set when the Manager creates the database. The manager can also assign roles if the database designer determines this level of access refinement is needed by the application.

Programming

Notes/Domino is a cross-platform, secure, distributed document-oriented database and messaging framework and rapid application development environment that includes pre-built applications like email, calendar, etc. This sets it apart from its major commercial competitors, such as Microsoft Exchange or Novell GroupWise, which are generally purpose-built applications for mail and calendaring that offer APIs for extensibility.

Lotus Domino databases are built using the Domino Designer client, available only for Microsoft Windows; standard user clients are available for Windows, Linux, and Mac OS. A key feature of Notes is that many replicas of the same database can exist at the same time on different servers and clients, across dissimilar platforms; the same storage architecture is used for both client and server replicas. Originally, replication in Notes happened at document (i.e. record) level. With release of Notes 4 in 1996, replication was changed so that it now occurs at field level.

A database is a Notes Storage Facility (.nsf) file, containing basic units of storage known as a “note”. Every note has a UniqueID that is shared by all its replicas. Every replica also has a UniqueID that uniquely identifies it within any cluster of servers, a domain of servers, or even across domains belonging to many organizations that are all hosting replicas of the same database. Each note also stores its creation and modification dates, and one or more Items.

There are several classes of notes, including design notes and document notes. Design notes are created and modified with the Domino Designer client, and represent programmable elements, such as the GUI layout of forms for displaying and editing data, or formulas and scripts for manipulating data. Document notes represent user data, and are created and modified with the Lotus Notes client, via a web browser, via mail routing and delivery, or via programmed code.

Document notes can have parent-child relationships, but Notes should not be considered a hierarchical database in the classic sense of information management systems. Notes databases are also not relational, although there is a SQL driver that can be used with Notes, and it does have some features that can be used to develop applications that mimic relational features. Notes does not support atomic transactions, and its file locking is rudimentary. Notes is a document-oriented database (document-based, schema-less, loosely structured) with support for rich content and powerful indexing facilities. This structure closely mimics paper-based work flows that Notes is typically used to automate.

Items represent the content of a note. Every item has a name, a type, and may have some flags set. A note can have more than one item with the same name. Item types include Number, Number List, Text, Text List, Date-Time, Date-Time List, and Rich Text. Flags are used for managing attributes associated with the item, such as read or write security. Items in design notes represent the programmed elements of a database. For example, the layout of an entry form is stored in the rich text Body item within a form design note. This means that the design of the database can replicate to users’ desktops just like the data itself, making it extremely easy to deploy updated applications.

Items in document notes represent user-entered or computed data. An item named “Form” in a document note can be used to bind a document to a form design note, which directs the Lotus Notes client to merge the content of the document note items with the GUI information and code represented in the given form design note for display and editing purposes. The resulting loose binding of documents to design information is one of the cornerstones of the power of Lotus Notes. Traditional database developers used to working with rigidly enforced schemas, on the other hand, may consider the power of this feature to be a double-edged sword.

Notes applications development uses several programming languages. Formula and LotusScript are the two main ones. LotusScript is similar to, and may even be considered a specialized implementation of, Visual Basic, but with the addition of many powerful native classes that model the Notes environment, whereas Formula is similar to Lotus 1-2-3 formula language but is unique to Notes.

Java was integrated into Lotus Notes beginning with Release 4.5. With Release 5, Java support was greatly enhanced and expanded, and JavaScript was added. LotusScript is the primary tool in developing applications for the Notes client, as well as server-based processing. Java and JavaScript are the primary tools for developing applications for browser access, allowing browsers to emulate the functionality of the Notes client. The Notes client can now natively process Java and JavaScript code, although applications development usually requires at least some code specific to only Notes or only a browser. However, the Mac client does not support Java and the Windows client usually does not support the most recent version of Java.

As of version 6, Lotus established an XML programming interface in addition to the options already available. The Domino XML Language (DXL) provides XML representations of all data and design resources in the Notes model, allowing any XML processing tool to create and modify Notes/Domino data.

Since Release 8.5, XPages were also integrated into Lotus Notes.

External to the Lotus Notes application, IBM provides toolkits in C, C++, and Java to connect to the Domino database and perform a wide variety of tasks. The C toolkit is the most mature, and the C++ toolkit is an objectized version of the C toolkit, lacking many functions the C toolkit provides. The Java toolkit is the least mature of the three and can be used for basic application needs.

Database

Notes includes a database management system but Notes files are different from relational or object databases because they are document-centric. Document-oriented databases such as Notes allow multiple values in items (fields), do not require a schema, come with built-in document-level access control, and store RichText data. Some object-relational features are being developed, and Domino 7 to 8.5.x supports the use of IBM’s DB2 database as an alternative store for Notes databases. (According to IBM, this NSFDB2 feature, however, is now in [http://www-01.ibm.com/support/docview.wss?uid=swg21384421 maintenance mode with no further development planned.]) A Notes database can be mapped to a relational database using tools like DECS, [LEI], JDBCSql for Domino or NotesSQL.

It could be argued that Notes is a multi-value database system like PICK, or that it is an object system like Zope, but it is in fact unique. Whereas the temptation for relational database programmers is to normalize databases, Notes databases must be denormalized. RDBMS developers often find it difficult to conceptualize the difference. It may be useful to think of a Notes document (a ‘note’) as analogous to an XML document natively stored in a database (although with limitations on the data types and structures available).

The benefits of this data structure are:

# No need to define size of fields, or datatype;

# Attributes (Notes fields) that are null take up no space in a database;

# Built-in full text searching.

Adapted from the Wikipedia article IBM Lotus Notes, under the G. N. U. Free Documentation License. Please also see http://en.wikipedia.org/wiki

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The first incarnation of what was later to be the APL programming language was published and formalized in ”A Programming Language”, a book describing a notation invented in 1957 by Kenneth E. Iverson while at Harvard University. Iverson had developed a mathematical notation for manipulating arrays that he taught to his students.

In 1960, he began work for IBM and working with Adin Falkoff, created APL based on the notation he had developed. This notation was used inside IBM for short research reports on computer systems, such as the Burroughs B5000 and its stack mechanism when stack machines versus register machines were being evaluated by IBM for upcoming computers.

Also in 1960, Iverson was already also using his notation in a draft copy of Chapter 6 called “A programming language” for the book he was writing with Fred Brooks, ”Automatic Data Processing”, which would later be published in 1963.

Published in 1962, the notation described in ”A Programming Language” was recognizable yet distinct from later APL.

As early as 1962, the first attempt to use the notation to describe a complete computer system happened after Falkoff discussed with Dr. William C. Carter his work in the standardization of the instruction set for the machines that later became the IBM System/360 family.

In 1963, Dr. Herbert Hellerman, working at the IBM Systems Research Institute, implemented a part of the notation on an IBM 1620 computer, and it was used by students in a special high school course on elementary functions. This implementation of a portion of the notation was called PAT (Personalized Array Translator).

In 1963, Falkoff, Iverson, and Edward H. Sussenguth Jr., all working at IBM, used the notation for a formal description of the IBM System/360 series machine architecture and functionality which resulted in a paper published in IBM Systems Journal in 1964. After this was published, the team turned their attention to an implementation of the notation on a computer system. One of the motivations for this focus of implementation was the interest of John L. Lawrence who had new duties with Science Research Associates, an educational company bought by IBM in 1964. Lawrence asked Iverson and his group to help utilize the language as a tool for the development and use of computers in education.

After Lawrence M. Breed and Philip S. Abrams of Stanford University joined the team at IBM Research, they continued their prior work on an implementation programmed in FORTRAN IV for a portion of the notation was done for the IBM 7090 computer running under the IBSYS operating system. This work was finished in late 1965 and later known as IVSYS (Iverson System). The basis of this implementation was described in detail by Abrams in a Stanford University Technical Report, “An Interpreter for Iverson Notation” in 1966. Like Hellerman’s PAT system earlier, this implementation did not include the APL character set but used special English reserved words for functions and operators. The system was later adapted for a time-sharing system and, by November 1966, it had been reprogrammed for the IBM/360 Model 50 computer running in a time sharing mode and was used internally at IBM.

A key development in the ability to use APL effectively, before the widespread use of CRT terminals, was the development of a special IBM Selectric typewriter interchangeable typeball with all the special APL characters on it. This was used on paper printing terminal workstations using the Selectric typewriter and typeball mechanism, such as the IBM 1050 and IBM 2741 terminal. Keycaps could be placed over the normal keys to show which APL characters would be entered and typed when that key was struck. This meant that, for the first time, a programmer could actually type in and see real APL characters as used in Iverson’s original notation and not be forced to use awkward English keyword representations of them. Falkoff and Iverson had the special APL Selectric typeballs, 987 and 988, designed in late 1964, although no APL computer system was available to use them. Iverson cited Falkoff as the inspiration for the idea of using an IBM Selectric typeball for the APL character set.

The IBM 2741 keyboard layout with the APL typeball print head inserted looked this way to the programmer:

:

Some APL symbols, even with the APL characters on the typeball, still had to be typed in by over-striking two existing typeball characters. An example would be the “grade up” character which had to be made from a “delta” (shift-H) and a “Sheffer stroke” (shift-M). This was necessary because the APL character set was larger than the 88 characters allowed on the Selectric typeball.

The first APL interactive login and creation of an APL workspace was in 1966 by Larry Breed using a 1050 terminal at the IBM Mohansic Labs near Thomas J. Watson Research Center, the home of APL, in Yorktown Heights, New York.

IBM was chiefly responsible for the introduction of APL to the marketplace.

APL was first available in 1967 for the IBM 1130 as ”APL1130”. It would run in as little as 8k 16 bit words of memory, and used a dedicated 1 megabyte hard disk.

APL gained its foothold on mainframe timesharing systems from the late 1960s through the 1980s. Additional improvements in performance for mainframe systems included the “APL Assist Microcode” in which some support for APL execution was included in the actual hardware as opposed to APL being exclusively a software product. Later, when suitably performing hardware was finally available starting in the early to mid-1980s, many users migrated their applications to the personal computer environment.

Early IBM APL interpreters for IBM 360 and IBM 370 hardware implemented their own multi-user management instead of relying on the host services, thus they were timesharing systems in their own right. First introduced in 1966, the ”APL360”

system was a multi-user interpreter. The ability to programmatically communicate with the operating system for information and setting interpreter system variables was done through an invention called “I-beam” functions, using both monadic and dyadic operations.

In 1973, IBM released ”APL.SV” which was a continuation of the same product, but which offered shared variables as a means to access facilities outside of the APL system, such as operating system files. In the mid 1970s, the IBM mainframe interpreter was even adapted for use on the IBM 5100 desktop computer, which had a small CRT and an APL keyboard, when most other small computers of the time only offered BASIC. In the 1980s, the ”VSAPL” program product enjoyed widespread usage with CMS, TSO, VSPC, MUSIC/SP and CICS users.

In 1973-1974, Dr. Patrick Haggerty introduced the APL interpreter on Sperry Corporation computers. Dr. Haggerty, single-handedly wrote the University of Maryland APL processor for the Sperry Univac 1100 Series mainframe computers. At the time, Sperry had nothing. In 1974, student Alan Stebbens was assigned the task of implementing an internal function. And student Bill Linton caused massive dumps to occur as he practiced developing APL programs in the third-floor TTY room, causing Dr. Haggerty to burst through the TTY door to halt the practice until Dr. Haggerty fixed the APL interpreter bug.

Several timesharing firms sprang up in the 1960s and 1970s which sold APL services using modified versions of the IBM APL360 interpreter. In North America, the better-known ones were I. P. Sharp Associates, Scientific Time Sharing Corporation, and The Computer Company (TCC). With the advent first of less expensive mainframes such as the IBM 4331 and later the personal computer, the timesharing industry had all but disappeared by the mid 1980s.

”Sharp APL” was available from I. P. Sharp Associates, first on a timesharing basis in the 1960s, and later as a program product starting around 1979. ”Sharp APL” was an advanced APL implementation with many language extensions, such as ”packages” (the ability to put one or more objects into a single variable), file system, nested arrays, and shared variables.

APL interpreters were available from other mainframe and mini-computer manufacturers as well, notably Burroughs, CDC, Data General, DEC, Harris, Hewlett-Packard, Siemens, Xerox, and others.

In 1979, Iverson received the Turing Award for his work on APL.

APL2

Starting in the early 1980s, IBM APL development, under the leadership of Dr Jim Brown, implemented a new version of the APL language which contained as its primary enhancement the concept of ”nested arrays”, where an array can contain other arrays, as well as new language features which facilitated the integration of nested arrays into program workflow. Ken Iverson, no longer in control of the development of the APL language, left IBM and joined I. P. Sharp Associates, where one of his major contributions was directing the evolution of Sharp APL to be more in accordance with his vision.

As other vendors were busy developing APL interpreters for new hardware, notably Unix-based microcomputers, APL2 was almost always the standard chosen for new APL interpreter developments. Even today, most APL vendors cite APL2 compatibility, which only approaches 100%, as a selling point for their products.

”APL2” for IBM mainframe computers is still available today, and was first available for CMS and TSO in 1984. The APL2 Workstation edition (Windows, OS/2, AIX, Linux, and Solaris) followed much later in the early 1990s.

Microcomputers

The first microcomputer implementation of APL was on the 8008-based MCM/70, the first general purpose personal computer, in 1973.

The VideoBrain Family Computer, released in 1977, only had one programming language available for it and that was a dialect of APL called APL/S.

A Small APL for the Intel 8080 called EMPL was released in 1977, and Softronics APL, with most of the functions of full APL, for 8080-based CP/M systems was released in 1979.

In 1977, the Canadian firm Telecompute Integrated Systems, Inc. released a business-oriented APL interpreter known as TIS APL, for Z80-based systems. It featured the full set of file functions for APL, plus a full screen input and switching of right and left arguments for most dyadic operators by introducing ~. prefix to all single character dyadic functions such as – or /.

Vanguard APL was available for Z80 CP/M-based processors in the late 1970s. TCC released APL.68000 in the early 1980s for Motorola 68000-based processors, this system being the basis for MicroAPL Limited’s APLX product. I. P. Sharp Associates released a version of their APL interpreter for the IBM PC and PC/370 – for the IBM PC, an emulator was written which facilitated reusing much of the IBM 370 mainframe code. Arguably, the best known APL interpreter for the IBM Personal Computer was STSC’s APL*Plus/PC.

The Commodore SuperPET, introduced in 1981, included an APL interpreter developed by the University of Waterloo.

In the early 1980s, the Analogic Corporation developed ”The APL Machine”, which was an array processing computer designed to be programmed only in APL. There were actually three processing units, the user’s workstation, an IBM PC, where programs were entered and edited, a Motorola 6800 processor which ran the APL interpreter, and the Analogic array processor which executed the primitives. At the time of its introduction The APL Machine was likely the fastest APL system available. Although a technological success, The APL Machine was a marketing failure. The initial version supported a single process at a time. At the time the project was discontinued, the design had been completed to allow multiple users. As an aside, an unusual aspect of The APL Machine was that the library of workspaces was organized such that a single function or variable which was shared by many workspaces existed only once in the library. Several of the members of The APL Machine project had previously spent a number of years with Burroughs implementing ”APL700”.

At one stage, Microsoft Corporation planned to release a version of APL, but these plans never materialized.

An early 1978 publication of Rodnay Zaks from Sybex was ”A microprogrammed APL implementation” ISBN 0895880059 which is the complete, total source listing for the microcode for a PDP / LSI-11 processor implementing APL. This may have been the substance of his PhD thesis.

Extensions

Recent extensions to APL include:

* Object-oriented programming

* Support for .Net, ActiveX, operating system resources & connectivity

* APL as a native .NET language using Visual Studio 2008

* Integrated charting and manipulation of SQL databases

* XML-array conversion primitives

* [http://foldoc.org/lambda+expression Lambda expressions]

Adapted from the Wikipedia article APL (programming language), under the G. N. U. Free Documentation License. Please also see http://en.wikipedia.org/wiki

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