Environment variable

Environment variables are a set of dynamic named values that can affect the way running processes will behave on a computer.

They are part of the environment in which a process runs. For example, a running process can query the value of the TEMP environment variable to discover a suitable location to store temporary files, or the HOME or USERPROFILE variable to find the directory structure owned by the user running the process.

They were introduced in their modern form in 1979 with Version 7 Unix, so are included in all Unix operating system flavors and variants from that point onward including Linux and OS X. From PC DOS 2.0 in 1982, all succeeding Microsoft operating systems including Microsoft Windows, and OS/2 also have included them as a feature, although with somewhat different syntax, usage and standard variable names.

Details

In all Unix and Unix-like systems, each process has its own separate set of environment variables. By default, when a process is created, it inherits a duplicate environment of its parent process, except for explicit changes made by the parent when it creates the child. At the API level, these changes must be done between running fork and exec. Alternatively, from command shells such as bash, a user can change environment variables for a particular command invocation by indirectly invoking it via env or using the ENVIRONMENT_VARIABLE=VALUE <command> notation. All Unix operating system flavors, DOS, and Windows have environment variables; however, they do not all use the same variable names. A running program can access the values of environment variables for configuration purposes.

CLS (command)

In computing, CLS (for clear screen) is a command used by the command line interpreters COMMAND.COM and CMD.EXE on DOS, OS/2 and Microsoft Windows operating systems to clear the screen or console window of commands and any output generated by them. It does not clear the user's history of commands, however. The command is also available in the DEC RT-11 operating system. In other environments, such as Linux and Unix, the same functionality is provided by the clear command.

While the ultimate origins of using the three-character string CLS as the command to clear the screen likely predate Microsoft's use, this command was present before its MS-DOS usage, in the embedded ROM BASIC dialects Microsoft wrote for early 8-bit microcomputers (such as TRS-80 Color BASIC), where it served the same purpose. The MS-DOS dialects of BASIC written by Microsoft, BASICA and GW-BASIC, also have the CLS command as a BASIC keyword - as do various non-Microsoft implementations of BASIC such as BBC BASIC found on the BBC Micro computers. The CLS command is also present in BASIC versions for Microsoft Windows, however this generally clears text printed on the form, rather than the whole screen or controls on the form.

CONFIG.SYS

CONFIG.SYS is the primary configuration file for the DOS and OS/2 operating systems. It is a special ASCII text file that contains user-accessible setup or configuration directives evaluated by the operating system during boot. CONFIG.SYS was introduced with DOS 2.0.

Usage

The directives in this file configure DOS for use with devices and applications in the system. The CONFIG.SYS directives also set up the memory managers in the system. After processing the CONFIG.SYS file, DOS proceeds to load and execute the command shell specified in the SHELL line of CONFIG.SYS, or COMMAND.COM if there is no such line. The command shell in turn is responsible for processing the AUTOEXEC.BAT file.

CONFIG.SYS is composed mostly of name=value directives which look like variable assignments. In fact, these will either define some tunable parameters often resulting in reservation of memory, or load files, mostly device drivers and TSRs, into memory.

In DOS, CONFIG.SYS is located in the root directory of the drive from which the system was booted.

Departure

Departure or Departures may refer to:

Film and television

Publishing

Aviation

In Search of the Lost Chord

In Search of the Lost Chord is the third album by The Moody Blues, released in 1968 through Deram Records.

Content and style

In Search of the Lost Chord is a concept album around a broad theme of quest and discovery, including world exploration ("Dr. Livingstone, I Presume"), music and philosophy through the ages ("House of Four Doors"), lost love ("The Actor"), spiritual development ("Voices in the Sky"), knowledge in a changing world ("Ride My See-Saw"), higher consciousness ("Legend of a Mind"), imagination ("The Best Way to Travel"), and space exploration ("Departure"). Space exploration would go on to become the theme of the Moodies' 1969 album To Our Children's Children's Children, inspired by and dedicated to the Apollo 11 mission. The mysterious "lost chord" of the title is revealed to be the mantra "Om" (in the last stanza of Graeme Edge's poem "The Word").

According to keyboardist Mike Pinder, the title was inspired by Jimmy Durante's humorous song, "I'm the Guy that Found the Lost Chord," itself a reference to The Lost Chord by Sir Arthur Sullivan.

Departure (Jesse McCartney album)

Departure is the third studio album by American recording artist Jesse McCartney. It was released on May 20, 2008 through Hollywood Records. The album was re-released on April 7, 2009, under the name Departure: Recharged. The album featured a heavier R&B sound, and spawned three US Hot 100 top 40 hits, "Leavin'", "How Do You Sleep?", and "Body Language". The latter two were released as singles from the recharged edition.

Album information

It has been described by McCartney as a complete change in musical style compared to his previous releases. About the new album, he said, "I'm shooting for Prince chord changes, Michael [Jackson] melodies, and the bigness of Madonna - fun '80s stuff. That's the best that I can put it". Producers on the album include Tricky Stewart, The-Dream, Sean Garrett, The Clutch, Brian Kennedy, and J. R. Rotem.

The album leaked April 30, 2008, almost three weeks before the release date. Departure was released one week early on the Canadian iTunes Store. The CD was released using CDVU+ technology. Some countries, including the UK and Brazil, were excluded from the recycled packaging and CDVU+ Software on the release.