0x000d0000 (ˆÏÎÍÌËl–äY>” ªa,j÷ßPA¸n4%1hßÇ ƒt‹ÆÅÉ  BASH - The Bourne-Again Shell Bash is the shell, or command language interpreter, that will appear in the GNU operating system. Bash is an sh-compatible shell that incorporates useful features from the Korn shell (ksh) and C shell (csh). It is intended to conform to the IEEE POSIX P1003.2/ISO 9945.2 Shell and Tools standard. It offers functional improvements over sh for both programming and interactive use. In addition, most sh scripts can be run by Bash without modification. Bash is quite portable. It uses a configuration system that discovers characteristics of the compilation platform at build time, and may therefore be built on nearly every version of UNIX. Ports to UNIX-like systems such as QNX and Minix and to non-UNIX systems such as OS/2, Windows 95, and Windows NT are available. Bash includes the following features: Editing and Completion Bash offers a command-line editing facility which permits users to edit command lines using familiar emacs or vi-style editing commands. Editing allows corrections to be made without having to erase back to the point of error or start the command line anew. The editing facilities include a feature that allows users to complete command and file names. The Bash line editing library is fully customizable. Users may define their own key bindings -- the action taken when a key is pressed. A number of variables to fine-tune editing behavior are also available. History and Command Re-entry The Bash history feature remembers commands entered to the shell and allows them to be recalled and re-executed. The history list may be of unlimited size. Bash allows users to search for previous commands and reuse portions of those commands when composing new ones. The history list may be saved across shell sessions. Bash allows users to control which commands are saved on the history list. Job Control On systems that support it, Bash provides an interface to the operating system's job control facilities, which allow processes to be suspended and restarted, and moved between the foreground and background. Bash allows users to selectively `forget' about background jobs. Shell Functions and Aliases These mechanisms are available to bind a user-selected identifier to a list of commands that will be executed when the identifier is used as a command name. Functions allow local variables and recursion, and have access to the environment of the calling shell. Aliases may be used to create a mnemonic for a command name, expand a single word to a complex command, or ensure that a command is called with a basic set of options. Arrays Bash-2.0 supports indexed arrays of unlimited size. The subscript for an array is an arithmetic expression. Arrays may be assigned to with a new compound assignment syntax, and several builtins have options to operate on array variables. Bash includes a number of built-in array variables. Arithmetic Bash allows users to perform integer arithmetic in any base from two to sixty-four. Nearly all of the C language arithmetic operators are available with the same syntax and precedence as in C. Arithmetic expansion allows an arithmetic expression to be evaluated and the result substituted into the command line. Shell variables can be used as operands, and the value of an expression may be assigned to a variable. An arithmetic expression may be used as a command; the exit status of the command is the value of the expression. ANSI-C Quoting There is a new quoting syntax that allows backslash-escaped characters in strings to be expanded according to the ANSI C standard. Tilde Expansion Users' home directories may be expanded using this feature. Words beginning with a tilde may also be expanded to the current or previous working directory. Brace Expansion Brace expansion is a convenient way to generate a list of strings that share a common prefix or suffix. Substring Capabilities Bash allows new strings to be created by removing leading or trailing substring