|
|
bash Quick Reference
The original Bourne shell distributed with V7 Unix in 1979 became the standard shell for writing shell scripts. The Bourne shell is still be found in /bin/sh on many commercial Unix systems. The Bourne shell itself has not changed that much since its initial release, although it has seen modest enhancements over the years. The most notable new features were the CDPATH variable and a built-in test command with System III (circa 1980), command hashing and shell functions for System V Release 2 (circa 1984), and the addition of job control features for System V Release 4 (1989).
Because the Berkeley C shell (csh) offered features that were more pleasant for interactive use, such as command history and job control, for a long time the standard practice in the Unix world was to use the Bourne shell for programming and the C shell for daily use. David Korn at Bell Labs was the first developer to enhance the Bourne shell by adding csh-like features to it: history, job control, and additional programmability. Eventually, the Korn shell’s feature set surpassed both the Bourne shell and the C shell, while remaining compatible with the Bourne shell for shell programming. Today, the POSIX standard defines the “standard shell” language and behavior based on the System V Bourne shell, with a selected subset of features from the Korn shell.
The Free Software Foundation, in keeping with its goal to produce a complete Unix workalike system, developed a clone of the Bourne shell, written from scratch, named “Bash,” the Bourne-Again SHell. Over time, Bash has become a POSIX-compliant version of the shell, with many additional features. A large part of these additional features overlap the features of the Korn shell, but Bash is not an exact Korn shell clone.
Download Link
All rights reserved. All other trademarks appearing on on this site are the property of their respective owners. We don't store any files on this server, we just index the link from the other website.
|
|
|
|
