shell variable การใช้

• Shell variables can be either simple strings or arrays of strings.
• Shell variables, created using the set or @ statements, are internal to C shell.
• If the first word of the savehist shell variable is set to a number, at most that many lines are saved.
• It added shell variables ( precursors of environment variables, including the search path mechanism that evolved into $ PATH ), user-executable shell scripts, and interrupt-handling.
• Some of the shell variables are predefined and used to control various internal C shell options, e . g ., what should happen if a wildcard fails to match anything.
• I use'tcsh'out of familiarity-it lets you do math on shell variables using the'@'command-there is bound to be a way to do it with bash also:
• :: ( where that thing between the single quotes is a single ESC character ), and then use it all over the place ( remembering to use double quotes, so that the shell variable is expanded ):