Sep 14, 2012 · In Bash, there appear to be several variables which hold special, consistently-meaning values. For instance, ./myprogram &; echo $! will return the PID of the process which …

Jul 25, 2017 · Furthermore, when you use bash -c, behavior is different than if you run an executable shell script, because in the latter case the argument with index 0 is the shell command used to invoke it.

If not quoted, it is a pattern match! (From the Bash man page: "Any part of the pattern may be quoted to force it to be matched as a string."). Here in Bash, the two statements yielding "yes" are pattern …

Oct 27, 2021 · Furthermore, you also have || which is the logical or, and also ; which is just a separator which doesn't care what happend to the command before.

All the bash command line switches are documented in man bash. -e Exit immediately if a pipeline (which may consist of a single simple command), a subshell command enclosed in parentheses, or …

Use -e . For single ' [', the bash builtin behaves the same as the test bash builtin, which behaves the same as /usr/bin/[ and /usr/bin/test (the one is a symlink to the other). Note the effect of -a depends …

Apr 3, 2012 · What does a dollar sign followed by an at-sign (@) mean in a shell script? For example: umbrella_corp_options $@

bash shell scripting control-flow Improve this question edited Nov 16, 2011 at 22:16 Gilles 'SO- stop being evil'

Make sure you have the #!/bin/bash shebang line for your script if you use double brackets. See also Bash FAQ - "What is the difference between test, [ and [ [ ?" Bash Practices - Bash Tests Server …

Feb 10, 2010 · Bash always seemed backward with numeric evaluations using an operator consisting of a string (-eq) and string comparisons using a numeric operator "==" or "=" just you mess you up. If …