Shell equality operators (=, ==, -eq) Asked 12 years, 2 months ago Modified 3 years, 9 months ago Viewed 655k times

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

$(command) is “command substitution”. As you seem to understand, it runs the command, captures its output, and inserts that into the command line that contains the $(…); e.g., $ ls -ld $(date +%B).txt …

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.

Sep 14, 2012 · $! is the PID of the most recent background command. $0 is the name of the shell or shell script. Most of the above can be found under Special Parameters in the Bash Reference …

What does $# mean in shell? I have code such as if [ $# -eq 0 ] then I want to understand what $# means, but Google search is very bad for searching these kinds of things.

Feb 20, 2011 · When going through one shell script, I saw the term "$?". What is the significance of this term?

Aug 1, 2019 · What does echo $? mean in shell programming? true echo $? # echoes 0 false echo $? # echoes 1 From the manual: (acessible by calling man bash in your shell) ? Expands to the exit status …

May 8, 2012 · I understand the basic difference between an interactive shell and a non-interactive shell. But what exactly differentiates a login shell from a non-login shell? Can you give examples for uses of...

Sep 17, 2012 · Meaning of "=~" operator in shell script [duplicate] Ask Question Asked 13 years, 5 months ago Modified 12 years, 7 months ago