I'm trying to learn shell scripting, and I need to understand someone else's code. What is the $? variable hold? I can't Google search the answer because they block punctuation characters.

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 …

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 …

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

Oct 27, 2021 · What is the purpose of "&&" in a shell command? Asked 14 years, 10 months ago Modified 2 years, 5 months ago Viewed 683k times

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 …

Nov 15, 2010 · A bashism is a shell feature which is only supported in bash and certain other more advanced shells. It will not work under busybox sh or dash (which is /bin/sh on a lot of …

In man bash we can read in Shell Builtin Commands section (online doc): Unless otherwise noted, each builtin command documented in this section as accepting options preceded by - accepts …

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I am building a shell as part of a school assignment, a limited version of bash. The whole program seems to function alright without any kind on leaks, but when I send invalid/nonexistent …