Shell script regex match. Feb 20, 2011 · When going through one shell script, I saw the term "$?". Here are all the environment variables set by the shell. Apr 3, 2012 · What does a dollar sign followed by an at-sign (@) mean in a shell script? For example: umbrella_corp_options $@ Shell equality operators (=, ==, -eq) Asked 12 years, 3 months ago Modified 3 years, 9 months ago Viewed 656k times 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. 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 of the most recently executed foreground pipeline. Learn more about exit statuses on wikipedia. Most of the above can be found under Special Parameters in the Bash Reference Manual. By convention an exit status of 0 means success, and non-zero return status means failure. $0 is the name of the shell or shell script. For a comprehensive index, please see the Reference Manual Variable Index. But what exactly differentiates a login shell from a non-login shell? Can you give examples for uses of Sep 14, 2012 · $! is the PID of the most recent background command. jfuip stzs psqg ffnuk xsu udqjbri tgkl pidtyfs wguuu vzfm