bash - What are the special dollar sign shell variables ... - Stack ...
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 …
How do AND and OR operators work in Bash? - Stack Overflow
How do AND and OR operators work in Bash? Asked 12 years, 11 months ago Modified 2 years, 8 months ago Viewed 22k times
What does 'set -e' mean in a Bash script? - Stack Overflow
By default, Bash does not do this. This default behavior is exactly what you want if you are using Bash on the command line you don't want a typo to log you out! But in a script, you really want the …
bash - Shell equality operators (=, ==, -eq) - Stack Overflow
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 …
bash - What is the purpose of "&&" in a shell command? - Stack …
Oct 27, 2021 · $ command one && command two the intent is to execute the command that follows the && only if the first command is successful. This is idiomatic of Posix shells, and not only found in …
shell - Bash regex =~ operator - Stack Overflow
Oct 18, 2013 · What is the operator =~ called? I'm not sure it has a name. The bash documentation just calls it the =~ operator. Is it only used to compare the right side against the left side? The right side is …
Meaning of $? (dollar question mark) in shell scripts
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 …
linux - What does $@ mean in a shell script? - Stack Overflow
Apr 3, 2012 · What does a dollar sign followed by an at-sign (@) mean in a shell script? For example: umbrella_corp_options $@
What's the meaning of the parameter -e for bash shell command line?
123 I have as bash shell script with header #!/bin/bash -e. When I run the script, it will be interrupted after the grep command runs, but when I remove the parameter -e, then the script can be run …
An "and" operator for an "if" statement in Bash - Stack Overflow
Modern shells such as Bash and Zsh have inherited this construct from Ksh, but it is not part of the POSIX specification. If you're in an environment where you have to be strictly POSIX compliant, stay …