Shell equality operators (=, ==, -eq) Asked 12 years, 1 month ago Modified 3 years, 7 months ago Viewed 651k times

Jul 22, 2018 · In shell scripts, what is the difference between $@ and $*? Which one is the preferred way to get the script arguments? Are there differences between the different shell …

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.

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 …

$(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 …

I often come across $?, $0, $1, $2, etc in shell scripting. I know that $? returns the exit status of the last command: echo "this will return 0" echo $? But what do the others do? …

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

Nov 29, 2025 · The shell is the program which actually processes commands and returns output. Most shells also manage foreground and background processes, command history and …

Oct 27, 2021 · The shell will try to create directory test and then, only if it was successful will try create file inside it. So you may interrupt a sequence of steps if one of them failed.

it seems < is for passing file (or directory), << @ for passing multiple lines (similar to the banner command in cisco switches; as terminated by a custom string @ in this case), and <<< to pass …