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?

Shell equality operators (=, ==, -eq) Asked 12 years ago Modified 3 years, 6 months ago Viewed 649k times

Shell - "Shell" is a program, which facilitates the interaction between the user and the operating system (kernel). There are many shell implementations available, like sh, Bash, C shell, Z …

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 …

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? …

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 …

Dec 22, 2010 · 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.

docker debug <container or image> It allows you to get a shell (bash/fish/zsh) into any container. It also works for stopped containers and images. Essentially it's a replacement of docker exec …

Jul 14, 2011 · The Bash shell supports two ways to do arithmetic operation, one defined by the built-in let command and the other the $((..)) operator. The former evaluates an arithmetic …