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?

What can you do with the eval command? Why is it useful? Is it some kind of a built-in function in bash? There is no man page for it..

In terminal, how can I define a key to go to the previous directory which I was in when changing directory with the cd command? For example, I'm in /opt/soft/bin and I cd into /etc/squid3 and I …

Aug 17, 2012 · In bash all I know is that rmdir directoryname will remove the directory but only if it's empty. Is there a way to force remove subdirectories?

What is the Linux command to check the server OS and its version? I am connected to the server using shell.

Aug 24, 2011 · I have a directory that is unpacked, but is in a folder. How can I move the contents up one level? I am accessing CentOS via SSH.

It's probably the most common command to use in an if, which can lead to the assumption that it's part of the shell's syntax. But if you want to test whether a command succeeded or not, use …

More precisely, a double dash (--) is used in most Bash built-in commands and many other commands to signify the end of command options, after which only positional ("non-option") …

Shell scripting: -z and -n options with if Ask Question Asked 11 years, 5 months ago Modified 4 months ago