Flags. Flags are a way to set options and pass in arguments to the commands you run. … You should read the documentation of each command to know what flags are available. For example, running ls with the -l flag ( ls -l ) will include more information in the result and change the format of what is returned.

What is Flag in command?

Flags modify the operation of a command and are sometimes called options. A flag is set off by spaces or tabs and usually starts with a dash (-). Exceptions are ps, tar, and ar, which do not require a dash in front of some of the flags. For example, in the following command: ls -a -F.

What is Flag in shell script?

Getting arguments using getopts

You can read more about getopts here. flag is the iterator variable here. In bash the do followed by while statement specifies starting of block which contains satement to be executed by while . The ending of block is specified by done .