Department of Engineering

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Arguments from the command line

It is easy to write a script that takes arguments (options) from the command line. Type this script into a file called args.

echo this $0 command has $# arguments.
echo They are $*

The echo command echoes the rest of the line to the screen by default. Within a shell script, $0 denotes the script's name, $1 denotes the first argument mentioned on the command line and so on. Make the script executable then try it out with various arguments. For example, if you type

    args first another

then

• $# would be replaced by 2, the number of arguments,

• $0 would be substituted by args,
• $* would be substituted by first another, (`*' having a wildcard meaning)