Unix Variable $* and $# Difference

Script

#!/bin/bash

echo “Using \”\$*\”:”
for a in “$*”; do
echo $a;
done

echo -e “\nUsing \$*:”
for a in $*; do
echo $a;
done

echo -e “\nUsing \”\$@\”:”
for a in “$@”; do
echo $a;
done

echo -e “\nUsing \$@:”
for a in $@; do
echo $a;
done

Run

variabledif.sh one two “three four”

The explanation and the results for the four cases are below.

In the first case, the parameters are regarded as one long quoted string:

Using “$*”:
one two three four

Case 2 (unquoted) – the string is broken into words by the for loop:

Using $*:
one
two
three
four

Case 3 – it treats each element of $@ as a quoted string:

Using "$@":
one
two
three four

The last case – it treats each element as an unquoted string, so the last one is again split by what amounts to for three four:

Using $@:
one
two
three
four