How to change argv[0] value in shell / bash script?

Question

The set command can be used to change values of the positional arguments $1 $2 ...

But, is there any way to change $0 ?

Answer 1

Here is another method. It is implemented through direct commands execution which is somewhat better than sourcing (the dot command). But, this method works only for shell interpreter, not bash, since sh supports -s -c options passed together:

#! /bin/sh
# try executing this script with several arguments to see the effect

test ".$INNERCALL" = .YES || {
    export INNERCALL=YES
    cat "$0" | /bin/sh -s -c : argv0new "$@"
    exit $?
}

printf "argv[0]=$0\n"
i=1 ; for arg in "$@" ; do printf "argv[$i]=$arg\n" ; i=`expr $i + 1` ; done

The expected output of the both examples in case ./the_example.sh 1 2 3 should be:

argv[0]=argv0new
argv[1]=1
argv[2]=2
argv[3]=3