Advanced Bash-Scripting Guide

They are not the same $0 $1 $2 variables as your own shell. They are in single quotes:

Code:

'echo "Dumping file: $2" >> "$1"; w3m "$2" >> "$1" 2>&1'

...so they are passed into sh -c unparsed, for it to handle.

I have my doubts about them too. Nowhere, I think. There is a different form of shell code which I think they tried to adapt from:

Code:

echo 'echo arg1 $1 arg2 $2 arg3 $3 arg4 $4' | sh -s -- a b c d

This runs with the result:

Code:

arg1 a arg2 b arg3 c arg4 d

...But it runs code from standard input, not -c, so can't be used with xargs.

Someone tried to adapt that into a form suitable for xargs and didn't know what those arguments were for, so left them dangling.