UNIX for Dummies Questions & Answers

Store the output of whoami in the variable user.

Store the script name in DZERO (this is unreliable).

Extract the filename from $DZERO and store it in PROG. The more efficient method is:

Code:

PROG=${DZERO##*/}

If the file in $DZERO is a symbolic link, find the file to which it is linked. (Not the best way to do that.)

Store the directory containing the command in PDIR. The more efficient method is:

Code:

case $DZERO in
   *.*) PDIR=${DZERO%/*} ;;
   *) PDIR=. ;;
esac

A very inefficient way of doing:

Code:

case $PDIR in
   .) PDIR=$PWD ;;
   /*) PDIR=$PWD/$PDIR ;;
esac

That is, getting the full path to the script's directory into PDIR.

The script is trying to do something that cannot be done reliably, and that is usually tring to solve the wrong problem. It is doing it badly, both in terms of the methods used and the code that implements those methods.