#!/bin/sh

AWK="/usr/bin/awk"

if [[ "$1" == "" ]]; then
  base=`basename $0`
  echo "Usage: $base unixuser"
  echo "Examples: "
  echo "$base vpopmail "
  echo "$base fred "
  echo
  exit 1
fi

$AWK -v input=$1 '
  BEGIN {
    cmd = "cat /etc/passwd"
    oldfs = FS
    FS=":"
    while ((cmd | getline) > 0) {
      userdb[$1] = $3
    }
    close(cmd)
    FS = oldfs

    i=0

    while( (x=index( input, "," )) > 0 ) {
      user = substr( input, 0, x-1 )
      rest = substr( input, x+1 )
      users[i++] = user
      input = rest
    }
    users[i] = input
  }
  /(^d|^m)/ {
    uid = $10
    for( key in users ) {
      id = userdb[users[key]]
      if (uid == id) print
    }
  }
'
