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bash command or function that doesn't change the error code

Hi!

I'm trying to write a bash function or command that will not alter the error level of the previous command.

My application: I wat to create a $PS1 that outputs the error level of the last command (green=OK=0, red=error!=0) in my prompt ($PS1) within a function or script that returns the stdout colored string, I can never manage to KEEP the error level as it was....

As soon as I create a bash function or command that sets the color to grreen/red (echo/printf), they always return "0" as their error level.

Even if I try things like that as "color.sh:

Code:

#!/bin/bash

errorLevel=$?

case "$1" in

    "black")          printf '\e[30m' ;;

    "d-red")          printf '\e[31m' ;;

    "d-green")        printf '\e[32m' ;;

    "brown")          printf '\e[33m' ;;

    "d-blue")          printf '\e[34m' ;;

    "magenta")        printf '\e[35m' ;;

    "cyan")            printf '\e[36m' ;;

    "l-gray")          printf '\e[37m' ;;

    "d-gray")          printf '\e[90m' ;;

    "red")            printf '\e[91m' ;;

    "green")          printf '\e[92m' ;;

    "yellow")          printf '\e[93m' ;;

    "blue")            printf '\e[94m' ;;

    "pink")            printf '\e[95m' ;;

    "sky")            printf '\e[96m' ;;

    "white")          printf '\e[97m' ;;

    *)                printf '\e[m'  ;;

 esac

exit $errorLevel

Afterwards, the error level will always be "0" ... :(

How can I write a function or command that does not change the error level ($?)?

This is tricky. A bash script runs in a new, clean bash instance so it doesn't get the $? from the caller. A function runs in the same instance as the caller, but anything you do will set $?. This includes doing:

Code:

errorLevel=$?

Fortunately, the return value of the function can be set by the bash "return" command, so this works:

Code:

function preserve() {

  errorLevel=$?

  echo $errorLevel

  return $errorLevel

}



cat bazzle

cat: bazzle: No such file or directory

preserve

1

echo $?

1

You saved my life (... and my error level :P ). Thanks a lot!