### screen_running script

#!/bin/sh
if [ -z "$(screen -ls | grep $1)" ]; then
  false; # also tried return 1;
else
  true; # also tried return 0;
fi

### usage of screen_running
### the if condition is somehow wrong here

#!/bin/bash
name="irssi"

if screen_running "$name"; then
  rxvt-unicode -bg black -fg white +sb -e screen -dr "$name"
else
  rxvt-unicode -bg black -fg white +sb -e screen -mS "$name" irssi
fi

### old style of checking for a screen session
### this works

#!/bin/bash
name="irssi"

if [ -n "`screen -ls | grep $name`" ]; then
  rxvt-unicode -bg black -fg white +sb -e screen -dr "$name"
else
  rxvt-unicode -bg black -fg white +sb -e screen -mS "$name" irssi
fi