Is there a linux command to determine the window IDs associated with a given process ID?

Question

Given a process iD of XX, I\'d like to have a list of any window id\'s where _NET_WM_PID = XX. Even better would be the oldest still active window id if possible.

I

Answer 1

Here is a list of all the X11 window management commands you will ever need.

You can get the window ID associated with a process ID using wmctrl in a script like this:

#!/usr/bin/env bash
# 
# File:
#   getwindidbypid
# 
# Description:
#   Get the ID of a window by PID (if the process has a window).
# 
# Usage:
#   getwindidbypid 
# 

while IFS= read line; do
  if [[ "${line}" =~ (0x)([0-9a-z]+)([ ][- ][0-9]+[ ])([0-9]*) ]]; then
    winId="${BASH_REMATCH[1]}${BASH_REMATCH[2]}"
    pid="${BASH_REMATCH[4]}"
    if [[ "${pid}" -eq "${1}" ]]; then
      WIND_IDS+=("${winId}")
    fi
  fi
done < <(wmctrl -lp)

if [ "${#WIND_IDS[@]}" -gt 0 ]; then
  echo "${WIND_IDS[@]}"
fi

Example:

user ~ $  getwindidbypid 37248
0x05a00012