dwm-tag update

[ChrisTitusTech]

Event-Driven Polybar Tag Updates

Overview

Modified DWM and the polybar dwm-tags script to use event-driven updates instead of polling every second. This reduces CPU usage and provides instant visual feedback when switching tags.

How It Works

1. DWM Changes (dwm.c)

• Added updatepolybar() function that sets an X property DWM_TAG_UPDATE on the root window
• Called updatepolybar() in key functions:
  • view() - when switching to a different tag
  • tag() - when moving a window to a tag
  • toggletag() - when toggling tag membership
  • toggleview() - when toggling tag visibility

2. Script Changes (polybar/scripts/dwm-tags.sh)

• Added --tail mode that listens for X property changes using xprop -spy
• Refactored tag generation into update_tags() function
• When run with --tail, the script:
  1. Outputs initial state
  2. Listens for DWM_TAG_UPDATE property changes
  3. Updates display whenever the property changes

3. Polybar Config (polybar/themes/minimal/modules/dwm-tags.ini)

• Changed from interval = 1 to tail = true
• Added --tail argument to the script execution

Benefits

• Lower CPU usage: No more polling every second
• Instant updates: Visual changes happen immediately when tags switch
• More efficient: Only updates when something actually changes
• Backward compatible: Script still works in polling mode without --tail argument

To Apply Changes

1. Recompile and install DWM: sudo make clean install
2. Restart DWM (typically Mod+Shift+R or re-login)
3. Restart polybar: ~/.local/share/dwm-titus/polybar/launch.sh

The polybar module will now update instantly when you switch workspaces instead of polling every second.