Launch separate Emacs process for Notmuch UI with own appname+icon, works with GNOME Shell

notmuch-launch.sh

#! /bin/bash
#
# Copyright (C) 2012 Adrian Perez <aperez@igalia.com>
# Distributed under terms of the MIT license.
#
# Install as:
#   ~/.local/bin/notmuch-launch
# Dependencies:
#   wmctrl (http://tomas.styblo.name/wmctrl)
#   xsetclasshint program
#   Emacs with X-Window systems support
#   Notmuch Emacs UI that works with "emacs -f notmuch"
#

PATH="${PATH}:${HOME}/.local/bin"
export PATH

emacs --name Notmuch --no-splash -f notmuch &

tries=10
windowid=''
while [[ -z ${windowid} && ${tries} -gt 0 ]] ; do
	sleep 0.75
	while read -a wmline ; do
		if [[ ${wmline[2]} = Notmuch.Emacs ]] ; then
			windowid=${wmline[0]}
		fi
	done < <( wmctrl -l -x )
	(( tries-- ))
done

if [[ -n ${windowid} ]] ; then
	xsetclasshint ${windowid} Notmuch Notmuch
fi

notmuch.desktop

[Desktop Entry]
Name=Notmuch
GenericName=Mail reader and indexer
Comment=Edit text
Exec=/home/user/.local/bin/notmuch-launch
Icon=evolution
Type=Application
Terminal=false
Categories=Internet;Email;
StartupWMClass=Notmuch
#
# Usage:
#
#   Create the ~/.local.share/applications/ directory if needed
#   Copy to ~/.local/share/applications/notmuch.desktop
#   Edit the "Exec=" line to point to the location of notmuch-launch
#

xsetclasshint.c

/*
 * xsetclasshint.c
 * Copyright (C) 2012 Adrian Perez <aperez@igalia.com>
 * Distributed under terms of the MIT license.
 *
 * Build with:
 *   cc -o xsetclasshint xsetclasshint.c `pkg-config x11 --libs`
 *
 * Install compiled program to:
 *   ~/.local/bin/xsetclasshint
 */

#include <X11/X.h>
#include <X11/Xlib.h>
#include <X11/Xutil.h>
#include <stdlib.h>
#include <limits.h>
#include <stdio.h>
#include <errno.h>

int
main (int argc, char **argv)
{
  XClassHint hint = { NULL, NULL };
  Display *disp = NULL;
  Window w = 0x0;

  if (argc != 4)
    {
      fprintf (stderr,
               "Usage: %s window-id window-name window-class\n",
               argv[0]);
      exit (EXIT_FAILURE);
    }

  if ((w = (Window) strtoul (argv[1], NULL, 0)) == ULONG_MAX &&
      errno == ERANGE)
    {
      fprintf (stderr, "%s: window-id '%s' invalid\n", argv[0], argv[1]);
      exit (EXIT_FAILURE);
    }

  if ((disp = XOpenDisplay (NULL)) == NULL)
    {
      fprintf (stderr, "%s: Could not open X display\n", argv[0]);
      exit (EXIT_FAILURE);
    }

  hint.res_name  = argv[2];
  hint.res_class = argv[3];

  XSetClassHint (disp, w, &hint);
  XCloseDisplay (disp);

  return EXIT_SUCCESS;;
}