Gtk: disabled ^Z suspension on Unix for the time being

* This has always been broken as Gtk will not hide the
  window before suspending.
* It has been deemed to complicated to implement at the moment.
  Even if we can catch SIGTSTP (not that trivial), it seems to be
  impossible - at least without some lower level Xlib interaction -
  to hide the program window before raising SIGTSTP.
* Even if everything worked, it is unclear whether it is actually
  desirable to suspend a GUI application - ^Z may be pressed accidentally
  and it will be inconvenient to resume the job.
  So we would additionally have to check for the existence of
  an attached console.

3 files changed, 18 insertions, 13 deletions

diff --git a/TODO b/TODO
index ca073c3..b1d98c2 100644
--- a/TODO
+++ b/TODO
@@ -80,6 +80,21 @@ Known Bugs:
    logging system.
  * Out-of-tree builds are broken.
    See contrib/scintilla.am.
+ * Gtk on Unix: On ^Z, we do not suspend properly. The window is still shown.
+   Perhaps we should try to catch SIGTSTP?
+   This does not work with g_unix_signal_add(), though, so any
+   workaround would be tricky.
+   We could create a pipe via g_unix_open_pipe() which we
+   write to using write() in a normal signal handler.
+   We can then add a watcher using g_unix_fd_add() which will
+   hide the main window.
+   Unfortunately, it is also not trivial to get notified when
+   the window has really been hidden/unrealized.
+   Even if everything worked, it might well be annoying if
+   you accidentally suspend your instance while not being
+   connected to a terminal.
+   Suspension from the command-line has therefore been disabled
+   on Gtk for the time being.
 
 Features:
  * Auto-indention could be implemented via context-sensitive
diff --git a/src/cmdline.c b/src/cmdline.c
index 018998e..5c080af 100644
--- a/src/cmdline.c
+++ b/src/cmdline.c
@@ -398,13 +398,12 @@ teco_state_process_edit_cmd(teco_machine_t *ctx, teco_machine_t *parent_ctx, gch
 		}
 		return TRUE;
 
-#ifdef SIGTSTP
+#if !defined(INTERFACE_GTK) && defined(SIGTSTP)
 	case TECO_CTL_KEY('Z'):
 		/*
-		 * <CTL/Z> does not raise signal if handling of
+		 * <CTL/Z> does not automatically raise signal if handling of
 		 * special characters temporarily disabled in terminal
-		 * (Curses), or command-line is detached from
-		 * terminal (GTK+).
+		 * (Curses), or the actual input is detached from terminal (GTK+).
 		 * This does NOT change the state of the popup window.
 		 */
 		raise(SIGTSTP);
diff --git a/src/interface-gtk/interface.c b/src/interface-gtk/interface.c
index 154c950..104bb89 100644
--- a/src/interface-gtk/interface.c
+++ b/src/interface-gtk/interface.c
@@ -1052,15 +1052,6 @@ teco_interface_event_loop(GError **error)
 	 * closing the window if supported by this version of glib.
 	 * Note that this replaces SciTECO's default SIGTERM handler
 	 * so it will additionally raise(SIGINT).
-	 *
-	 * FIXME: On ^Z, we do not suspend properly. The window is still shown.
-	 * Perhaps we should try to catch SIGTSTP?
-	 * This does not work with g_unix_signal_add(), though, so any
-	 * workaround would be tricky.
-	 * We could create a pipe via g_unix_open_pipe() which we
-	 * write to using write() in a normal signal handler.
-	 * We can then add a watcher using g_unix_fd_add() which will
-	 * hide the main window.
 	 */
 #ifdef G_OS_UNIX
 	g_unix_signal_add(SIGTERM, teco_interface_sigterm_handler, NULL);