2000-05-10  Michael Natterer  <mitch@gimp.org>

	Another try to get the signal/dead child recovery stuff right.

	Could the brave signal crew (TM) (Austin, Garry, Raphael, Tim)
	please do bad tests to the new code? I removed all strange
	constants (SA_NODEFER etc.) and used only glib and POSIX stuff.

	* app/main.c
	* libgimp/gimp.c:
	- Call gimp_signal_private() with no flags to enforce a proper
	  sigaction() behaviour (block signals while handler is active).
	- Removed the reentrancy guards from the handlers.
	- Renamed the handlers.
	- Ignore SIGPIPE in the app and in plugins.
	- Re-introduced the SIGCHLD handler because it should work
	  now. Also added a SIGCHLD handler to libgimp/gimp.c.

	* app/errors.c
	* libgimp/gimp.c: in the signal handler, unblock all signals
	with sigprocmask() before calling g_on_error_query() because
	gdb otherwise inherits the blocked signals and does nothing.
	Wrapped the statements with "if (TRUE) { }" blocks so it's
	easy to make the stack trace a command line option.

	* app/plug_in.c
	* libgimp/gimp.c: listen for G_IO_ERR and G_IO_HUP on the read
	channels. In the app, pop up an error message and clean up the
	plugin. In plugins, clean up and exit.

	* libgimp/gimpwire.c: removed the "plug-in chrashed?" message
	and print the program's name with all error messages.

	* plug-ins/helpbrowser/helpbrowser.c: typo.