Path: utzoo!utgpu!news-server.csri.toronto.edu!cs.utexas.edu!swrinde!ucsd!ucbvax!bloom-beacon!LARRY.MCRCIM.MCGILL.EDU!mouse
From: mouse@LARRY.MCRCIM.MCGILL.EDU
Newsgroups: comp.windows.x
Subject: Re:  Resources & Forking
Message-ID: <9012030508.AA19022@Larry.McRCIM.McGill.EDU>
Date: 3 Dec 90 05:08:06 GMT
Sender: daemon@athena.mit.edu (Mr Background)
Organization: The Internet
Lines: 49

> 1)  Is it possible to use X to read an X resource files without being
>     connected to a server?

Yes, provided you really mean "file".

>     If it is possible, how would I do it??

The R4 way would be to use...

	To retrieve a database from disk, use XrmGetFileDatabase.
	
	XrmDatabase XrmGetFileDatabase(filename)
	     char *filename;
	
	filename  Specifies the resource database file name.

I don't know whether R3 is capable of similar things, though I would
assume it is.

> 2)  If I open a display, then fork I presume both processes are
>     sharing a connection to the server.

(I assume you're using UNIX.)  Yes.

>     If one process only wishes to read X resource files is there any
>     problem with not explicitly synchronizing the processes?  Or does
>     any database operation require server contact?

As you may have gathered from the above and from other postings, server
access is not necessary for reading resource files.  Leaving the
connection open in both parent and child will not harm anything,
*provided* that only one of the two processes ever tries to do anything
with it after the fork.  (Two processes both trying to use the same
server connection will almost certainly get Xlib in a hopelessly
confused state.  You don't want to do it[%].)

[%] Unless, of course, you're willing to take on the task of putting
    the necessary synchronization code into Xlib.  This would be a
    major effort.

Actually, you don't even want to XCloseDisplay() in the process that
won't be using the connection; this could flush buffered data twice.
Either ignore the X connection entirely or close its file descriptor
without letting Xlib know: close(XConnectionNumber(dpy)).

					der Mouse

			old: mcgill-vision!mouse
			new: mouse@larry.mcrcim.mcgill.edu