coop@tygart.cerc.wvu.wvnet.edu (Cooperate) (11/24/90)
Is that true that for every client that connects to a X server, a child server process will be created? So every client has its copy of server? thanks for comments.
mouse@LARRY.MCRCIM.MCGILL.EDU (11/25/90)
> Is that true that for every client that connects to a X server, a > child server process will be created? So every client has its copy > of server? Definitely not in general. No server I am familiar with works this way, and I have never heard of one that does. Given the way the server is required to work, it would be difficult to implement. In particular, clients are permitted to manipulate objects (windows, pixmaps, etc) created by other clients; indeed, window managers more or less *require* such capabilities, meaning that a server that forks a child for each client would probably have some major difficulty keeping the various processes in sync. Not that it's impossible, just that it's difficult enough that I would be surprised to find anyone bothering. der Mouse old: mcgill-vision!mouse new: mouse@larry.mcrcim.mcgill.edu
av@kielo.uta.fi (Arto V. Viitanen) (11/26/90)
>>>>> On 24 Nov 90 15:16:39 GMT, coop@tygart.cerc.wvu.wvnet.edu (Cooperate) said:
Cooperate> Is that true that for every client that connects to a
Cooperate> X server, a child server process will be created? So every client has
Cooperate> its copy of server? thanks for comments.
Sounds odd. How about X-terminals and PC-servers, which can only have one
process, the server itself ?
--
Arto V. Viitanen email: av@kielo.uta.fi
University Of Tampere, av@ohdake.cs.uta.fi
Finlandjimf@SABER.COM (11/27/90)
|Cooperate> Is that true that for every client that connects to a |Cooperate> X server, a child server process will be created? So every client has |Cooperate> its copy of server? No, there's usually just one process although I could see someone threading the server at some point. There's no reason why a server must run in more than one process and most do not. This design brings about the most significant limitation with most UNIX-based X servers -- they can only talk to as many clients as they have available file descriptors. This is not generally a problem since newer UNIX's generally have 64 or more file descriptors per process. |How about X-terminals and PC-servers, which can only have one |process, the server itself ? If you check I believe you'll find that some (most?) X terminals actually run a stripped-down kernel with a couple of processes, typically telnet and the X server. I'm certain that one of the major X terminal vendors (NCD?) uses or used to use this architecture, although it's been a long time since I was at that talk so I'm pretty fuzzy on the details. It's easier to do this than to modify your basic server to handle remote logins and loading of fonts via NFS. Happy hacking, jim frost saber software jimf@saber.com