Tell me more ×
Unix & Linux Stack Exchange is a question and answer site for users of Linux, FreeBSD and other Un*x-like operating systems.. It's 100% free, no registration required.
up vote 5 down vote favorite

We are using Oracle Secure Global desktop to provide remote access to the Solaris desktop. It sets the DISPLAY variable to unix:10.0.

It seems to be working as if the DISPLAY was set to localhost:10.0. What does "unix" mean here?

Is it a common usage or something specific to SGD? As far as I know, usually DISPLAY is set in the form [hostname or IP]:[screen].

share|improve this question
2  
Looks to me like unix just might be the hostname of the computer X11 is sending it's display to. – MaxMackie Sep 9 '11 at 14:43

1 Answer

up vote 2 down vote

It's reasonably common to see this. It means "use a unix-domain socket" instead of a TCP/IP socket. These "unix domain" sockets show up in the file system. For instance, on my old Slackware 11.0 system, the Unix domain socket has the file name /tmp/.X11-unix/X0

12 % ls -ltr /tmp/.X11-unix
total 0
srwxrwxrwx 1 root users 0 2011-07-19 18:07 X0=

Note the 's' in the mode: that's "socket". I seem to recall other X11s putting the unix-domain socket in /tmp/ directly.

Using a unix-domain socket for X11 traffic can be quite a bit faster, and probably a lot more secure than flinging the traffic over TCP-IP

share|improve this answer
Shouldn't it be unix/:10 then? The format is [transport/]host:[:]server[.screen], with host blank for local. (The extra optional : is to support the old method for differentiating tcp from decnet) – Random832 Sep 9 '11 at 16:33
1  
@Random832 I'm not sure what the exact syntax is, but X.org Xlib accepts unix:0 as a synonym of unix/:0. – Gilles Sep 9 '11 at 23:46
1  
To add to this answer: using a unix socket means that the X server and the client are running on the same machine. Under most modern X implementations, this allows the client and the server to operate via shared memory instead of via network-style messages. Shared memory enables many optimisations, which are especially important when viewing video or drawing 3D images. – Gilles Sep 9 '11 at 23:48
@Gilles Is this documented anywhere? I went and looked up the source (what I thought was the source), since the format wasn't well-documented, and it doesn't seem to support this being a synonym – Random832 Sep 10 '11 at 2:39
I was under the impression that those optimisations are triggered whenever the local host is used as a display server, even if TCP is used. I remember reading this in some manual back in the XFree86 days. – Alexios May 2 '12 at 6:55

Your Answer

 
discard

By posting your answer, you agree to the privacy policy and terms of service.

Not the answer you're looking for? Browse other questions tagged or ask your own question.