XLIB FUNCTIONS XOpenDisplay(3x11)
NAME
XOpenDisplay, XCloseDisplay - connect or disconnect to X
server SYNTAXcc [ flag... ] file... -lX11 [ library... ]
Display *XOpenDisplay(char *display_name);
int XCloseDisplay(Display *display); ARGUMENTS display Specifies the connection to the X server.display_name
Specifies the hardware display name, which deter-
mines the display and communications domain to beused. On a POSIX-conformant system, if the
display_name is NULL, it defaults to the value of
the DISPLAY environment variable.DESCRIPTION
The XOpenDisplay function returns a Display structure that
serves as the connection to the X server and that containsall the information about that X server. XOpenDisplay con-
nects your application to the X server through TCP or DECnetcommunications protocols, or through some local inter-
process communication protocol. If the hostname is a host machine name and a single colon (:) separates the hostnameand display number, XOpenDisplay connects using TCP streams.
If the hostname is not specified, Xlib uses whatever it believes is the fastest transport. If the hostname is a host machine name and a double colon (::) separates thehostname and display number, XOpenDisplay connects using
DECnet. A single X server can support any or all of these transport mechanisms simultaneously. A particular Xlib implementation can support many more of these transport mechanisms.If successful, XOpenDisplay returns a pointer to a Display
structure, which is defined in
. If XOpen- Display does not succeed, it returns NULL. After a success-
ful call to XOpenDisplay, all of the screens in the display
can be used by the client. The screen number specified inthe display_name argument is returned by the DefaultScreen
macro (or the XDefaultScreen function). You can access ele-
ments of the Display and Screen structures only by using the information macros or functions. For information about using macros and functions to obtain information from the Display structure, see section 2.2.1. X Version 11 Last change: libX11 1.3.5 1XLIB FUNCTIONS XOpenDisplay(3x11)
The XCloseDisplay function closes the connection to the X server for the display specified in the Display structureand destroys all windows, resource IDs (Window, Font, Pix-
map, Colormap, Cursor, and GContext), or other resources that the client has created on this display, unless theclose-down mode of the resource has been changed (see
XSetCloseDownMode). Therefore, these windows, resource IDs, and other resources should never be referenced again or an error will be generated. Before exiting, you should call XCloseDisplay explicitly so that any pending errors are reported as XCloseDisplay performs a final XSync operation. XCloseDisplay can generate a BadGC error.SEE ALSO
AllPlanes(3x11), XFlush(3x11), XSetCloseDownMode(3x11)Xlib - C Language X Interface
ATTRIBUTES
See attributes(5) for descriptions of the following attri-
butes:____________________________________________________________
| ATTRIBUTE TYPE | ATTRIBUTE VALUE |
|_____________________________|_____________________________|
| Availability | x11/library/libx11 ||_____________________________|_____________________________|
| Interface Stability | Committed ||_____________________________|_____________________________|
| MT-Level | See XInitThreads(3X11) |
|_____________________________|_____________________________|
X Version 11 Last change: libX11 1.3.5 2