📄 xaddconnectionwatch.html
字号:
<HTML><HEAD><TITLE>Xlib Programming Manual: XAddConnectionWatch</TITLE></HEAD><BODY><H1 ALIGN=center>XAddConnectionWatch</H1><!.IN "XWatchProc" "" "@DEF@"><!.IN "XAddConnectionWatch" "" "@DEF@"><A NAME="XWatchProc"></A><H2>Syntax</H2><CODE><PRE>typedef void (*XConnectionWatchProc)(<B>display</B>, <B>client_data</B>, <B>fd</B>, <B>opening</B>, <B>watch_data</B>) <A HREF="opening.html#Display">Display</A> *<B>display</B>; XPointer <B>client_data</B>; int <B>fd</B>; Bool <B>opening</B>; XPointer *<B>watch_data</B>;Status XAddConnectionWatch(<B>display</B>, <B>procedure</B>, <B>client_data</B>) <A HREF="opening.html#Display">Display</A> *<B>display</B>; XWatchProc <B>procedure</B>; XPointer <B>client_data</B>;</PRE></CODE><H2>Arguments</H2><TABLE><TR><TD> <B>display</B><TD> Specifies the connection to the X server.<TR><TD> <B>procedure</B><TD> Specifies the procedure to be called.<TR><TD> <B>client_data</B><TD> Specifies the additional client data.</TABLE><H2>Description</H2>The<B>XAddConnectionWatch()</B>function registers a procedure to be called each time Xlib opens or closes aninternal connection for the specified display. The procedure is passed thedisplay, the specified client_data, the file descriptor for the connection,a Boolean indicating whether the connection is being opened or closed, and apointer to a location for private watch data. If opening is<B>True</B>,the procedure can store a pointer to private data in the location pointedto by watch_data;when the procedure is later called for this same connection and opening is<B>False</B>,the location pointed to by watch_data will hold this same private data pointer.<P>This function can be called at any time after a display is opened.If internal connections already exist, the registered procedure willimmediately be called for each of them, before<B>XAddConnectionWatch()</B>returns.<B>XAddConnectionWatch()</B>returns a nonzero status if the procedure is successfully registered;otherwise, it returns zero.<P>The registered procedure should not call any Xlib functions.If the procedure directly or indirectly causes the state of internalconnections or watch procedures to change, the result is not defined.If Xlib has been initialized for threads, the procedure is called withthe display locked and the result of a call by the procedure to anyXlib function that locks the display is not defined unless the executingthread has externally locked the display using<B><A HREF="XLockDisplay.html">XLockDisplay()</A></B>.<H2>See also</H2><B><A HREF="XRemoveConnectionWatch.html">XRemoveConnectionWatch()</A></B>,<B><A HREF="XProcessInternalConnection.html">XProcessInternalConnection()</A></B>,<B><A HREF="XInternalConnectionNumbers.html">XInternalConnectionNumbers()</A></B>,"<A HREF="internal-connections.html">Internal Connections</A>".<HR><ADDRESS><A HREF="http://tronche.com/">Christophe Tronche</A>, <A HREF="mailto:ch.tronche@computer.org">ch.tronche@computer.org</A></ADDRESS></BODY></HTML>⌨️ 快捷键说明
复制代码
Ctrl + C
搜索代码
Ctrl + F
全屏模式
F11
切换主题
Ctrl + Shift + D
显示快捷键
?
增大字号
Ctrl + =
减小字号
Ctrl + -