FreeBSD Manual Pages
XmtBlock(3) Library Functions Manual XmtBlock(3) NAME XmtBlock() - process events in a recursive event loop. SYNOPSIS #include <Xmt/Xmt.h> void XmtBlock(Widget w, Boolean *block) ARGUMENTS INPUTS w Any widget in the application context for which events are to be processed. block A pointer to a flag that indicates when this function should return. DESCRIPTION XmtBlock() processes events in the application context of w by repeatedly calling XtAppProcessEvent() until the Boolean value pointed to by block be- comes False. Then it performs an XSync() for the display of w and calls XmUpdateDisplay() to dispatch any pending expose events. XmtBlock() is a recursive event loop, and processes events in the same way that XtAppMainLoop() does. USAGE XmtBlock() is intended for use when you want to write a function that ap- pears to the caller to block and synchronously return a value. The Xmt sim- ple dialog input routines, such as XmtAskForBoolean() are functions of this sort. True blocking is not possible in X applications because of the asyn- chronous, event-driven nature of the X programming model. XmtBlock() should generally only be called when a modal dialog is active, or when the user is in some other way prevented from repeating whatever ac- tion caused XmtBlock() to be called. Otherwise it is possible for the ap- plication to enter event loops within recursive event loops. When you use XmtBlock() you should be very sure that you know what will cause the flag block to be set to False and the loop to exit. This is usu- ally done in a callback or action procedure triggered by some user action. It is equally important that you indicate to the user what action they must take to end the modal, synchronous input. SEE ALSO Chapter 8, Utility Functions, XtAppMainLoop(), XtAppProcessEvent(). Xmt Motif Tools XmtBlock(3)
NAME | SYNOPSIS | ARGUMENTS | DESCRIPTION | USAGE | SEE ALSO
Want to link to this manual page? Use this URL:
<https://man.freebsd.org/cgi/man.cgi?query=XmtBlock&sektion=3&manpath=FreeBSD+Ports+15.1.quarterly>