Mercurial > sdl-ios-xcode
view docs/man3/SDL_SetEventFilter.3 @ 865:92615154bb68
Date: Sun, 29 Feb 2004 15:14:22 +0200
From: Martin_Storsj
Subject: Dynamic loading of ALSA
I recently discovered that SDL can dynamically load ESD and aRts, and
made a patch which adds this same functionality to ALSA.
The update for configure.in isn't too good (it should e.g. look for
libasound.so in other directories than /usr/lib), because I'm not too
good at shellscripting and autoconf.
The reason for using dlfcn.h and dlopen instead of SDL_LoadLibrary and
SDL_LoadFunction is that libasound uses versioned symbols, and it is
necessary to load the correct version using dlvsym. This isn't probably
any real portability issue, because ALSA is linux-only.
author | Sam Lantinga <slouken@libsdl.org> |
---|---|
date | Tue, 02 Mar 2004 12:49:16 +0000 |
parents | e5bc29de3f0a |
children | 546f7c1eb755 |
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.TH "SDL_SetEventFilter" "3" "Tue 11 Sep 2001, 22:59" "SDL" "SDL API Reference" .SH "NAME" SDL_SetEventFilter\- Sets up a filter to process all events before they are posted to the event queue\&. .SH "SYNOPSIS" .PP \fB#include "SDL\&.h" .sp \fBvoid \fBSDL_SetEventFilter\fP\fR(\fBSDL_EventFilter filter\fR); .SH "DESCRIPTION" .PP This function sets up a filter to process all events before they are posted to the event queue\&. This is a very powerful and flexible feature\&. The filter is prototyped as: .PP .nf \f(CWtypedef int (*SDL_EventFilter)(const SDL_Event *event);\fR .fi .PP If the filter returns \fB1\fR, then the event will be added to the internal queue\&. If it returns \fB0\fR, then the event will be dropped from the queue\&. This allows selective filtering of dynamically\&. .PP There is one caveat when dealing with the \fBSDL_QUITEVENT\fP event type\&. The event filter is only called when the window manager desires to close the application window\&. If the event filter returns 1, then the window will be closed, otherwise the window will remain open if possible\&. If the quit event is generated by an interrupt signal, it will bypass the internal queue and be delivered to the application at the next event poll\&. .PP .RS \fBNote: .PP Events pushed onto the queue with \fI\fBSDL_PushEvent\fP\fR or \fI\fBSDL_PeepEvents\fP\fR do not get passed through the event filter\&. .RE .PP .RS \fBNote: .PP \fIBe Careful!\fP The event filter function may run in a different thread so be careful what you do within it\&. .RE .SH "SEE ALSO" .PP \fI\fBSDL_Event\fR\fR, \fI\fBSDL_GetEventFilter\fP\fR, \fI\fBSDL_PushEvent\fP\fR ...\" created by instant / docbook-to-man, Tue 11 Sep 2001, 22:59