X11 mouse button pressed
For a Rube Goldberg device I needed a way to know if a mouse button was pressed on the root window of an X11 screen. Here is the code for it:
#include <stdio.h> #include <stdlib.h> #include <string.h> #include <unistd.h> #include <X11/Xlib.h> #include <X11/Xutil.h> int main() { Display *dsp = XOpenDisplay( NULL ); if( !dsp ){ return 1; } int screenNumber = DefaultScreen(dsp); long eventMask = StructureNotifyMask; XSelectInput( dsp, DefaultRootWindow(dsp), eventMask ); XEvent evt; eventMask = ButtonPressMask|ButtonReleaseMask; XSelectInput(dsp, DefaultRootWindow(dsp), eventMask); // override prev do{ XNextEvent( dsp, &evt ); // calls XFlush() if ( (evt.type == ButtonRelease) || (evt.type == ButtonPress) ) exit(2); } while( 1 ); return 0; }
Compile:
gcc -lX11 -L/usr/local/include x11.c -o x11-mousebutton
Upon a mouse button being pressed it will exit 2, so using that return value in some script you can execute a command. For example, to open a CD rom drive so a domino falls over.
