ecore_fd_handler_example.c

This example shows how to setup and use an fd_handler.

This example shows how to setup and use an fd_handler. See the explanation here.

/*
 * gcc -o ecore_fd_handler_example ecore_fd_handler_example.c `pkg-config --cflags --libs ecore`
 */
 
#include <Ecore.h>
#include <unistd.h>
 
struct context
{
   Ecore_Fd_Handler *handler;
   Ecore_Timer      *timer;
};
 
static void
_fd_prepare_cb(void *data EINA_UNUSED, Ecore_Fd_Handler *handler EINA_UNUSED)
{
   printf("prepare_cb called.\n");
}
 
static Eina_Bool
_fd_handler_cb(void *data, Ecore_Fd_Handler *handler)
{
   struct context *ctxt = data;
   char buf[1024];
   size_t nbytes;
   int fd;
 
   if (ecore_main_fd_handler_active_get(handler, ECORE_FD_ERROR))
     {
        printf("An error has occurred. Stop watching this fd and quit.\n");
        ecore_main_loop_quit();
        ctxt->handler = NULL;
        return ECORE_CALLBACK_CANCEL;
     }
 
   fd = ecore_main_fd_handler_fd_get(handler);
   nbytes = read(fd, buf, sizeof(buf));
   if (nbytes == 0)
     {
        printf("Nothing to read, exiting...\n");
        ecore_main_loop_quit();
        ctxt->handler = NULL;
        return ECORE_CALLBACK_CANCEL;
     }
   buf[nbytes - 1] = '\0';
 
   printf("Read %zd bytes from input: \"%s\"\n", nbytes - 1, buf);
 
   return ECORE_CALLBACK_RENEW;
}
 
static Eina_Bool
_timer_cb(void *data EINA_UNUSED)
{
   printf("Timer expired after 5 seconds...\n");
 
   return ECORE_CALLBACK_RENEW;
}
 
int
main(void)
{
   struct context ctxt = {0};
 
   if (!ecore_init())
     {
        printf("ERROR: Cannot init Ecore!\n");
        return -1;
     }
 
   ctxt.handler = ecore_main_fd_handler_add(STDIN_FILENO,
                                            ECORE_FD_READ | ECORE_FD_ERROR,
                                            _fd_handler_cb,
                                            &ctxt, NULL, NULL);
   ecore_main_fd_handler_prepare_callback_set(ctxt.handler, _fd_prepare_cb, &ctxt);
   ctxt.timer = ecore_timer_add(5, _timer_cb, &ctxt);
 
   printf("Starting the main loop. Type anything and hit <enter> to "
          "activate the fd_handler callback, or CTRL+d to shutdown.\n");
 
   ecore_main_loop_begin();
 
   if (ctxt.handler)
     ecore_main_fd_handler_del(ctxt.handler);
 
   if (ctxt.timer)
     ecore_timer_del(ctxt.timer);
 
   ecore_shutdown();
 
   return 0;
}