fd_util: added O_NONBLOCK functions

Changed the wrappers for pipe(), socket(), accept().  On WIN32, this
does not work for pipe().

src/event_pipe.c

@@ -18,7 +18,6 @@
  */
 
 #include "event_pipe.h"
-#include "utils.h"
 #include "fd_util.h"
 
 #include <stdbool.h>
@@ -85,13 +84,9 @@ void event_pipe_init(void)
 	GIOChannel *channel;
 	int ret;
 
-	ret = pipe_cloexec(event_pipe);
+	ret = pipe_cloexec_nonblock(event_pipe);
 	if (ret < 0)
 		g_error("Couldn't open pipe: %s", strerror(errno));
-#ifndef WIN32
-	if (set_nonblocking(event_pipe[1]) < 0)
-		g_error("Couldn't set non-blocking I/O: %s", strerror(errno));
-#endif
 
 	channel = g_io_channel_unix_new(event_pipe[0]);
 	event_pipe_source_id = g_io_add_watch(channel, G_IO_IN,