If stdin is a tty and dmenu is ran with the fast option then it's
impossible to close stdin because the keyboard is already grabbed.
#include <string.h>
#include <strings.h>
#include <time.h>
#include <string.h>
#include <strings.h>
#include <time.h>
#include <X11/Xlib.h>
#include <X11/Xatom.h>
#include <X11/Xlib.h>
#include <X11/Xatom.h>
+ if (fast && !isatty(0)) {
grabkeyboard();
readstdin();
} else {
grabkeyboard();
readstdin();
} else {