tyfuzz: instead of writing to /dev/null, just do not write

src/bin/termpty.c

@@ -1256,7 +1256,7 @@ termpty_write(Termpty *ty, const char *input, int len)
 #else
    int fd = ty->fd;
 #if defined(ENABLE_FUZZING)
-   fd = ty->fd_dev_null;
+   return;
 #endif
    if (fd < 0) return;
    if (write(fd, input, len) < 0)

src/bin/termpty.h

@@ -170,9 +170,6 @@ struct _Termpty
    int fd, slavefd;
 #if defined(ENABLE_TESTS)
    struct ty_sb write_buffer;
-#endif
-#if defined(ENABLE_FUZZING)
-   int fd_dev_null;
 #endif
    struct {
       int curid;

src/bin/tyfuzz.c

@@ -263,10 +263,6 @@ _termpty_init(Termpty *ty, Config *config)
    assert(ty->screen2);
    ty->circular_offset = 0;
    ty->fd = STDIN_FILENO;
-#if defined(ENABLE_FUZZING)
-   ty->fd_dev_null = open("/dev/null", O_WRONLY|O_APPEND);
-   assert(ty->fd_dev_null >= 0);
-#endif
    ty->hl.bitmap = calloc(1, HL_LINKS_MAX / 8); /* bit map for 1 << 16 elements */
    assert(ty->hl.bitmap);
    /* Mark id 0 as set */
@@ -281,9 +277,6 @@ _termpty_shutdown(Termpty *ty)
 #if defined(ENABLE_TESTS)
    ty_sb_free(&ty->write_buffer);
 #endif
-#if defined(ENABLE_FUZZING)
-   close(ty->fd_dev_null);
-#endif
 }
 
 int