1#include <wasi/api.h>
2#include <__errno.h>
3#include <__function___isatty.h>
4
5int __isatty(int fd) {
6 __wasi_fdstat_t statbuf;
7 int r = __wasi_fd_fdstat_get(fd, &statbuf);
8 if (r != 0) {
9 errno = r;
10 return 0;
11 }
12
13 // A tty is a character device that we can't seek or tell on.
14 if (statbuf.fs_filetype != __WASI_FILETYPE_CHARACTER_DEVICE ||
15 (statbuf.fs_rights_base & (__WASI_RIGHTS_FD_SEEK | __WASI_RIGHTS_FD_TELL)) != 0) {
16 errno = __WASI_ERRNO_NOTTY;
17 return 0;
18 }
19
20 return 1;
21}
22extern __typeof(__isatty) isatty __attribute__((weak, alias("__isatty")));