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")));