Normally bits like this would be considered implementation details, but
in this case, `X_OK`, `W_OK`, and `R_OK` line up with `S_IXOTH`,
`S_IWOTH`, and `S_IROTH` on other systems, and those bits do have
well-known values.
#define F_GETFD (1)
#define F_GETFL (3)
#define F_LOCK 1
-#define F_OK 0
+#define F_OK (0)
#define F_SETFD (2)
#define F_SETFL (4)
#define F_TEST 3
#define RS_HIPRI 0x01
#define RUSAGE_CHILDREN 2
#define RUSAGE_SELF 1
-#define R_OK 1
+#define R_OK (4)
#define SARMAG 8
#define SB 250
#define SCHAR_MAX 127
#define WONT 252
#define WORD_BIT 32
#define WRQ 02
-#define W_OK 2
-#define X_OK 4
+#define W_OK (2)
+#define X_OK (1)
#define YESEXPR 0x50000
#define YESSTR 0x50002
#define YXDOMAIN ns_r_yxdomain
#include <__seek.h>
-#define F_OK 0
-#define R_OK 1
-#define W_OK 2
-#define X_OK 4
+#define F_OK (0)
+#define X_OK (1)
+#define W_OK (2)
+#define R_OK (4)
#ifdef __cplusplus
extern "C" {