xref: /third_party/musl/src/unistd/dup3.c (revision 570af302)
1#define _GNU_SOURCE
2#include <unistd.h>
3#include <errno.h>
4#include <fcntl.h>
5#include "syscall.h"
6
7int __dup3(int old, int new, int flags)
8{
9	int r;
10#ifdef SYS_dup2
11	if (old==new) return __syscall_ret(-EINVAL);
12	if (flags) {
13		while ((r=__syscall(SYS_dup3, old, new, flags))==-EBUSY);
14		if (r!=-ENOSYS) return __syscall_ret(r);
15		if (flags & ~O_CLOEXEC) return __syscall_ret(-EINVAL);
16	}
17	while ((r=__syscall(SYS_dup2, old, new))==-EBUSY);
18	if (r >= 0 && (flags & O_CLOEXEC))
19		__syscall(SYS_fcntl, new, F_SETFD, FD_CLOEXEC);
20#else
21	while ((r=__syscall(SYS_dup3, old, new, flags))==-EBUSY);
22#endif
23	return __syscall_ret(r);
24}
25
26weak_alias(__dup3, dup3);
27