minix/lib/nbsd_libc/sys-minix/dup2.c
Gianluca Guida 4f294c247f Add NBSDLibc Minix specific files.
This patch mainly copies and modifies files existing in
the current libc implementing minix specific functions.

To keep consisten with the NetBSD libc, we remove 
namespace stubs and we use "namespace.h" and weak
links.
2011-02-17 17:11:09 +00:00

35 lines
601 B
C

#include <sys/cdefs.h>
#include "namespace.h"
#include <lib.h>
#include <fcntl.h>
#include <unistd.h>
#ifdef __weak_alias
__weak_alias(dup2, _dup2)
#endif
PUBLIC int dup2(fd, fd2)
int fd, fd2;
{
/* The behavior of dup2 is defined by POSIX in 6.2.1.2 as almost, but not
* quite the same as fcntl.
*/
if (fd2 < 0 || fd2 > OPEN_MAX) {
errno = EBADF;
return(-1);
}
/* Check to see if fildes is valid. */
if (fcntl(fd, F_GETFL) < 0) {
/* 'fd' is not valid. */
return(-1);
} else {
/* 'fd' is valid. */
if (fd == fd2) return(fd2);
close(fd2);
return(fcntl(fd, F_DUPFD, fd2));
}
}