Skip to main content

Browse the archive

Staging
v0.5.1
https://github.com/python/cpython
09 December 2020, 11:06:31 UTC
Revision 5a045b9f5493b12bc8421b55ffff10b6572bc22c authored by Ezio Melotti on 29 February 2012, 09:48:44 UTC, committed by Ezio Melotti on 29 February 2012, 09:48:44 UTC 
#10713: Improve documentation for \b and \B and add a few tests.  Initial patch and tests by Martin Pool.
1 parent 62417a0
Raw File
Tip revision: 5a045b9f5493b12bc8421b55ffff10b6572bc22c authored by Ezio Melotti on 29 February 2012, 09:48:44 UTC
#10713: Improve documentation for \b and \B and add a few tests. Initial patch and tests by Martin Pool.
Tip revision: 5a045b9
dup2.c 
/*
 * Public domain dup2() lookalike
 * by Curtis Jackson @ AT&T Technologies, Burlington, NC
 * electronic address:  burl!rcj
 *
 * dup2 performs the following functions:
 *
 * Check to make sure that fd1 is a valid open file descriptor.
 * Check to see if fd2 is already open; if so, close it.
 * Duplicate fd1 onto fd2; checking to make sure fd2 is a valid fd.
 * Return fd2 if all went well; return BADEXIT otherwise.
 */

#include <fcntl.h>
#include <unistd.h>

#define BADEXIT -1

int
dup2(int fd1, int fd2)
{
	if (fd1 != fd2) {
		if (fcntl(fd1, F_GETFL) < 0)
			return BADEXIT;
		if (fcntl(fd2, F_GETFL) >= 0)
			close(fd2);
		if (fcntl(fd1, F_DUPFD, fd2) < 0)
			return BADEXIT;
	}
	return fd2;
}
back to top