cpython/Python/dup2.c
Amaury Forgeot d'Arc 7955fb638a Merged revisions 85236 via svnmerge from
svn+ssh://pythondev@svn.python.org/python/branches/py3k

........
  r85236 | amaury.forgeotdarc | 2010-10-06 00:15:37 +0200 (mer., 06 oct. 2010) | 2 lines

  #9060 Let platforms without dup2() compile the replacement fonction without error.
........
2010-10-05 22:18:29 +00:00

32 lines
705 B
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;
}