dup2.c

来自「Linux下的TFTP源代码」· C语言 代码 · 共 26 行

/*
 * dup2.c
 *
 * Ersatz dup2() for really ancient systems
 */

#include "config.h"

int dup2(int oldfd, int newfd)
{
  int rv, nfd;

  close(newfd);

  nfd = rv = dup(oldfd);

  if (rv >= 0 && rv != newfd) {
    rv = dup2(oldfd, newfd);
    close(nfd);
  }

  return rv;
}