libc-top-half/musl/src/unistd/dup3.c

   1 #define _GNU_SOURCE
   2 #include <unistd.h>
   3 #include <errno.h>
   4 #include <fcntl.h>
   5 #include "syscall.h"
   6
   7 int __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 & O_CLOEXEC) {
  13                 while ((r=__syscall(SYS_dup3, old, new, flags))==-EBUSY);
  14                 if (r!=-ENOSYS) return __syscall_ret(r);
  15         }
  16         while ((r=__syscall(SYS_dup2, old, new))==-EBUSY);
  17         if (flags & O_CLOEXEC) __syscall(SYS_fcntl, new, F_SETFD, FD_CLOEXEC);
  18 #else
  19         while ((r=__syscall(SYS_dup3, old, new, flags))==-EBUSY);
  20 #endif
  21         return __syscall_ret(r);
  22 }
  23
  24 weak_alias(__dup3, dup3);