sysdeps/unix/sysv/linux/readlink.c

   1 /* Read value of a symbolic link.  Linux version.
   2    Copyright (C) 2011-2024 Free Software Foundation, Inc.
   3    This file is part of the GNU C Library.
   4
   5    The GNU C Library is free software; you can redistribute it and/or
   6    modify it under the terms of the GNU Lesser General Public
   7    License as published by the Free Software Foundation; either
   8    version 2.1 of the License, or (at your option) any later version.
   9
  10    The GNU C Library is distributed in the hope that it will be useful,
  11    but WITHOUT ANY WARRANTY; without even the implied warranty of
  12    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  13    Lesser General Public License for more details.
  14
  15    You should have received a copy of the GNU Lesser General Public
  16    License along with the GNU C Library.  If not, see
  17    <https://www.gnu.org/licenses/>.  */
  18
  19 #include <unistd.h>
  20 #include <fcntl.h>
  21 #include <sysdep.h>
  22
  23 /* Read the contents of the symbolic link PATH into no more than
  24    LEN bytes of BUF.  The contents are not null-terminated.
  25    Returns the number of characters read, or -1 for errors.  */
  26 ssize_t
  27 __readlink (const char *path, char *buf, size_t len)
  28 {
  29 #ifdef __NR_readlink
  30   return INLINE_SYSCALL_CALL (readlink, path, buf, len);
  31 #else
  32   return INLINE_SYSCALL_CALL (readlinkat, AT_FDCWD, path, buf, len);
  33 #endif
  34 }
  35 weak_alias (__readlink, readlink)