1  /* Copyright (C) 1991-2023 Free Software Foundation, Inc.
       2     This file is part of the GNU C Library.
       3  
       4     The GNU C Library is free software; you can redistribute it and/or
       5     modify it under the terms of the GNU Lesser General Public
       6     License as published by the Free Software Foundation; either
       7     version 2.1 of the License, or (at your option) any later version.
       8  
       9     The GNU C Library is distributed in the hope that it will be useful,
      10     but WITHOUT ANY WARRANTY; without even the implied warranty of
      11     MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
      12     Lesser General Public License for more details.
      13  
      14     You should have received a copy of the GNU Lesser General Public
      15     License along with the GNU C Library; if not, see
      16     <https://www.gnu.org/licenses/>.  */
      17  
      18  #include <errno.h>
      19  #include <unistd.h>
      20  #include <stddef.h>
      21  
      22  /* Read NBYTES into BUF from FD.  Return the number read or -1.  */
      23  ssize_t
      24  __libc_read (int fd, void *buf, size_t nbytes)
      25  {
      26    if (nbytes == 0)
      27      return 0;
      28    if (fd < 0)
      29      {
      30        __set_errno (EBADF);
      31        return -1;
      32      }
      33    if (buf == NULL)
      34      {
      35        __set_errno (EINVAL);
      36        return -1;
      37      }
      38  
      39    __set_errno (ENOSYS);
      40    return -1;
      41  }
      42  libc_hidden_def (__libc_read)
      43  stub_warning (read)
      44  
      45  weak_alias (__libc_read, __read)
      46  libc_hidden_weak (__read)
      47  weak_alias (__libc_read, read)
      48  libc_hidden_weak (read)