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/* An ftello() function that works around platform bugs. 
   Copyright (C) 2007, 2009-2013 Free Software Foundation, Inc. 
 
   This program is free software: you can redistribute it and/or modify 
   it under the terms of the GNU General Public License as published by 
   the Free Software Foundation; either version 3 of the License, or 
   (at your option) any later version. 
 
   This program is distributed in the hope that it will be useful, 
   but WITHOUT ANY WARRANTY; without even the implied warranty of 
   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the 
   GNU General Public License for more details. 
 
   You should have received a copy of the GNU General Public License 
   along with this program.  If not, see <http://www.gnu.org/licenses/>.  */ 
 
#include <config.h> 
 
/* Specification.  */ 
#include <stdio.h> 
 
/* Get lseek.  */ 
#include <unistd.h> 
 
#include "stdio-impl.h" 
 
off_t 
ftello (FILE *fp) 
#undef ftello 
#if !HAVE_FTELLO 
# undef ftell 
# define ftello ftell 
#endif 
#if _GL_WINDOWS_64_BIT_OFF_T 
# undef ftello 
# if HAVE__FTELLI64 /* msvc, mingw64 */ 
#  define ftello _ftelli64 
# else /* mingw */ 
#  define ftello ftello64 
# endif 
#endif 
{ 
#if LSEEK_PIPE_BROKEN 
  /* mingw gives bogus answers rather than failure on non-seekable files.  */ 
  if (lseek (fileno (fp), 0, SEEK_CUR) == -1) 
    return -1; 
#endif 
 
#if FTELLO_BROKEN_AFTER_SWITCHING_FROM_READ_TO_WRITE /* Solaris */ 
  /* The Solaris stdio leaves the _IOREAD flag set after reading from a file 
     reaches EOF and the program then starts writing to the file.  ftello 
     gets confused by this.  */ 
  if (fp_->_flag & _IOWRT) 
    { 
      off_t pos; 
 
      /* Call ftello nevertheless, for the side effects that it does on fp.  */ 
      ftello (fp); 
 
      /* Compute the file position ourselves.  */ 
      pos = lseek (fileno (fp), (off_t) 0, SEEK_CUR); 
      if (pos >= 0) 
        { 
          if ((fp_->_flag & _IONBF) == 0 && fp_->_base != NULL) 
            pos += fp_->_ptr - fp_->_base; 
        } 
      return pos; 
    } 
#endif 
 
#if defined __SL64 && defined __SCLE /* Cygwin */ 
  if ((fp->_flags & __SL64) == 0) 
    { 
      /* Cygwin 1.5.0 through 1.5.24 failed to open stdin in 64-bit 
         mode; but has an ftello that requires 64-bit mode.  */ 
      FILE *tmp = fopen ("/dev/null", "r"); 
      if (!tmp) 
        return -1; 
      fp->_flags |= __SL64; 
      fp->_seek64 = tmp->_seek64; 
      fclose (tmp); 
    } 
#endif 
  return ftello (fp); 
}