1 /* An ftell() function that works around platform bugs. 2 Copyright (C) 2007-2021 Free Software Foundation, Inc. 3 4 This file is free software: you can redistribute it and/or modify 5 it under the terms of the GNU Lesser General Public License as 6 published by the Free Software Foundation; either version 2.1 of the 7 License, or (at your option) any later version. 8 9 This file 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 12 GNU Lesser General Public License for more details. 13 14 You should have received a copy of the GNU Lesser General Public License 15 along with this program. If not, see <https://www.gnu.org/licenses/>. */ 16 17 #include <config.h> 18 19 /* Specification. */ 20 #include <stdio.h> 21 22 #include <errno.h> 23 #include <limits.h> 24 25 long 26 ftell (FILE *fp) /* */ 27 { 28 /* Use the replacement ftello function with all its workarounds. */ 29 off_t offset = ftello (fp); 30 if (LONG_MIN <= offset && offset <= LONG_MAX) 31 return /* (long) */ offset; 32 else 33 { 34 errno = EOVERFLOW; 35 return -1; 36 } 37 }