fseeko (3)
Leading comments
Copyright 2001 Andries Brouwer <aeb@cwi.nl>. %%%LICENSE_START(VERBATIM) Permission is granted to make and distribute verbatim copies of this manual provided the copyright notice and this permission notice are preserved on all copies. Permission is granted to copy and distribute modified versions of this manual under the conditions for verbatim copying, provided that the entire resulting derived work is distributed under the terms of a permission notice identical to this one. Since the Linu...
NAME
fseeko, ftello - seek to or report file positionSYNOPSIS
#include <stdio.h> int fseeko(FILE *stream, off_t offset, int whence); off_t ftello(FILE *stream); .fi Feature Test Macro Requirements for glibc (see feature_test_macros(7)): fseeko(), ftello():
- _FILE_OFFSET_BITS == 64 ||
_POSIX_C_SOURCE >= 200112L || _XOPEN_SOURCE >= 600
(defining the obsolete _LARGEFILE_SOURCE macro also works)
DESCRIPTION
The fseeko() and ftello() functions are identical to fseek(3) and ftell(3) (see fseek(3)), respectively, except that the offset argument of fseeko() and the return value of ftello() is of type off_t instead of long.On some architectures, both off_t and long are 32-bit types, but defining _FILE_OFFSET_BITS with the value 64 (before including any header files) will turn off_t into a 64-bit type.
RETURN VALUE
On successful completion, fseeko() returns 0, while ftello() returns the current offset. Otherwise, -1 is returned and errno is set to indicate the error.ERRORS
See the ERRORS in fseek(3).VERSIONS
These functions are available under glibc since version 2.1.ATTRIBUTES
For an explanation of the terms used in this section, see attributes(7).| Interface | Attribute | Value |
| fseeko(), ftello() | Thread safety | MT-Safe |