FSEEKO
Section: Linux Programmer's Manual (3)
Updated: 2017-09-15
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NAME
fseeko, ftello - seek to or report file position
SYNOPSIS
#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
(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
|
CONFORMING TO
POSIX.1-2001, POSIX.1-2008, SUSv2.
SEE ALSO
fseek(3)
COLOPHON
This page is part of release 4.13 of the Linux
man-pages
project.
A description of the project,
information about reporting bugs,
and the latest version of this page,
can be found at
https://www.kernel.org/doc/man-pages/.
Index
- NAME
-
- SYNOPSIS
-
- DESCRIPTION
-
- RETURN VALUE
-
- ERRORS
-
- VERSIONS
-
- ATTRIBUTES
-
- CONFORMING TO
-
- SEE ALSO
-
- COLOPHON
-