mirror of https://github.com/mkerrisk/man-pages
119 lines
2.7 KiB
Groff
119 lines
2.7 KiB
Groff
.\" 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 Linux kernel and libraries are constantly changing, this
|
|
.\" manual page may be incorrect or out-of-date. The author(s) assume no
|
|
.\" responsibility for errors or omissions, or for damages resulting from
|
|
.\" the use of the information contained herein. The author(s) may not
|
|
.\" have taken the same level of care in the production of this manual,
|
|
.\" which is licensed free of charge, as they might when working
|
|
.\" professionally.
|
|
.\"
|
|
.\" Formatted or processed versions of this manual, if unaccompanied by
|
|
.\" the source, must acknowledge the copyright and authors of this work.
|
|
.\" %%%LICENSE_END
|
|
.\"
|
|
.TH FSEEKO 3 2016-03-15 "" "Linux Programmer's Manual"
|
|
.SH NAME
|
|
fseeko, ftello \- seek to or report file position
|
|
.SH SYNOPSIS
|
|
.nf
|
|
.B #include <stdio.h>
|
|
.PP
|
|
.BI "int fseeko(FILE *" stream ", off_t " offset ", int " whence );
|
|
.PP
|
|
.BI "off_t ftello(FILE *" stream );
|
|
.BI
|
|
.fi
|
|
.PP
|
|
.in -4n
|
|
Feature Test Macro Requirements for glibc (see
|
|
.BR feature_test_macros (7)):
|
|
.in
|
|
.PP
|
|
.BR fseeko (),
|
|
.BR ftello ():
|
|
.br
|
|
.RS 4
|
|
.ad l
|
|
_FILE_OFFSET_BITS\ ==\ 64 || _POSIX_C_SOURCE\ >=\ 200112L
|
|
.br
|
|
(defining the obsolete _LARGEFILE_SOURCE macro also works)
|
|
.RE
|
|
.ad
|
|
.SH DESCRIPTION
|
|
The
|
|
.BR fseeko ()
|
|
and
|
|
.BR ftello ()
|
|
functions are identical to
|
|
.BR fseek (3)
|
|
and
|
|
.BR ftell (3)
|
|
(see
|
|
.BR fseek (3)),
|
|
respectively, except that the
|
|
.I offset
|
|
argument of
|
|
.BR fseeko ()
|
|
and the return value of
|
|
.BR ftello ()
|
|
is of type
|
|
.I off_t
|
|
instead of
|
|
.IR long .
|
|
.PP
|
|
On some architectures, both
|
|
.IR off_t
|
|
and
|
|
.I long
|
|
are 32-bit types, but defining
|
|
.BR _FILE_OFFSET_BITS
|
|
with the value 64 (before including
|
|
.I any
|
|
header files)
|
|
will turn
|
|
.I off_t
|
|
into a 64-bit type.
|
|
.SH RETURN VALUE
|
|
On successful completion,
|
|
.BR fseeko ()
|
|
returns 0, while
|
|
.BR ftello ()
|
|
returns the current offset.
|
|
Otherwise, \-1 is returned and
|
|
.I errno
|
|
is set to indicate the error.
|
|
.SH ERRORS
|
|
See the ERRORS in
|
|
.BR fseek (3).
|
|
.SH VERSIONS
|
|
These functions are available under glibc since version 2.1.
|
|
.SH ATTRIBUTES
|
|
For an explanation of the terms used in this section, see
|
|
.BR attributes (7).
|
|
.TS
|
|
allbox;
|
|
lbw18 lb lb
|
|
l l l.
|
|
Interface Attribute Value
|
|
T{
|
|
.BR fseeko (),
|
|
.BR ftello ()
|
|
T} Thread safety MT-Safe
|
|
.TE
|
|
.sp 1
|
|
.SH CONFORMING TO
|
|
POSIX.1-2001, POSIX.1-2008, SUSv2.
|
|
.SH SEE ALSO
|
|
.BR fseek (3)
|