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FSEEKO(3)                  Linux Programmer's Manual                 FSEEKO(3)
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);
   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 defin-
       ing  _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 4.15 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/.
                                  2017-09-15                         FSEEKO(3)