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  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 4.15 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)