FTELLO64(3) NEWLIB FTELLO64(3)NAME
5.3 `ftello64'--return position in a stream or file
SYNOPSIS
#include <stdio.h>
_off64_t ftello64(FILE *FP);
_off64_t _ftello64_r(struct _reent *PTR, FILE *FP);
DESCRIPTION
Objects of type `FILE' can have a "position" that records how much of
the file your program has already read. Many of the `stdio' functions
depend on this position, and many change it as a side effect.
The result of `ftello64' is the current position for a large file
identified by FP. If you record this result, you can later use it with
`fseeko64' to return the file to this position. The difference between
`ftello' and `ftello64' is that `ftello' returns `off_t' and `ftello64'
is designed to work for large files (>2GB) and returns `_off64_t'.
In the current implementation, `ftello64' simply uses a character
count to represent the file position; this is the same number that
would be recorded by `fgetpos64'.
The function exists only if the __LARGE64_FILES flag is defined. An
error occurs if the FP was not opened via `fopen64'.
RETURNS
`ftello64' returns the file position, if possible. If it cannot do
this, it returns `-1'. Failure occurs on streams that do not support
positioning or not opened via `fopen64'; the global `errno' indicates
this condition with the value `ESPIPE'.
PORTABILITY
`ftello64' is a glibc extension.
No supporting OS subroutines are required.
SEE ALSO
ftello64 is part of the library. The full documentation for is main‐
tained as a Texinfo manual. If info and are properly installed at your
site, the command
info
will give you access to the complete manual.
NEWLIB April 2010 FTELLO64(3)