FGETPOS(3) NEWLIB FGETPOS(3)NAME
4.11 `fgetpos'--record position in a stream or file
SYNOPSIS
#include <stdio.h>
int fgetpos(FILE *FP, fpos_t *POS);
int _fgetpos_r(struct _reent *PTR, FILE *FP, fpos_t *POS);
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.
You can use `fgetpos' to report on the current position for a file
identified by FP; `fgetpos' will write a value representing that posi‐
tion at `*POS'. Later, you can use this value with `fsetpos' to return
the file to this position.
In the current implementation, `fgetpos' simply uses a character
count to represent the file position; this is the same number that
would be returned by `ftell'.
RETURNS
`fgetpos' returns `0' when successful. If `fgetpos' fails, the result
is `1'. Failure occurs on streams that do not support positioning; the
global `errno' indicates this condition with the value `ESPIPE'.
PORTABILITY
`fgetpos' is required by the ANSI C standard, but the meaning of the
value it records is not specified beyond requiring that it be accept‐
able as an argument to `fsetpos'. In particular, other conforming C
implementations may return a different result from `ftell' than what
`fgetpos' writes at `*POS'.
No supporting OS subroutines are required.
SEE ALSOfgetpos 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 FGETPOS(3)
