fgetpos[record position in a stream or file]

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fgetpos
[record position in a stream or file]

SYNOPSIS
#include <stdio.h>
int fgetpos(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 position 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.

COMPLIANCE
fgetpos is required by ANSI C, but the meaning of the value it records is not specified beyond requiring that it be acceptable 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.