75 lines
1.7 KiB
C
75 lines
1.7 KiB
C
/*
|
|
FUNCTION
|
|
<<fgetpos64>>---record position in a large stream or file
|
|
|
|
INDEX
|
|
fgetpos64
|
|
INDEX
|
|
_fgetpos64_r
|
|
|
|
SYNOPSIS
|
|
#include <stdio.h>
|
|
int fgetpos64(FILE *<[fp]>, _fpos64_t *<[pos]>);
|
|
int _fgetpos64_r(struct _reent *<[ptr]>, FILE *<[fp]>,
|
|
_fpos64_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 <<fgetpos64>> to report on the current position for a file
|
|
identified by <[fp]> that was opened by <<fopen64>>; <<fgetpos>> will write
|
|
a value representing that position at <<*<[pos]>>>. Later, you can
|
|
use this value with <<fsetpos64>> to return the file to this
|
|
position.
|
|
|
|
In the current implementation, <<fgetpos64>> simply uses a character
|
|
count to represent the file position; this is the same number that
|
|
would be returned by <<ftello64>>.
|
|
|
|
RETURNS
|
|
<<fgetpos64>> returns <<0>> when successful. If <<fgetpos64>> fails, the
|
|
result is <<1>>. Failure occurs on streams that do not support
|
|
positioning or streams not opened via <<fopen64>>; the global <<errno>>
|
|
indicates these conditions with the value <<ESPIPE>>.
|
|
|
|
PORTABILITY
|
|
<<fgetpos64>> is a glibc extension.
|
|
|
|
No supporting OS subroutines are required.
|
|
*/
|
|
|
|
#include <stdio.h>
|
|
|
|
#ifdef __LARGE64_FILES
|
|
|
|
int
|
|
_DEFUN (_fgetpos64_r, (ptr, fp, pos),
|
|
struct _reent * ptr _AND
|
|
FILE * fp _AND
|
|
_fpos64_t * pos)
|
|
{
|
|
*pos = (_fpos64_t)_ftello64_r (ptr, fp);
|
|
|
|
if (*pos != -1)
|
|
{
|
|
return 0;
|
|
}
|
|
return 1;
|
|
}
|
|
|
|
#ifndef _REENT_ONLY
|
|
|
|
int
|
|
_DEFUN (fgetpos64, (fp, pos),
|
|
FILE * fp _AND
|
|
_fpos64_t * pos)
|
|
{
|
|
return _fgetpos64_r (_REENT, fp, pos);
|
|
}
|
|
|
|
#endif /* !_REENT_ONLY */
|
|
|
|
#endif /* __LARGE64_FILES */
|