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/*
FUNCTION
<<fsetpos>>---restore position of a stream or file
INDEX
fsetpos
ANSI_SYNOPSIS
#include <stdio.h>
int fsetpos(FILE *<[fp]>, const fpos_t *<[pos]>);
TRAD_SYNOPSIS
#include <stdio.h>
int fsetpos(<[fp]>, <[pos]>)
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 <<fsetpos>> to return the file identified by <[fp]> to a previous
position <<*<[pos]>>> (after first recording it with <<fgetpos>>).
See <<fseek>> for a similar facility.
RETURNS
<<fgetpos>> returns <<0>> when successful. If <<fgetpos>> fails, the
result is <<1>>. The reason for failure is indicated in <<errno>>:
either <<ESPIPE>> (the stream identified by <[fp]> doesn't support
repositioning) or <<EINVAL>> (invalid file position).
PORTABILITY
ANSI C requires <<fsetpos>>, but does not specify the nature of
<<*<[pos]>>> beyond identifying it as written by <<fgetpos>>.
Supporting OS subroutines required: <<close>>, <<fstat>>, <<isatty>>,
<<lseek>>, <<read>>, <<sbrk>>, <<write>>.
*/
#include <stdio.h>
int
_DEFUN (fsetpos, (iop, pos),
FILE * iop _AND
_CONST fpos_t * pos)
{
int x = fseek (iop, *pos, SEEK_SET);
if (x != 0)
return 1;
return 0;
}
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