im_iocheck(3) im_iocheck(3)
NAME
im_incheck, im_outcheck, im_iocheck - checks image descriptors for WIO
SYNOPSIS
#include <vips.h>
int im_incheck( in )
IMAGE *in;
int im_outcheck( out )
IMAGE *out;
int im_iocheck( in, out)
IMAGE *in, *out;
DESCRIPTION
im_incheck(3) checks that an image descriptor is suitable for WIO input
(ie. all of its pels can be found from im->data). If possible, it
transforms the descriptor to make WIO input ok using the following
rules:
IM_PARTIAL: the descriptor is magically turned into an IM_SETBUF
descriptor. Memory is allocated and the image generated into that. The
old partial callbacks are closed down, and the descriptor reformed as a
IM_SETBUF.
IM_OPENOUT: if the descriptor has been written to, it is automatically
`rewound,` that is, it is closed and reopened as an IM_MMAPIN descrip-
tor.
IM_SETBUF: just checks that the descriptor has been written to.
See the manual page for im_setupout(3) for a skeleton program.
im_outcheck(3) checks that a descriptor is suitable for WIO output with
im_writeline(3). If it sees an IM_PARTIAL image, it turns it magically
into an IM_SETBUF image.
im_iocheck(3) simply calls in_incheck(3) for image in and
im_outcheck(3) for image out.
RETURN VALUE
All functions returns 0 on success and -1 on error.
SEE ALSO
im_open(3), im_cp_desc(3), im_setupout(3), im_makerw(3).
COPYRIGHT
National Gallery
AUTHOR
J. Cupitt - 23/7/93
11 April 1990 im_iocheck(3)
im_iocheck 7.14.5 - Generated Sun Sep 7 15:11:42 CDT 2008