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# Copyright(c) 1986 Association of Universities for Research in Astronomy Inc.
include <imhdr.h>
include "imfort.h"
# IMGL2S -- Get a line from an image of type short. It is illegal to reference
# out of bounds.
procedure imgl2s (im, buf, lineno, ier)
pointer im # image descriptor
short buf[ARB] # user data buffer
int lineno # line number
int ier
long offset
int nchars, npix
int bfread()
begin
# Verify in bounds.
if (lineno < 1 || lineno > IM_LEN(im,2)) {
ier = IE_YOOB
call im_seterrim (ier, im)
return
}
# Verify that the image is of type short.
if (IM_PIXTYPE(im) != TY_SHORT) {
ier = IE_NOTSHORT
call im_seterrim (ier, im)
return
}
npix = IM_LEN(im,1)
nchars = npix * IM_SZPIXEL(im)
# Compute offset into pixel file.
offset = IM_PIXOFF(im) + (lineno-1) * IM_LINESIZE(im)
# Read one line of data.
if (nchars != bfread (IM_PIXFP(im), buf, nchars, offset)) {
ier = IE_RDPIX
call im_seterrim (ier, im)
return
}
# Swap bytes if necessary.
call imswap (im, buf, nchars)
ier = OK
end
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