.help imopen Sep86 imfort .ih NAME imopen -- open an existing image .ih SYNOPSIS .nf subroutine imopen (image, acmode, im, ier) character*(*) image #I host image to be opened integer acmode #I access mode integer im #O receives image descriptor integer ier #O status code .fi .ih DESCRIPTION The \fIimopen\fR procedure is used to open an existing image for either read only access (\fIacmode\fR=1) or read write access (\fIacmode\fR=3). The image name must be the host system filename of the image, although the extension may be omitted if desired. If the image open is successful an image descriptor is returned in \fIim\fR. .ih RETURN VALUE A nonzero status code is returned if the image does not exist or cannot be opened with the indicated access mode. .nf IE_OPEN: cannot open image IE_NOTIMH: attempt to access a non-image file as an image IE_OPNPIX: cannot open pixel file .fi .ih SEE ALSO imclos, imcrea, imopnc, imdele, imrnam .endhelp