( resource psdoc )
Mainly frees memory used by the document. Also closes a file, if it was not
closed before with ps_close(). You should in any case
close the file with ps_close() before, because
ps_close() not just closes the file but also outputs a
last line containing the PostScript comment with the number of pages in the
document. Without this comment, a PostScript viewer may not show the number
of pages properly.