# For foo.htm => foo.htm.tmp
opendir( HTMLSTORIES, "$html_dir") || die "HTML files do not exist: $!";
@FigureArray = grep{/\.htm$/} readdir ( HTMLSTORIES );
foreach $figfile (@FigureArray) {
    copy ($figfile, "$figfile.tmp") or die "Can not make temporary copy of file [$figfile]: $!";
}