HIDDEN input fields in forms. Only a limited amount of
data can be stored in this way, but it is quick and easy.More sophisticated methods might rely on Netscape Cookies, or storing the name of a temporary file in a hidden variable, etc.
The following routines pack and restore pairs of points into a string
of the form x1 z y1 q x2 z y2 q .... They use the global
variables $history for the string and
@hx,@hy for the arrays of points.
sub pack_history (
$hl = $#hx;
if ($hl > 10) {$hl = 10;} # limit to 10 pairs
$history = "";
for $i (0..$hl) {
$history .= $hx[$i]."z".$hy[$i]."q";
}
}
sub expand_history (
@pairs = split('q',$history);
$i = $#pairs;
foreach $i (0..$#pairs) {
($hx[$i], $hy[$i]) = split('z',$pairs[$i]);
}
}
# Scan for old files and erase them.
opendir(WORKDIR, $WORKDIR);
$old = time() - 600; # "Old" files haven't been touched in 600 sec=10min
foreach $_ (readdir(WORKDIR)) {
if(/^.+$gifsuffix$/ || /^.+$pssuffix$/ ) { # any file with suffixes
$thisfile=$WORKDIR . "/" . $_;
@stat = stat($thisfile); # stat[8]=mtime; stat[9]=ctime
unlink($thisfile) if($stat[8] < $old && $stat[9] < $old);
}
}
close(WORKDIR);