1 files changed, 40 insertions, 0 deletions
diff --git a/gnu/usr.bin/perl/lib/cacheout.pl b/gnu/usr.bin/perl/lib/cacheout.pl
new file mode 100644
index 0000000..513c25b
--- /dev/null
+++ b/gnu/usr.bin/perl/lib/cacheout.pl
@@ -0,0 +1,40 @@
+# Open in their package.
+
+sub cacheout'open {
+    open($_[0], $_[1]);
+}
+
+# But only this sub name is visible to them.
+
+sub cacheout {
+    package cacheout;
+
+    ($file) = @_;
+    if (!$isopen{$file}) {
+	if (++$numopen > $maxopen) {
+	    local(@lru) = sort {$isopen{$a} <=> $isopen{$b};} keys(%isopen);
+	    splice(@lru, $maxopen / 3);
+	    $numopen -= @lru;
+	    for (@lru) { close $_; delete $isopen{$_}; }
+	}
+	&open($file, ($saw{$file}++ ? '>>' : '>') . $file)
+	    || die "Can't create $file: $!\n";
+    }
+    $isopen{$file} = ++$seq;
+}
+
+package cacheout;
+
+$seq = 0;
+$numopen = 0;
+
+if (open(PARAM,'/usr/include/sys/param.h')) {
+    local($.);
+    while (<PARAM>) {
+	$maxopen = $1 - 4 if /^\s*#\s*define\s+NOFILE\s+(\d+)/;
+    }
+    close PARAM;
+}
+$maxopen = 16 unless $maxopen;
+
+1;