squid(8) on Linux
The text f640ba52140c, as Debian 4.0 (Etch) shipped it.
proxy caching server
Flags it lists
-
-C -
-D -
-F -
-N -
-O -
-R -
-X -
-Y -
-d -
-f -
-h -
-i -
-l -
-n -
-r -
-s -
-u -
-v -
-z