The Apache Web Server version 2.2.12 released today, including the following nugget of joy:
‘discardpathinfo|DPI’ (discard PATH_INFO)
In per-directory context, the URI each RewriteRule compares against is the concatenation of the current values of the URI and PATH_INFO.
The current URI can be the initial URI as requested by the client, the result of a previous round of mod_rewrite processing, or the result of a prior rule in the current round of mod_rewrite processing.
In contrast, the PATH_INFO that is appended to the URI before each rule reflects only the value of PATH_INFO before this round of mod_rewrite processing. As a consequence, if large portions of the URI are matched and copied into a substitution in multiple RewriteRule directives, without regard for which parts of the URI came from the current PATH_INFO, the final URI may have multiple copies of PATH_INFO appended to it.
Use this flag on any substitution where the PATH_INFO that resulted from the previous mapping of this request to the filesystem is not of interest. This flag permanently forgets the PATH_INFO established before this round of mod_rewrite processing began. PATH_INFO will not be recalculated until the current round of mod_rewrite processing completes. Subsequent rules during this round of processing will see only the direct result of substitutions, without any PATH_INFO appended.
It might also be handy, some day, to have a [DQS] flag that discards the query string explicitly, rather than having to do silly tricks to make it disappear.