Name

RewriteCond

Synopsis

RewriteCond TestString 
                     CondPattern
Server config, virtual host, directory

One or more RewriteCond directives can precede a RewriteRule directive to define conditions under which it is to be applied. CondPattern is a regular expression matched against the value retrieved for TestString, which contains server variables of the form %{ NAME_OF_VARIABLE }, where NAME_OF_VARIABLE can be one of the following list:

API_VERSION	PATH_INFO	SERVER_PROTOCOL
AUTH_TYPE	QUERY_STRING	SERVER_SOFTWARE
DOCUMENT_ROOT	REMOTE_ADDR	THE_REQUEST
ENV:any_environment_variable	REMOTE_HOST	TIME
HTTP_ACCEPT	REMOTE_USER	TIME_DAY
HTTP_COOKIE	REMOTE_IDENT	TIME_HOUR
HTTP_FORWARDED	REQUEST_FILENAME	TIME_MIN
HTTP_HOST	REQUEST_METHOD	TIME_MON
HTTP_PROXY_CONNECTION	REQUEST_URI	TIME_SEC
HTTP_REFERER	SCRIPT_FILENAME	TIME_WDAY
HTTP_USER_AGENT	SERVER_ADMIN	TIME_YEAR
HTTP:any_HTTP_header	SERVER_NAME
IS_SUBREQ	SERVER_PORT

These variables all correspond to the similarly named HTTP MIME headers, C variables of the Apache server, or the current time. If the regular expression does not match, the RewriteRule following it does not apply.