Mod rewrite environment variables

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List of variables available in mod_rewrite:

API_VERSION
AUTH_TYPE
CONTENT_LENGTH
CONTENT_TYPE
DOCUMENT_ROOT
GATEWAY_INTERFACE
HTTPS
HTTP_ACCEPT
HTTP_ACCEPT_CHARSET
HTTP_ACCEPT_ENCODING
HTTP_ACCEPT_LANGUAGE
HTTP_CACHE_CONTROL
HTTP_CONNECTION
HTTP_COOKIE
HTTP_FORWARDED
HTTP_HOST
HTTP_KEEP_ALIVE
HTTP_PROXY_CONNECTION
HTTP_REFERER
HTTP_USER_AGENT
IS_SUBREQ
ORIG_PATH_INFO
ORIG_PATH_TRANSLATED
ORIG_SCRIPT_FILENAME
ORIG_SCRIPT_NAME
PATH
PATH_INFO
PHP_SELF
QUERY_STRING
REDIRECT_QUERY_STRING
REDIRECT_REMOTE_USER
REDIRECT_STATUS
REDIRECT_URL
REMOTE_ADDR
REMOTE_HOST
REMOTE_IDENT
REMOTE_PORT
REMOTE_USER
REQUEST_FILENAME
REQUEST_METHOD
REQUEST_TIME
REQUEST_URI
SCRIPT_FILENAME
SCRIPT_GROUP
SCRIPT_NAME
SCRIPT_URI
SCRIPT_URL
SCRIPT_USER
SERVER_ADDR
SERVER_ADMIN
SERVER_NAME
SERVER_PORT
SERVER_PROTOCOL
SERVER_SIGNATURE
SERVER_SOFTWARE
SSL_CIPHER
SSL_CIPHER_ALGKEYSIZE
SSL_CIPHER_EXPORT
SSL_CIPHER_USEKEYSIZE
SSL_CLIENT_VERIFY
SSL_PROTOCOL
SSL_SERVER_A_KEY
SSL_SERVER_A_SIG
SSL_SERVER_CERT
SSL_SERVER_I_DN
SSL_SERVER_I_DN_C
SSL_SERVER_I_DN_CN
SSL_SERVER_I_DN_L
SSL_SERVER_I_DN_O
SSL_SERVER_I_DN_OU
SSL_SERVER_I_DN_ST
SSL_SERVER_M_SERIAL
SSL_SERVER_M_VERSION
SSL_SERVER_S_DN
SSL_SERVER_S_DN_CN
SSL_SERVER_S_DN_O
SSL_SERVER_S_DN_OU
SSL_SERVER_V_END
SSL_SERVER_V_START
SSL_SESSION_ID
SSL_VERSION_INTERFACE
SSL_VERSION_LIBRARY
THE_REQUEST
TIME
TIME_DAY
TIME_HOUR
TIME_MIN
TIME_MON
TIME_SEC
TIME_WDAY
TIME_YEAR
TZ
UNIQUE_ID