This section lists the CGI 1.1 variables that some web servers create when a CGI script is called.
The CGI variables that are available for your use vary with the web server and configuration. Some of the following variables may not be available.
CGI.AUTH_TYPE
CGI.CONTENT_LENGTH CGI.CONTENT_TYPE CGI.PATH_INFO CGI.PATH_TRANSLATED CGI.QUERY_STRING CGI.REMOTE_ADDR CGI.REMOTE_HOST CGI.REMOTE_USER CGI.REQUEST_METHOD CGI.SCRIPT_NAME
CGI.GATEWAY_INTERFACE
CGI.SERVER_NAME CGI.SERVER_PORT CGI.SERVER_PROTOCOL CGI.SERVER_SOFTWARE
CGI.CERT_ISSUER
CGI.CERT_SUBJECT CGI.CLIENT_CERT_ENCODED CGI.HTTP_ACCEPT CGI.HTTP_IF_MODIFIED_SINCE CGI.HTTP_USER_AGENT
The CERT_ISSUER, CERT_SUBJECT, CLIENT_CERT_ENCODED variables are available only when you use client certificates.