getenv Gets the value of an environment variable &reftitle.description; stringgetenv stringvarname Gets the value of an environment variable. You can see a list of all the environmental variables by using phpinfo. You can find out what many of them mean by taking a look at the CGI specification, specifically the page on environmental variables. &reftitle.parameters; varname The variable name. &reftitle.returnvalues; Returns the value of the environment variable varname, or &false; on an error. &reftitle.examples; ]]> &reftitle.seealso; putenv apache_getenv Superglobals