以下は、各環境変数を取得して、ブラウザ画面に表示するサーバサイドプログラムのサンプルです。
#!/usr/bin/perl
$strServerName = $ENV{"SERVER_NAME"};
$strGatewayInterface = $ENV{"GATEWAY_INTERFACE"};
$strServerProtocol = $ENV{"SERVER_PROTOCOL"};
$strRequestMethod = $ENV{"REQUEST_METHOD"};
$strPathInfo = $ENV{"PATH_INFO"};
$strScriptName = $ENV{"SCRIPT_NAME"};
$strQueryString = $ENV{"QUERY_STRING"};
$strRemoteAddr = $ENV{"REMOTE_ADDR"};
$strRemoteHost = $ENV{"REMOTE_HOST"};
$numContentLength = $ENV{"CONTENT_LENGTH"};
$strHttpUserAgent = $ENV{"HTTP_USER_AGENT"};
$strHttpReferer = $ENV{"HTTP_REFERER"};
print "Content-Type: text/html\n\n";
print <<"EOF";
<html>
<body>
SERVER_NAME = ${strServerName}<br>
GATEWAY_INTERFACE = ${strGatewayInterface}<br>
SERVER_PROTOCOL = ${strServerProtocol}<br>
REQUEST_METHOD = ${strRequestMethod}<br>
PATH_INFO = ${strPathInfo}<br>
SCRIPT_NAME = ${strScriptName}<br>
QUERY_STRING = ${strQueryString}<br>
REMOTE_ADDR = ${strRemoteAddr}<br>
REMOTE_HOST = ${strRemoteHost}<br>
CONTENT_LENGTH = ${numContentLength}<br>
HTTP_USER_AGENT = ${strHttpUserAgent}<br>
HTTP_REFERER = ${strHttpReferer}<br>
</body>
</html>
EOF
$strServerName = $ENV{"SERVER_NAME"};
$strGatewayInterface = $ENV{"GATEWAY_INTERFACE"};
$strServerProtocol = $ENV{"SERVER_PROTOCOL"};
$strRequestMethod = $ENV{"REQUEST_METHOD"};
$strPathInfo = $ENV{"PATH_INFO"};
$strScriptName = $ENV{"SCRIPT_NAME"};
$strQueryString = $ENV{"QUERY_STRING"};
$strRemoteAddr = $ENV{"REMOTE_ADDR"};
$strRemoteHost = $ENV{"REMOTE_HOST"};
$numContentLength = $ENV{"CONTENT_LENGTH"};
$strHttpUserAgent = $ENV{"HTTP_USER_AGENT"};
$strHttpReferer = $ENV{"HTTP_REFERER"};
print "Content-Type: text/html\n\n";
print <<"EOF";
<html>
<body>
SERVER_NAME = ${strServerName}<br>
GATEWAY_INTERFACE = ${strGatewayInterface}<br>
SERVER_PROTOCOL = ${strServerProtocol}<br>
REQUEST_METHOD = ${strRequestMethod}<br>
PATH_INFO = ${strPathInfo}<br>
SCRIPT_NAME = ${strScriptName}<br>
QUERY_STRING = ${strQueryString}<br>
REMOTE_ADDR = ${strRemoteAddr}<br>
REMOTE_HOST = ${strRemoteHost}<br>
CONTENT_LENGTH = ${numContentLength}<br>
HTTP_USER_AGENT = ${strHttpUserAgent}<br>
HTTP_REFERER = ${strHttpReferer}<br>
</body>
</html>
EOF