Exporting Environment Variables

The following table from the sample configuration file lists some standard CGI environment variables. However, you can pass any variables that your Web server supports. (For more information about environment variables, see the CGI area at the World Wide Web Consortium Web site at www.w3.org.)

Note: These SAS macro variable names are suggestions only; you do not need to use these exact names.

Environment variables	SAS macro variable	Description
GATEWAY_INTERFACE	_GATEWAY	Version of the Common Gateway Interface (CGI) that the Web server uses.
SERVER_NAME	_SRVNAME	Web server's DNS (host) name or IP address.
SERVER_SOFTWARE	_SRVSOFT	Web server software name and version.
SERVER_PROTOCOL	_SRVPROT	Name and revision of the HTTP information protocol transmitting the client request.
SERVER_PORT	_SRVPORT	Web server port number.
REQUEST_METHOD	_REQMETH	Method with which the information request was issued, for example, GET or POST. This corresponds with the <FORM...METHOD=GET\|POST> statement in the HTML form.
PATH_INFO	_PATHINF	Extra path information after the script passed to a CGI program.
PATH_TRANSLATED	_PATHTRN	Local filename of PATH_INFO.
SCRIPT_NAME	_SCRIPT	Virtual path of the script being executed. In this case, a duplicate of _URL, another macro variable passed to the Application Dispatcher program.
DOCUMENT_ROOT	_DOCROOT	Directory from which Web documents are served. This variable is unreliable.
QUERY_STRING	_QRYSTR	Query information passed to the program. It is appended to the URL with a question mark (?). In this case, it is an unparsed version of the user macro parameters. Set only with GET.
REMOTE_HOST	_RMTHOST	User's DNS (remote host) name, if known.
REMOTE_ADDR	_RMTADDR	User's IP address.
AUTH_TYPE	_AUTHTYP	Authentication method used to validate a user, usually Basic.
REMOTE_USER	_RMTUSER	User name, if authenticated.
REMOTE_IDENT	_RMTID	Identification of user making request. RFC931 ID, if supported.
CONTENT_TYPE	_CONTTYP	The Internet media type (MIME type) of the query data. Set only with POST.
CONTENT_LENGTH	_CONTLEN	Length of the data (in bytes or number of characters) passed to the CGI program. Set only with POST.
HTTP_FROM	_HTFROM	E-mail address of the user making the request (unreliable).
HTTP_ACCEPT	_HTACPT	Internet media (MIME) types that the client can accept. However, you might find using the HTTP_USER_AGENT variable more reliable than HTTP_ACCEPT.
HTTP_COOKIE	_HTCOOK	Cookies. See also the Set-Cookie header line.
HTTP_USER_AGENT	_HTUA	Web browser name.
HTTP_REFERER	_HTREFER	If known, the URL of the document that the client points to before accessing the CGI program.

The Web server makes essential information available to CGI programs as environment variables. You can pass some or all of this information on to your Application Dispatcher programs by using the Export directive. The syntax is

Export <environment-variable> <SAS variable name>

The Export directive instructs the Application Broker to retrieve the contents of the specified environment variable and make it available to Application Dispatcher programs in the specified SAS macro variable or SCL list item.

The sample configuration file includes several Export directives. You can activate a directive by changing the information to match your site and removing the # that appears at the left of the export line.

Some Export directives are activated by default. Export REMOTE_HOST _RMTHOST is one. These directives are not preceded by a # in the default configuration file.

If you omit the SAS name, the name of the environment variable is used as the SAS macro name.

If the value of the environment variable is greater than your field width (as set in _FLDWDTH), then the variable divides like any field into multiple variables. You can avoid this by using SAS variable names with a leading underscore, such as _RMTHOST. Application Dispatcher variables that begin with an underscore are not divided according to _FLDWDTH. These variables are truncated at 32767 characters.