APPSRV_HEADER

The DATA step function used to add or modify a header

Syntax
Arguments
Details
Examples

Syntax

OLD-HEADER = APPSRV_HEADER(Header Name,Header Value);

Arguments

Header name

The name of the header to set or reset.

Header Value

The new value for the header.

Details

The APPSRV_HEADER function enables automatic header generation. You can add a header to the default list or modify an existing header from the list. When you modify the value of an existing header, the old value becomes the return value of the function.

The automatic HTTP header generation feature recognizes Output Delivery System (ODS) output types and generates appropriate default content-type headers. If no content type is specified with APPSRV_HEADER, ODS is not used and no HTTP header is written to _WEBOUT, a default Content-type: text/html header is generated.

Examples

No calls to appsrv_header 

Content-type: text/html

/* add expires header */
rc = appsrv_header('Expires','Thu, 
   18 Nov 1999 12:23:34 GMT'); 

Content-type: text/html 
Expires: Thu, 18 Nov 1999 12:23:34 GMT

/* add expires header */
rc = appsrv_header('Expires','Thu, 
   18 Nov 1999 12:23:34 GMT');
/* add pragma header*/
rc = appsrv_header('Cache-control',
   'no-cache');

Content-type: text/html
Expires: Thu, 18 Nov 1999 12:23:34 GMT 
Cache-control: no-cache

/* add expires header */
rc = appsrv_header('Expires','Thu, 
   18 Nov 1999 12:23:34 GMT');
/* add pragma header*/
rc = appsrv_header('Cache-control',
   'no-cache');
...
/* remove expires header, rc 
   contains old value */
rc = appsrv_header('Expires','');

Content-type: text/html
Cache-control: no-cache

Disabling Automatic Header Generation

To completely disable Automatic Header Generation for a request, call the APPSRVSET DATA step function, as so:

   data _NULL_;
      rc = appsrvset("automatic headers", 0);
   run;

Copyright © 2007 by SAS Institute Inc., Cary, NC, USA. All rights reserved.