$Web_Expire
<section begin="desc" />Set expiration date/time of Web response<section end="desc" />
$Web_Expire sets the expiration date and time for the Web Server response entity being returned by the application. Using $WEB_EXPIRE, you can control how long a browser caches an entity returned by your application.
Syntax
<section begin="syntax" /> %RC = $Web_Expire( exp_time ) <section end="syntax" />
$Web_Expire requires one argument and returns a numeric status code. It is also callable (see Calling Sirius Mods $functions).
| exp_time | A date/time expressed in seconds since 12 AM on January 1, 1900. You can use the $WEB_DATENS function to get the current date in this format, and manipulate it using standard User Language expressions. |
|---|
| Code | Meaning |
|---|---|
| 0 | Completed successfully |
| -1 | Not a web thread |
| -4 | Invalid datetime value |
$WEB_EXPIRE return codes
Use $Web_Expire to control how long a browser caches an entity returned by your application.
* Get current date in binary %X = $WEB_DATENS * Add one week to the current date %X = %X + 7*24*60*60 * Ensure browser doesn't cache returned data * longer than one week %RC = $Web_Expire( %X ) * Changed my mind, only cache URL for 1 hour. * The previous $Web_Expire call is forgotten. %X = %X - (7*24-1)*60*60 %RC = $Web_Expire( %X )
In the above example, $Web_Expire is called to set the expiration date for the response entity. A second $Web_Expire demonstrates that you can override the $Web_Expire value any time you wish.
See also $Web_Last_Modified and .