$Web_Restore_List or $Web_Rest_List
Restore saved $list
$Web_Restore_List restores a Sirius $list that had been saved in the same or an earlier session (with $Web_Save_List) to another $list. $Web_Rest_List is a synonym for $Web_Restore_List.
$Web_Restore_List is a callable $function.
$Web_Restore_List accepts three arguments, the first two required, and it returns a numeric return code indicating the nature of any error.
Syntax
%rc = $Web_Restore_List( listid, id, opts )
Syntax terms
%rc | A numeric status code. | ||||
---|---|---|---|---|---|
listid | The identifier of the $list to receive the saved $list. This identifier is probably the output from a $ListNew call. This argument is required. The current contents of the this $list are replaced by the contents of the saved $list. | ||||
id | The 16-byte identifier of the saved record set that was returned by a previous $Web_Save_List call. This argument is required. | ||||
opts | A blank delimited set of options that affects the function's behavior. This argument is optional; it can contain the following options:
The default behavior of $Web_Rest_List is as if MOVE were specified. This default behavior can be changed on a thread basis by setting the SRSPARM parameter. |
Status codes
Code | Meaning |
---|---|
0 | No error |
1 | Not a valid $list identifier |
2 | Identifier not found |
Usage notes
- $Web_Restore_List can be used on non-Janus Web Server threads by Janus Web Server customers. In fact, a $list can be saved on one type of thread (say a Janus Web Server thread) and restored on another (say a VTAM 3270 thread).
- A $Web_Restore_List must be issued under the same userid under which the $Web_Save_List was issued. This userid can be the WEBUSER userid.
- If $Web_Restore_List is successful, the original contents of the $list are lost.
- The primary purpose of $Web_Restore_List is to avoid redoing the complex processing required to build a large $list. There are many cases, however, where the original saved $list might be gone, either because of a timeout or an Online being cycled. Web applications that use $Web_Restore_List should be prepared to rebuild the $list if the $Web_Restore_List fails.
- For more information about saved record sets and $lists, see "Janus Web Server Saved Record Set Support" and $Web_Save_List.
Examples
In the following example, the ID for a previously saved $list is retrieved from an invisible form field. If the ID exists and the $list restored, the call to computationally expensive subroutine COMPLEX
is skipped. Otherwise, the parameters for a very complex subroutine called COMPLEX
are retrieved from form fields and the $list is rebuilt. Later in the code, the $list associated with $list identifier %LIST could be saved with $Web_Save_List, whether it had been restored with $Web_Restore_List or built by subroutine COMPLEX
.
* Get the ID and try to restore the $list %ID = $Web_Form_Parm('FINDID') IF %ID NE '' THEN %RC = $Web_Restore_List(%LIST, %ID) IF NOT %RC THEN JUMP TO GOTL1 END IF END IF * Couldn't restore it, rebuild $list %START = $Web_Form_Parm('FINDSTART') %END = $Web_Form_Parm('FINDEND') CALL COMPLEX(%LIST, %START, %END) GOTL1: