$Session_Open
Open a session
Note: Many $functions have been deprecated in favor of Object Oriented methods. The OO equivalent for the $Session_Open function is GetSession.
$Session_Open opens a previously created session.
Syntax
%rc = $Session_Open(sesid, [owner], [timeout])
| %rc | A returned zero, indicating success, or a number indicating the cause of error, if there is one. |
|---|---|
| sesid | The ID of the session to be opened. This is a required argument. |
| owner | The userid that owns the session to be opened. An owner value of asterisk (*) means that the session is public, that is available to all users.
This optional argument defaults to the creating user's userid. |
| timeout | The time to wait for an in-use session to be closed before giving up. A value of -1 indicates to use the value of the SRSDEFTO parameter. This argument defaults to -1, that is, the value of the SRSDEFTO parameter. |
Return codes
%rc is set to 0 or to an error indicator.
0 - No errors 1 - Session not found 2 - Session in use
Usage notes
Use of a non-zero timeout for $Session_Open can be useful for single-threading multiple threads through a request or for dealing with timing problems where it's possible for a request for a session to come in before the previous one is completely done. This is quite possible in Janus Web Server applications where one of these occurs:
- A request resulting from a redirect comes in before the redirecting thread has closed the session
- A user cancels a request and then resubmits it while the original request is still processing and so has the session open.
Example
The following retrieves a session ID from a cookie and opens it:
%sesid = $Web_Get_Cookie('SESID') %rc = $Session_Open(%sesid)