Process Open List APIs

The process open list APIs are used to access the data returned by the open list APIs. You can get list entries, find entry numbers in lists and in message lists, find field numbers in lists, retrieve server job information, and close lists. Some examples of these open list APIs are:

• Open List of Job Log Messages (QGYOLJBL)
• Open List of Messages (QGYOLMSG)
• Open List of Objects (QGYOLOBJ)
• Open List of Objects to be Backed Up (QEZOLBKL)
• Open List of Printers (QGYRPRTL)
• Open List of Spooled Files (QGYOLSPL)

These list APIs can improve perceived performance when creating lists. The APIs create and make available to the caller a partial listing of the total set of files, messages, or objects. This list is immediately available to be acted upon, while the remainder of the list is being created. The user does not have to wait for the entire list to be created.

Note: When using Open List APIs, you should use the Close List API to close any open lists after they have been processed and are no longer needed. This frees any internal storage associated with that list. Failure to close open lists when finished may result in the inability to process subsequent Open Lists APIs.

The open list APIs are available only if the Host Servers option of i5/OS^(TM) is installed. You can install this option by using the GO LICPGM function of i5/OS. Select the Install Licensed Programs option on the Work with Licensed Programs display, and select the Host Servers option on the Install Licensed Programs display. Beginning with i5/OS (OS/400) Version 5 Release 3, these and other Open List APIs are available in i5/OS. However, the Host Servers option may still be required so that applications from previous releases continue to function properly. Routing programs are provided with the Host Servers option to transfer requests to the corresponding program in i5/OS.

The process open list APIs and their functions are:

• Change Server Job (QGYCHGSJ) sets the maximum number of auxiliary server jobs allowed for a server job with the iSeries.
• Close List (QGYCLST) closes a previously opened list. Any internal storage associated with that list is freed.
• Find Entry Number in List (QGYFNDE) returns the number of the entry in a list of information for a given key value.
• Find Entry Number in Message List (QGYFNDME) returns the number of the entry in a list of message information for a given key value.
• Find Field Numbers in List (QGYFNDF) returns the number of the entries in a list of information and the value of that entry whenever the value of that field changes.
• Get List Entries (QGYGTLE) allows requests to get entries from previously opened lists on the server.
• Retrieve Server Job Information (QGYRTVSJ) returns information about auxiliary server jobs started for the current job to the system.