Exit Program for Close Stream File (QHFCLOSF) API

Before applications can use the Close Stream File (QHFCLOSF) API with your file system, you must:

1. Write an exit program that performs the close stream file operation on behalf of the API. For a detailed description of the API and its calling parameters, see Close Stream File (QHFCLOSF) API.
   
   
2. Give the exit program's name when you register the file system with the Register File System (QHFRGFS) API.

After that, when an application calls the QHFCLOSF API, the API calls your exit program and passes it the parameters specified by the application. Your exit program performs the work and returns any data to the API. The API passes the data back to the calling application.

Authorities and Locks

None.

Required Parameter Group

The API passes this information to your exit program:

Operation (CLOSF)

INPUT; CHAR(5)

The abbreviation for the operation being performed (CLOSF).

File system job handle

INPUT; CHAR(16)

The work area or job identifier for use by the file system.

The following parameter is the same as the parameter for the API.

Open file handle

INPUT; CHAR(16)

Optional Parameter Group

If your file system was registered with a Version 2 Release 3 Modification Level 0, this parameter is passed to your exit program for the Close Stream File API.

Close type

INPUT; CHAR(1)

The type of close operation to be performed. Valid values are:

0	If the exit program cannot close the file, HFS does not mark the file as closed.
1	Unconditional close. HFS marks the directory as closed regardless of what valid exception is returned by the exit program. HFS may call your exit program for an unconditional close at the end of the job and during the reclaim resource processing. If your file system is called to unconditionally close a file, the file should not be marked as open by the file system when control is returned to HFS.

HFS uses the close type value 0 when the QHFCLOSF API is called to close the file. The unconditional close type value 1 is used when:

• The job ends.
  
  
• Reclaim resource processing is done.
  
  
• The Deregister File System (QHFDRGFS) API is called, and the job is using the file system to be deregistered.

API Functions

The QHFCLOSF API performs the standard functions described in Standard HFS API Functions.

Exit Program Requirements

You must create an exit program that performs the standard functions described Standard HFS Exit Program Requirements and these additional functions:

• Releases any byte locks that the job has on the file.
  
  
• Closes the file and invalidates the file system job handle so that the handle cannot be used again.

Error Messages for Exit Program Use

This section lists the messages that the exit program can return to the API.