EDG_EXIT300 exit routine processing

Each time that the EDG_EXIT300 installation exit is invoked, your code should perform the following tasks:

Checks that the function is to gather media information. PL300_MEDINF flag is B'1'.
Uses the information provided as input to the EDG_EXIT300 exit routine to determine if you need to provide media information for this volume. You can check the information provided by O/C/EOV in the IFGTEP area to verify what type of device is being used, media information provided by the drive, and so on. Check the information provided about the volume, such as MEDINF name, MEDIATYPE, and RECORDINGFORMAT. PL300_LSTMDFN contains the media information name.
If required, calls any API provided by your software vendor to retrieve details of the media.
If the media information available to DFSMSrmm is incorrect, sets the correct values in the EDGPL300 output area. For example, to set the external values for the media type and recording format copy the values to the PL300_LSTMDTX and PL300_LSTMDRX fields.
Sets the related flags to indicate the values to be used. When you have set the PL300_LSTMDTX and PL300_LSTMDRX fields, also set the PL300_LSTOFMV and PL300_LSTOFFX flags to B'1' to indicate you have set the output values and that they are to be used by DFSMSrmm. PL300_LSTOFFX indicates that you have set the external values. If you choose to instead set the internal values into PL300_LSTOTDSI, you must ensure that PL300_LSTOFFX is b'0'.

You might not have to make any changes if the information is already correct, or perhaps, the media type is correct and only the recording format has been changed.

The EDG_EXIT300 exit could be extended at any time by IBM to add additional OEM media and library-related functionality. Because of this fact, ensure that you always check that the function is required of the exit and then only perform that required function.

When any exit module sets a non-zero return code, DFSMSrmm issues message EDG0313I. When any exit module abends, DFSMSrmm issues message EDG0314I. If an error in CSVDYNEX occurs at any point in processing, DFSMSrmm issues message EDG0312I. In all cases, O/C/EOV processing continues.