Return Codes from CVAFSEQ

On return from CVAF, register 1 contains the address of the CVPL (CVAF parameter list), and register 15 contains one of the following return codes:

Return Code	Meaning
0 (X'00')	The request was successful.
4 (X'04')	End of data (CVSTAT is set to decimal 32), or an error was encountered. The CVSTAT field in the CVPL contains an indication of the cause of the error. Error descriptions are in VTOC Index Error Message and Associated Codes.
8 (X'08')	Invalid VTOC index structure. CVSTAT contains an indication of the cause of the error. Error descriptions are in VTOC Index Error Message and Associated Codes.
12 (X'0C')	The CVPL (CVAF parameter list) is not in your protect key, or is not valid (the ID is not valid, or the length field is incorrect, or the CVFCTN field is not valid). The CVPL has not been modified.
16 (X'10')	An I/O error was encountered.