Your EFS program can return informational or critical messages. A return code of 0 in general register 15 indicates an informational message while a return code of 16 indicates a critical message. If the EFS program has no messages to send after a Major Call, it must zero the message list address in the EFS interface parameter list.

At Major Call 2, if the EFS program finds a syntax error in a control statement, it can return an offset relative to the start of the string to indicate the location of the error. DFSORT first prints the control statement in error and then prints another line containing a dollar symbol ($) at the location indicated by the offset.

Because DFSORT associates the relative offset with a critical message, the EFS program must return with a return code of 16 in general register 15. If a relative offset is returned for an EXEC PARM, the relative offset will be ignored. The EFS program must free any storage it acquired for its messages.

The length field values must not include their own length.

The message list format follows:

An asterisk (*) indicates that the length is determined by the corresponding length field.

DFSORT imposes no restrictions on the format of the messages returned by an EFS program. If you wish, you can use the DFSORT message format so that messages in the message data set are consistent in appearance. For a description of the message format used by DFSORT, see z/OS DFSORT Messages, Codes and Diagnosis Guide