For the SOURCE and LIBRARY exits

These values are provided:
0
No additional information available.
1
New information is available in the Exit-Specific Information block. The assembler updates this block whenever the primary input data set changes.

For example, the SOURCE input might be a concatenation of data sets. When the first data set is opened, and when each subsequent concatenated data set is opened, this value is set to 1 to inform the exit that a data set switch has occurred. It is also set for LIBRARY processing to inform the exit which data set in the concatenation is being used to provide the specific member.

2
For the LIBRARY exit, when the request type is FIND MACRO or FIND COPY, the copy code or a macro should resume at the saved record position.
3
For the LIBRARY exit, when the request type is FIND MACRO or FIND COPY, copy code or a macro definition is currently being processed. The user exit should save the position within the current member to allow it to be resumed when the new member has been processed.

See Nesting COPY instructions and macro definitions.