OPEN
The assembler calls the exit with a request type of 1 (OPEN) at the start of the assembly. This is the first call to the exit.
The exit sets the return code in the
Exit Parameter List to one of these values:
- 0
- Instructs the assembler to open the primary input data set, and
supply the primary input records to the exit in later PROCESS calls.
- z/VM® and z/OS®
- The buffer length field can be set to any value from 121 to 255. If the listing data set has a variable-length record format, the LRECL assigned is 4 bytes greater than the value the exit returns. If the value is less than 121 or greater than 255, the assembler issues message ASMA402W and does not call the exit for any further processing.
- z/VSE®
- The buffer length field can be set to any value from 121 to 133. If the
value is less than 121 or greater than 133, the assembler issues message
ASMA402W and does not call the exit for any further processing.
If you assign SYSLST to a disk data set in your JCL, the record length must be 121.
Note: A reason code of 16 indicates a REINIT call is required. - 4
- Indicates that the exit supplies the primary input records to
the assembler in later READ calls. If you want to provide the assembler
with the values for the system variables &SYSIN_DSN, &SYSIN_MEMBER,
and &SYSIN_VOLUME, the user exit must set the reason code to 4
and place the values in the data set name, member name, and volume serial fields
of the exit-specific information block.
The assembler also shows this information in the Diagnostic Cross
Reference and Assembler Summary section of the listing, and includes
it in the associated data file Job Identification record. Note: A reason code of 16 indicates a REINIT call is required.
- 16
- Instructs the assembler to open the primary input data set, and make no further calls to the exit.
If you provide a character string in the str1 suboption of the EXIT assembler option, the buffer pointer points to the character string, and buffer length contains the length of the character string. The buffer length is set to zero if there is no character string.