Variable-length records

 

If your iSeries™ source server is running OS/400^® Version 2 Release 1 Modification 1, DDM supports variable-length record files as defined in the DDM architecture.

You can use DDM on your iSeries server to open variable-length record files on target systems that are not iSeries or S/38 servers. (Initially you can open variable-length record files if you are not opening the file for updating.) For subsequent read operations, variable-length records are padded with blanks to the maximum record length of the file. Trailing blanks are removed on write operations.

If your iSeries source server is running OS/400 Version 2 Release 2 in addition to the Version 2 Release 1 Modification 1 support mentioned earlier, iSeries variable-length record access is supported using DDM. Variable-length records can be used when opening a variable-length record file on target servers that are not iSeries or System/38™ servers. For subsequent read operations against files opened with variable-length records, variable-length records are padded with blanks to the maximum record length of the file. Also, the actual record length (maximum record length of file minus the number of padded blanks) is appended to the end of each record. For write operations, the actual record length is used to determine the length of the variable-length record to send to the target server. No counting of trailing blanks is necessary to determine the actual length of record data.

The target DDM iSeries servers running at Version 2 Release 2 also support variable-length record files. A variable-length record file can be created on the iSeries target server as a result of a create file request.

 

Parent topic:

Work with access methods for DDM

 

Related reference

DDM commands and parameters