Data Conversion

Stream Files: DFM offers limited support of data conversion for stream files. DFM APAR OW16828 for DFSMS/MVS 1.3 provides enhancements to end users who install DDM client enhancements, as described in informational APAR II09011. These DDM client end users can now retrieve z/OS® stream data and have it converted to the single-byte code page associated with their workstation.

Using commands equivalent to DFM/2 commands DFMDRIVE SETPARM and DFMDRIVE ASSIGN, the DDM client end user can specify z/OS target parameters that will trigger stream data conversion. The z/OS target parameters are as follows:

BINARY

Specifies no stream data conversion. BINARY is the default.

TEXT

Specifies stream data conversion and tags new stream file with the workstation CCSID (PP_CCSID). The current workstation CCSID is automatically passed in by the DDM client, but may be overridden by the PC_CCSID parameter. When TEXT is specified, the following parameters are also valid:

CRLF maintains record boundaries using carriage return and line feed as the delimiters. CRLF is the default.
NL maintains record boundaries using the new line character as the delimiter.
LF maintains record boundaries using the line feed character as the delimiter.
NOEOL does not maintain record boundaries and treats any delimiters or padding as data.

PC_CCSID=ddddd

Specifies the workstation CCSID, ddddd is the decimal CCSID. The CCSID is ignored for BINARY processing and new files are tagged with a CCSID of X'FFFF' to indicate they are not converted. The PC_CCSID setting does not affect the retrieval of binary files, only the TEXT parameter triggers data conversion.

HOST_CCSID=ddddd

Specifies the CCSID used for stream files created on the target system or for legacy data sets with no explicit CCSID defined. ddddd is a decimal CCSID from 0 to 65535. A CCSID value of 65535 prevents steam data conversion. If omitted, text files are created or retrieved using the current CCSID from SYS1.PARMLIB(DFM00).

The TEXT parameter triggers stream data conversion when required and when the combination of CCSIDs is supported by CDRA.

If the file is not tagged with a CCSID and TEXT processing is specified by the workstation, legacy files not tagged with a specific CCSID will default to the CCSID as specified in SYS1.PARMLIB(DFM00).

The HOST_CCSID parameter is not used to override an explicit CCSID associated with a file. It is only used to tag new files or to access files that have no CCSID set.

Record Files

DFM does not provide data conversion services for record files. When DFM stores record files on z/OS, the data is stored in the format sent by the source. If a target system application requires a different data format, data conversion can be done by a source application.

For example, if data is sent from a DDM client source system in ASCII format, it requires conversion to EBCDIC before it can be read by a standard z/OS application. This conversion from ASCII to EBCDIC can be done by the conversion utility provided by the Distributed FileManager component of SMARTdata UTILITIES.