Support for SBCS languages

SBCS (single byte character set) encoding is the default encoding for both control and data connections, and is the encoding specified in FTP RFCs such as RFC 959. You can specify SBCS encoding on either the control or data connection.

Some methods of specifying alternate translation tables for the FTP client apply to both the control and data connection. If the translation table you need for data transfer does not support the standard encodings for the portable character set, you should establish different translation tables for the control and data connections to ensure that FTP commands and replies are translated correctly.

Specify SBCS encoding for the data connection with one of the following methods:

Code statements in FTP.DATA: SBDATACONN and SBTRANS.
Use LOCSITE SBDataconn or LOCSITE XLATE subcommands to set the code page.
Place an MVS™ data set containing a binary translate table in the FTP client's search order for TCPXLBIN data sets. Use the CONVXLAT utility to generate an MVS data set containing the binary translation table you require. See SBCS translation table hierarchy in the z/OS Communications Server: IP Configuration Reference for the search order used by the FTP client.
Specify the TRANSLATE parameter as an FTP client start option. The translate parameter applies to both the control and data connections.
If you need to establish different translate tables for the control and data connection, use one of the other methods to establish the translate table, or else change either translate table after starting the client.

If the table you specified with the TRANSLATE parameter does not support the POSIX portable character set, start the client without specifying a host name so the client does not attempt to send commands on the control connection before the correct translation table is established. Then change the client's translation table after starting FTP.

You can specify different conversions for the control connection by using any of the following methods:

Code CTRLConn statements in the FTP.DATA file.
Place an MVS data set containing a binary translate table in the FTP client's search order for TCPXLBIN data sets. Use the CONVXLAT utility to generate an MVS data set that contains the binary translation table you require. See SBCS translation table hierarchy in the z/OS Communications Server: IP Configuration Reference for the search order used by the FTP client.
Use the LOCSITE CTRLCONN subcommand.
Specify the TRANSLATE parameter as an FTP client start option. If you use this method, the table applies to both control and data connections.

If you code EXTENSIONS UTF8 in the client FTP.DATA file, the control connection uses 7-bit ASCII for commands and, when negotiated with the server, UTF-8 encoding of path names. The client can override the EXTENSIONS UTF8 statement by using the FTP TRANSLATE start parameter or by issuing SITE and LOCSITE subcommands. However, the client cannot resume UTF-8 encoding on the control connection until you restart the client.

Extended trace point ID 81 is available for tracing the translate tables. When set to ON, 256 bytes of each translate table can be traced as follows:

When the FTP STAT command is sent to the server, the translate tables being used by the server for the control and data connection are traced. When the FTP LOCSTAT subcommand is entered, the translate tables being used by the client are traced.
When the LOCSITE subcommand is entered to change the client translate table, the client traces the new table. When the server receives a SITE command to change the translate table, the server traces the new table.

See the SITE subcommand - DUMP parameter for instructions for activating extended trace point 81 for the server. See the DUMP subcommand—Set extended trace options for instructions for activating extended trace point 81 for the client.