ETERNUS SF XL-DATA/MV V13 User's Guide

4.1.7.2 Filter Command Input and Output

Perform the following to create the input/output of the filter command:

Using the Filter Command on the Server System

This section explains the execution of the filter command in a UNIX/IA server system.

When sending data

When the client system sends data to the server system (when starting the mftfsend command), the filter command handles data in the following methods:

Data input : Standard input
Data output: Standard output or file output

The XL-DATA/MV daemon or service passes the data that is sent by the client system via the data transfer volume, to the standard input of the filter command.

As mentioned above, there are two types of filter command outputs (i.e., standard output and file output). The input method must match the specifications when executing the data transfer and the format of the filter command.

The relationship of the data flow between the daemon/service and filter command is shown below.

[For standard output]



[For file output]



The target of data output by the transfer command (mftfsend command) depends on whether or not the string value of [target file name] specified in the transfer command is the same as the optional part of string value of [filter command] specified in the environment variable.
If the string value is the same, the file output is used. Otherwise, standard output is used.
This specification changes the operation of the daemon/service as shown above.

---



When using the filter command for the file output, the target file is created by the daemon or service of the XL-DATA/MV, then the filter command is called.
If the existence of the target file for saving the data is an issue, proceed with care when using the filter command.

---

When receiving data

When the client system receives data from the server system (when starting the mftfrecv command), the filter command handles data in the following methods:

Data input : Standard input or file input
Data output: Standard output

As mentioned above, the XL-DATA/MV daemon or service has two methods of input for the filter command: standard input and file input.
The input method must match the specifications when executing the data transfer and the format of the filter command.

The daemon or service receives the filtered data by the standard output of the filter command, and passes that data to the client system via the data transfer volume.

The relationship of the data flow between the daemon/service and filter command is shown below.

[For standard input]



[For file input]



The source of data input for the transfer command (mftfrecv command) depends on whether or not the string value of [source file name] specified in the transfer command is the same as optional part of the string value of [filter command] specified in the environment variable.
If the string value is the same, the file input is used. Otherwise, standard input is used.
This specification changes the operation of the daemon/service as shown above.

Using the Filter Command on the Client System

To execute the filter command on the client system, shell pipes (such as those shown below) can be used when executing the transfer command.
Refer to the section on the Transfer command for the option parameters of the transfer command.

[For the mftfsend command (UNIX server)]

Filter command | mftfsend   Target file name of the server system

[For the mftfrecv command (IA server)]

mftfrecv.exe   Source file name of the server system | Filter command

Using filter commands with the mftfsend command

Create a filter command that passes the filtered data to the standard input of the mftfsend command, as shown below.

Using filter commands with the mftfrecv command

Create a filter command that filters data taken from the standard input, where this data is the standard output of the mftfrecv command, as shown below.

---

When the mftfrecv command is being used with the client system side filtering command, if the filtering command finishes while the mftfrecv command is still passing data to the standard output, the mftfrecv command returns an "Internal Error (system message = pipe closed)" error finish.