You can use pipe-device arrays to connect custom programs to the input or output of the onpload utility. Although pipe-device arrays provide the simplest way to customize the input or output of onpload, connecting the standard I/O of programs is less efficient than directly incorporating the functionality into onpload.

1. Use the API described in Available API Support Functions to write the driver.
2. Add the driver name to the onpload database.

   For details, see Using the Drivers Window.

3. Select the driver from the Driver selection list in the Format Options window.

   For details, see Format Options.