_GENPD contains the name of the current printer driver interface program. By default, this program is the application supplied with FoxPro, GENPD.APP.

In FoxPro for Windows, GENPD.APP is only used to print character-based reports created in FoxPro for MS-DOS.

In FoxPro for Macintosh, a printer driver interface program isn't necessary to print character-based reports created in FoxPro for MS-DOS.

In FoxPro for MS-DOS, the program whose name is stored in _GENPD is executed when you do one of the following:

• Choose the Printer Driver Setup check box in the Printer Setup dialog.
• Choose the Set Printer Driver check box in the Report Writer's Page Layout or the Label Designer's Label Environment dialog.
• Issue SET PDSETUP.
• Store a printer driver setup name in _PDSETUP.
• Specify a default printer setup before starting FoxPro.
If you store the name of your printer driver interface program in _GENPD, your program is executed when one of the events listed above occurs.

If you do not include an extension with your printer driver setup program when you store its name in _GENPD, FoxPro looks for a version of the program in the following order and executes the program if found:

1. An executable (.EXE) version of the program

2. An application (.APP) version of the program

3. A compiled (.FXP) version of the program

4. The program (.PRG)

The printer driver interface program you specify in _GENPD can take virtually any form, but it must have a PARAMETERS statement as its first line. FoxPro passes two parameters to the program, a numeric value and name of the printer driver setup.

The first parameter is one of the following numeric values:


• FoxPro passes 0 to the program if you execute the program by choosing the Printer Driver Setup check box in the Printer Setup dialog, issue SET PDSETUP, or store a printer driver setup name in _PDSETUP.
• FoxPro passes 2 to the program if you choose the Set Printer Driver check box in the Report Writer's Layout dialog or in the Label Designer's Label Environment dialog.

To prevent recursion, it is a good idea to test the numeric parameter passed to the printer driver setup program. For example, you could store a printer driver program name in _PDRIVER that automatically executes the PDONLOAD procedure in the printer driver program. Your PDONLOAD procedure executes your printer setup interface application and passes it a value of 1.

The printer setup interface application tests the numeric value. If the value is 1, a printer driver program name should not be stored in _PDRIVER in the program. If, in this case, a printer driver program name is stored in _PDRIVER, PDONLOAD is automatically executed again and your printer driver setup program is executed again in an infinite loop.

The second parameter FoxPro passes to the printer driver setup program is the name of the printer driver setup specified in SET PDSETUP or stored to _PDSETUP. If you execute the printer driver setup program by choosing the Printer Driver Setup check box in the Printer Setup dialog, FoxPro passes a question mark (?) as the second parameter to the program specified in _GENPD.

Other Resources

Backward-Compatible Language Elements
Language Reference (Visual FoxPro)