IPDS pass-through

IPDS pass-through allows you to process some SCS and IPDS spooled files more efficiently.

Before printing, SNA character string (SCS) files are converted to Intelligent Printer Data Stream (IPDS) files. These are then converted to Advanced Function Presentation data stream (AFPDS), and then to printer-specific IPDS. Also, IPDS files are converted to AFPDS, then are converted to printer-specific IPDS. The final IPDS files have specific commands for your printer. You can choose to skip the conversion to AFPDS and to printer-specific IPDS. This is called IPDS pass-through. IPDS pass-through is specified on a PSF configuration object.

Specifying IPDS pass-through in the PSF configuration object allows only those spooled files eligible for IPDS pass-through to bypass the extra transforms. Those spooled files not eligible for IPDS pass-through are still transformed to AFPDS and then to printer-specific IPDS.

Figure 1 shows the data stream origination, flow, and conversion for a spooled file when IPDS pass-through support is enabled.
Figure 1. Spooled file conversion with IPDS pass-through support
Data stream origination, flow, and conversion for a spooled file when IPDS pass-through support is enabled
Consider using IPDS pass-through if one of these apply:
  • You have applications that generate SCS or IPDS data streams when printing to an Advanced Function Presentation (AFP) printer.
  • You are using applications such as the IBM® Business Graphics Utility for IBM i licensed program, GDDM, or Virtual Print that do not support AFPDS.
  • Your SCS or IPDS application does not contain any reference to overlays or to host font character sets.

Limitations of IPDS pass-through

These IPDS pass-through limitations determine whether a spooled file or printer is eligible for IPDS pass-through:
  • Some SCS or IPDS spooled files are not eligible for IPDS pass-through. One such situation is when they contain special functions that require being transformed to AFPDS for the spooled file to print correctly.
    Spooled files that contain the following data or printer file attributes are not eligible for IPDS pass-through:
    • For SCS or IPDS data streams, the data stream contains Image Object Content Architecture (IOCA) or IM1.
    • For SCS or IPDS data stream, a front or back overlay was specified in the printer file.
    • For SCS data stream, IGCDTA(*YES) was specified in the printer file.
    • For SCS or IPDS data streams, MULTIUP with REDUCE(*NONE) was specified in the printer file.
    • For SCS or IPDS data stream, a form definition was specified in the printer file.
    • The EDGESTITCH or CORNERSTPL finishing operation is specified in the printer file.

    If IPDS pass-through is specified but the spooled file is ineligible, a diagnostic message is sent and the spooled file is processed as usual. It is transformed to AFPDS and then to printer-specific IPDS.

  • IPDS pass-through support is available for any IPDS printer that provides resident fonts. This is because the resident fonts referenced in the data stream must be mapped to the host fonts, which are downloaded to the printer. Therefore, IPDS pass-through support is not available for these IPDS printers: 3820, 3825, 3827, 3828, 3829, 3831, 3835, and 3900-001.

    When a printer writer is started to an AFP(*YES) printer that does not support IPDS pass-through and IPDSPASTHR(*YES) is specified, a diagnostic message is sent. The spooled file is transformed to AFPDS and then to printer-specific IPDS.