Printing display screens

If your printing requirement is to copy a display screen to a printer, you have choices additional to the ones already described. Some of these are provided by the terminal hardware itself, and some by CICS®.

Some of the CICS support also depends on hardware features, and so your options depend on the type of terminals involved and, in some cases, the way in which they are defined to CICS. For more information, see TERMINAL resources.

CICS print key

The first such option is the CICS print key (also called the local copy key). This option allows a user to request a printed copy of a screen by pressing a program attention key, provided the terminal is a 3270 display or a display in 3270 compatibility mode. Print key support is optional in CICS; the system programmer decides whether to include it and what key is assigned. The default is PA1. See the PRINT option in the DISPLAY and PRINT options for combined lists of information.

The print key copies the display screen to the first available printer among those defined as eligible. Which printers are eligible depends on the definition of the display terminal from which the request originates, as follows:
  • For z/OS® Communications Server 3270 displays defined without the “printer-adapter” feature, the printers named in the PRINTER and ALTPRINTER options of the terminal definition are eligible. PRINTER is to be used if available; ALTPRINTER is second choice. If both are unavailable, the request is queued for execution when PRINTER becomes available.
  • For the 3270 compatibility mode of the 3790 and a 3650 host conversational (3270) logical unit, the same choices apply.
  • For z/OS Communications Server 3270 displays defined with the printer-adapter feature, copying is limited to printers on the same control unit as the display. The printer authorization matrix within the control unit determines printer eligibility.
  • For a 3270 compatibility mode logical unit of the 3790 with the printer-adapter feature, the 3790 determines eligibility and allocates a printer for the copy.
  • For a 3275 with the printer-adapter feature, the print key prints the data currently in the 3275 display buffer on the 3284 attached to the display.

Where CICS chooses the printer explicitly, as it does in the first three cases above, the printer has to be in service and not attached to a task to be “available” for a CICS print key request. Where a control unit or subsystem makes the assignment, availability and status are determined by the subsystem. The bracket state of the device typically determines whether it is available or not.

ISSUE PRINT and ISSUE COPY

An application can initiate copying a screen to a printer as well as the user, with the ISSUE PRINT and ISSUE COPY commands. ISSUE PRINT simulates the user pressing the CICS print key, and printer eligibility and availability are the same as for CICS print key requests.

You can use the ISSUE COPY command to copy a screen in a task that owns the printer, as opposed to the task that owns the terminal which is to be copied. It copies the buffer of the terminal named in the TERMID option to the buffer of the principal facility of the issuing task. The method of copying and the initiation of printing once the copy has occurred is controlled by the “copy control character” defined in the CTLCHAR option of the ISSUE COPY command; for the bit settings in this control character, see IBM 3270 Data Stream Device Guide. The terminal whose buffer is copied and the printer must both be 3270 logical units and they must be on the same control unit.

Hardware print key

Some 3270 terminals also have a hardware print key. Pressing this key copies the screen to the first available and eligible printer on the same control unit as the display. This function is performed entirely by the control unit, whose configuration and terminal status information determine eligibility and availability. If no printer is available, the request fails; the user is notified by a symbol in the lower left corner of the screen and must retry the request later.

BMS screen copy

Both the CICS and hardware print keys limit screen copies to a predefined set of eligible printers, and if more than one printer is eligible, the choice depends on printer use by other tasks. For screens created as part of a BMS logical message, a more general screen copy facility is available. Users can print any such screen with the “page copy” option of the CICS transaction for displaying logical messages, CSPG. With page copy, you name the specific printer to receive the output, and it does not have to be on the same control unit as the display. For information about CSPG, see CSPG - page retrieval.