Page of GC20-1807-7 As Updated April 1, 1981 by TNL GN25-0829 Using the 3800 Printer as a Real Spooling Device VM/370 allows users of spool files to print their files on an IBM 3800 printing Subsystem. The copy modification, forms overlay, character
modification, and multiple copy features are fully supported. However,
when the 3800 is used as a real spooling device, only one character
arrangement table may be specified for each spool file. In addition,
the entire spool file must be printed with the same line spacing on each
page. Parameters on five commands enable the user to take advantage of the 3800 printer's capabilities. The CHANGE, SPOOL, and START commands
allow the user to specify the character arrangement table, copy
modifications, forms overlay, and FCB to be used for printing. The BACKSPAC and QUERY commands also support the 3800 Two utilities, GENIMAGE and IMAGELIB, construct and modify the
character arrangement tables, graphic modifications, copy modifications,
and FCBs used by the 3800. DIAGNOSE Code X'74' is invoked by IMAGELIB
to load and save this control information as a named system.
Finally, the NAME3800 macro instruction allows the user to create the
named system that contains the control information needed to print a
spool file. SPECIFYING PRINTER OPTIONS Five parameters on the SPOOL and CHANGE commands support the 3800 printer as a real spooling device. (See CP ggfgr§Q£g General for detailed coding information.) • FLASH - identifies the form overlay, if any, to be used when printing
the file • CHARS - names the character arrangement table to be used to print the
file • MODIFY - indicates the copy modification module, if any, to be used
when printing the file • FCB -specifies the name of the forms control buffer to be used for
the file • COpy - indicates the number of copies to be printed
The START command includes parameters that enable the VM/370 operator
to name the character arrangement table and FCB to be used for the
separator page. The operator can also identify the forms overlay
currently loaded in the 3800 via the FLASH operand of the START command.
In addition, the operator uses the IMAGE parameter to specify the named
system to be used to print the spool file. Finally, by specifying the PURGE parameter, the operator can purge all spool files that cause errors when loaded into the 3800. See Operator's Guide-for
further information on the START command. ------ ---------- ----- CR EATl tr.; CONTROL TABL ES VM/370 the as/vs utility IEBIMAGE to create and dynamically modify
character arrangement tables, copy modifications, graphic modifications,
and FCBs. Two service programs, GENIMAGE and IMAGELIB, interface with
IEBIMAGE. Part 2. Control Program (CP) 227

April 1, 1981 GENIMAGE creates or modifies text files on a CKS disk. These text
files contain the images to be used by the 3800 Printing Subsystem. IKAGELIB loads the new or changed text files created by GENIKAGE into
virtual storage. When all the files are loaded, DIAGNOSE Code X'74' is
invoked to save these files as a named system. See Y]iL170 Pl§..illli!!g System Guide or more information
on IMAGELIB and GENIMAGE. STORING AND LOADING CONTROL TABLES As part of VM/370 support of the 3800 printer, character arrangement
tables, copy modifications, graphic modifications, and FCBs are stored
in a named system. PrioI:' to printing a spool file, the VK/370 operator specifies a named
system on the IMAGE parameter of the START command. The control tables
specified for the file (via the SPOOL and CHANGE commands) are loaded
into the 3800 from that named system and the file is printed.
The NAME3800 macro instruction establishes the named system at system
generation. See the further information. RECOVERING FROM I/O ERRORS Because the actual printing of lines on the page is slower than the
output of lines from the processor, spool files are placed into a
delayed purge queue to await printing by the 3800. Only when the
maximum number of files are in the queue will the first one actually be
purged. The size of the queue can be specified at sysgen via the DPMSIZE parameter on the RDEVICE macro instruction. DPMSIZE can have a
maximum value of nine.
Because spool files are queued, the BACKSPAC command may be used for the 3800 printer to restore pages that are lost when an I/O error
occurs. In addition, the operator may specify the EOF parameter, which
indicates that backspacing should begin at the end of the file and
continue for the number of pages specified. See the for more information on the BACKSPAC command. DISPLAYING PRINTER CONTROL INFORMATION The QUERY command enables G-, B-, and D-privilege users to display the
names of the character arrangement table, copy modification, and FeB
currently in effect for a spool file or a virtual printer. In addition,
the VM/370 operator can use the QUERY command to determine the image
library used and the forms loaded on a real 3800. See the Guide for details on the QUERY command.
228 IBM VM/370 System programmer's Guide