Function
To allow program output on a *LP device to be sent to magnetic tape instead of filestore or an online printer. This gives the security needed for restarts, multiple copies, and special output format requirements. Offline processing to microfiche or special devices is possible. This has been particularly valuable by small commercial sites for three reasons:-
A print program and controlling macro, with restart facilities, is also
provided.
(Mend Exchange Scheme modification M550).
Format
ZOFFLINE peripheral name,file description
Forbidden contexts
NO CORE IMAGE
Execution
The job's ONLINE or ASSIGN command for the printer is replaced by the command ZOFFLINE.
The file description is similar to the GET command and the qualifiers FROZEN, OWNERACC, TRAPGO and TRAPSTOP may be included. The effect of using Property identifiers is undefined. A pool tape will be obtained and entered in the relevant directory, subject to normal requirements of ownership, SPACEMT budget, and specific online tape limits. The peripheral name must be of type *LP or *02 and must be the first parameter.
The tape is obtained from the pool and a header label written. When the program runs, output on the channel is buffered into blocks of maximum size 512 words and written to the tape. A start-of-data sentinel is written when the first PERI is executed. Transfers may be mode #0 or mode #4. A new block is started for each New Page PFCC (#11 or #51); this is to simplify restart procedures. On normal termination, the incomplete buffer is written, followed by a standard end-of-simple-file trailer label.
If the tape is filled, an end-of-reel sentinel is written. This is held back until the end of a print page if possible (up to 10 blocks after the end-of-tape warning. The PERI then fails OUTOUT *LPn FULL.
If there is a physical failure on writing to the tape, the current PERI is failed ONLINE *LPn FAIL. This is normally catastrophic, since an unknown number of preceeding lines of print may have been lost.
In the above two cases, further PERI attempts on the same taoe are rejected with the same error message. The full tape case can be handled by reconnecting the channel to a file, printer, or fresh taoe; rewind of the old tape is always autonomous to avoid delay to the job.
On the unfortunate occassions when a close of the tape fails in writing the last
buffer or trailer label a GEORGE error message is given:-
ERROR IN <command>: *MT FAILURE IN CLOSING *LPn
In the case of a REL or DEL(TY) extracode, command error action will not occur until control is returned to GEORGE; the <command> will be ENTER, RESUME, MONRESUME, etc. Once a tape fail is detected, no further writing is attemped.
All error messages not mentioned above are standard.
Example
ZF *LP1,LP-PAYSLIPS