EXAMINING OS/iS VIRTUAL MACHINE OUTPUT To examine a job's output executed under the OS/VS virtual machine, sFeol the unit record output to the user's own Now read the
file in the virtual card reader onto a eMS disk by using eMS BEADCABt command:
readcard pli27 job
The CMS TYPE command or editor can then be used to scan such a file.
If programming errors occurred during the execution of the job
stream, the eMS editor can be used to make corrections to the source
program, ccrrect job control statements, or resolve any other executicn
problems. After aaking these corrections, resubmit the job stream.
Using More than One Virtual Machine A user can run multiple systems, each in its own virtual machine and
each contrclled from its own terminal. However, if multiple terminals
are not available, a user can use one terminal to control all systems
but only one at anyone time.
This aFFroach combines the alternating system and batch techniques. Separate userids are used to run OS/VS in one virtual machine and to
prepare jobs and examine OS/VS output in a CMS virtual machine.
After submitting a job stream under the eMS userid: issue the DISCCNN or LOGOFF command (depending upon how soon the user intends to log onto
the CMS ID again). The terminal is now free to be used for running the OS/VS job stream under the OSVS userid:
logon cmsid
(route jobs to OSVS user)
disconn
logon osvs
(run jobs) Section 4. OS/VS in a Virtual Machine 135

The procedures for same as thcse used in runn1ng IIcde. The prillary difference punch and printer to the other
to the user's own userid:
logon cllsid
sp pun osvs • (route jobs to OSVS user)
disconn
logon osvs Icp sp prt cmsid Icp sp pun cmsid • (run 0 S/VS jobs) DISCONNECTION CONSIDERATIONS with two virtual machines are lIuch the
a single virtual machine in alternating
is that a user now spools the virtual
virtual machine instead of spooling them When using lIore operating systems,
than one userid to
consider:
alternate communications between • How OS/VS may read additional jobs from the card reader? • What happens when a read is issued at the disconnected OS/VS virtual
console? • What happens to the console output of the disconnected virtual
machine? When using CMS to route jobs to a disconnected OS/VS virtual machine, spool the OS/VS reader with the CONT operand of the CF SPOOL command: spool reader cont
This cOllmand allows the OS/VS reader to read more than a single job
at a time without opera tor intervention. When running OS/VS disconnected, a 15-minute time-out begins when a
console read occurs. If the read does not occur within the 15 minutes, VM/370 automatically logs off the virtual machine. Whenever running OS/VS disconnected, it is suggested that a console
leg be created. This log provides a user with a history of what jobs
were run. It can also indicate any unusual circumstances that occurred
during the terminal session.
136 IBM VM/370 Operating systems in a Virtual Machine