SET RUN {ON } OFF controls whether the virtual machine stops when the attention
key is pressed. ON allows you to activate the attention key
(causinq a read of a CP command) without stopping your virtual
machine. When the CP command is entered, it is immediately
executed and the virtual machine resumes execution. OFF places the virtual machine in the normal CP environment, so
that when the attention key is pressed, the virtual machine
stops. When you loq on VM/370, RUN is set off.
LTNEDTT } OFF RCMODE TSAft1 NOTRANS controls the line editinq functions. ON specifies that the
line editing functions and the symbols of the system
are to be used to edit virtual processor console input reqaestSe establishes line editing features in systems
that do not normally provide them. OFF specifies that no character or line editing is to be used for the virtual
machine operating system. When you log on VM/370, LINEDIT is
set on. {
ON} OFF controls whether the virtual machine operating system may use System/370 extended control mode and control registers 1 15. Control reqister 0 may be used with E:MODE either ON or OFF. When you loq on VM/370, ECMODE is set according to
the user's directory option; ON if was specified and OFF if not. NQl§: Execution of the SET ECMODE {ONIOFF} command always
causes a virtual system reset, but does not change the PSW ECMODE bit. controls whether additional checking is performed on virtual IIO requests to DASD in order to support the OS Indexed SeQ1entiai Access Method (ISAH). When you log on VM/370, ISAM is set accordinq to the user's directory options; ON if was soecified and OFF if not. controls ccw translation for CP. NOTFANS can be specified
only by a virtual machine that occupies the virtual=real space. It causes all virtual 1/0 from the issuing virtual
machine to bypass the CP CCW translation except under the following conditions: • SIO tracinq active • First ccw not in the V=R region • I/O operation is a sense command • I/O device is a dial-up terminal • 1/0 is for a non-dedicated device • Pendinq device status
Any of the above conditions forces CCW translation.
To be in effect in the virtual=real environment, SET NOTRANS ON must be issued after the virtual=real machine is loaded via
the Tot command. (IPL sets the NOTRANS option to an OFF condi tion. ) Section 5. Format of CP Commands 131

SET PAGE'( {
ON } OFF controls the pseudo page fault portion of the VM/VS handshakinq feature. PAGEX ON or OFF should only be issued for
a viLtual machine that has the VM/VS handshaking feature It can only be specified for a virtual machine that
has the extended control mode option. PAGEX ON sets
on the Dseudo page fault portion of handshakinq; PAGEX OFF sets it off. you log on to VM/370, PAGEX is set OFF. Also, each time you IPL your virtual machine, PAGEX is set
off. If you want to use the pseudo page fault handling pOLtion of handshaking, you must issue SET PAGEX ON after you
load vour operatinq system. EMSG TEXT TIMEB controls error message handling. ON specifies that both the
error code and text are displayed at the terminal. TEXT that only text is displayed. CODE specifies that only the error code is to be displayed. OFF specifies that no error messaqe is to be displayed. When you log on VM/370, EMSG is set to TEXT. If the console is beinq spooled, the OFF setting is ignored fOL the spooled output and the full error message appears in the spooled output. The other three settinqs result in spooled output that matches the console printout. Not?: recognizes EMSG settings for all error (E), iof;rmation (I), and warning (W) messages, but iqnores the
EMSG setting and displays the complete message (error code and
text) all response (R), severe error (S), and terminal (T)
messaqes. Also, data tyPed in such as a list of names
followiinq a message, will not be controlled by the settinq. }
REAL
controls the virtual timer. ON specifies that the virtual tim2r is to be updated only when the virtual processor is
runninq. OFF specifies that the virtual timer is not to be
updated. REAL specifies that the virtual timer is to be
updated durinq virtual CPU run time and also during virtual wait time. If the REALTIMER option is specified in your VM/370 directory entry, TIMER is set to REAL when you log on;
otherwise it is set to ON when you log on.
r , FFI NIrv ,OFF, ,ON I L controls whether or not CP dispatches a virtual machine and exe=ute its programs on either the main processor or the
attached processor of an attached processor system. Normal mode is AFFINITY OFF, allowing virtual machine execution on
either processor. AFFINITY ON causes the directory to be
interroqated for an affinity setting; if there is none in the
directory, the user receives an informational message. In
uniprocessor mode, affinity is meaningless because all virtual execute on the main processor.
132 VM/37Q CP Command Reference for General Users