z/VM: CP Commands and Utilities Reference - z/VM - IBM

Examples
function key retrieve buffers available to their own virtual machines. A new SET
RETRIEVE command can be used to increase the number of program function
key retrieve buffers without affecting the contents of the existing buffers.
3. For more information on displaying the current number of program function key
retrieve buffers available to your virtual machine and the maximum number of
buffers that any user may request, see the QUERY RETRIEVE command.
If you issue a SET PFn with no parameters (for the PF key you had assigned to
RETRIEVE), the number of buffers is set to zero, making your RETRIEVE
ineffective.
q pf1
PF01 RETRIEVE BACKWARD
q retrieve
7 buffers available. Maximum of 20 buffers may be selected.
Ready; T=0.01/0.01 16:06:56
set pf1
Ready; T=0.01/0.01 16:07:04
q retrieve
0 buffers available. Maximum of 20 buffers may be selected.
Ready; T=0.01/0.01 16:07:08
If you have two pf keys set for RETRIEVE, for example PF1 and PF12 and you set
PF12 to undefined:
q pf1
PF01 RETRIEVE BACKWARD
Ready; T=0.01/0.01 16:18:52
q pf12
PF12 RETRIEVE BACKWARD
Ready; T=0.01/0.01 16:18:58
q retrieve
7 buffers available. Maximum of 20 buffers may be selected.
Ready; T=0.01/0.01 16:19:08
set pf12
Ready; T=0.01/0.01 16:19:15
q retrieve
7 buffers available. Maximum of 20 buffers may be selected.
Ready; T=0.01/0.01 16:19:20
then it does NOT set the buffer to zero.
SET RETRIEVE works to set a number of buffers for you even if you have no pf
keys set to retrieve. However, if you then set your all your pf keys to null, the
retrieve buffer is set to zero. Suppose you have only two pf keys set, PF3 and PF5:
q pf
PF01 UNDEFINED
PF02 UNDEFINED
PF03 IMMED INFOLIST
PF04 UNDEFINED
PF05 IMMED EXEC MAILBOX
PF06 UNDEFINED
.
.
PF24 UNDEFINED
Ready; T=0.01/0.01 17:05:03
and you set retrieve but then set PF3 and PF5 to null:
SET RETRIEVE
Chapter 2. CP Commands 1373