The Ctrl/Y function provides a general-purpose escape from the current
operation. The Ctrl/Y function can generally be used during an
interactive terminal session to interrupt the current command, command
procedure, or program image.
The SET NOCONTROL=Y command can be used for special application
programs. When the SET NOCONTROL=Y command is executed in a
system-specified command procedure for a particular user at login, that
user can communicate only with the application program that controls
When you press Ctrl/Y and SET NOCONTROL=Y is in effect, the INTERRUPT
message is displayed, but no interruption takes place.1
SET NOCONTROL=Y also disables the Ctrl/C cancel function for all
commands and programs that do not have special action routines
responding to the Ctrl/C function.
The Ctrl/T function displays a single line of statistical information
about the current process. When you press Ctrl/T during an interactive
terminal session, it momentarily interrupts the current command,
command procedure, or image to display statistics. The statistical
information includes the node and user names, the current time, the
current process, CPU usage, number of page faults, level of I/O
activity, and memory usage. For example:
BOSTON::SMITH 16:21:04 EDT CPU=00:00:03.33 PF=778 IO=296 MEM=277
When SET NOCONTROL=T (the default) is in effect, pressing Ctrl/T does
not cause any statistics to be displayed.
As shown in this example, when you press Ctrl/T, the system displays
the appropriate information. The SET NOCONTROL=T command disables the
Ctrl/T function. Now when you press Ctrl/T, no information is displayed.