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Trailing-Edge - PDP-10 Archives - BB-PBQUC-BM_1990 - help/ctrlc.hlp
There are 3 other files named ctrlc.hlp in the archive. Click here to see a list.
CTRL/C

Cancels a command when typed during command entry.

Cancels command execution when typed twice during  command  execution.
(The first ^C does not echo.)

Halts a program and returns to TOPS-20 command level.  Generally, type
two  CTRL/Cs  to  halt a program that is executing; type one CTRL/C to
stop a program that is waiting for input.