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HT                                                        CMS Immediate command

Use the HT (Halt typing) Immediate command to suppress all terminal output
generated by any CMS command or your program that is currently executing.  The
format of the HT command is:
+----------+------------------------------------------------------------------+
| HT       |                                                                  |
+----------+------------------------------------------------------------------+

You can issue an Immediate command only after causing an attention interrupt by
pressing the Attention key (or its equivalent).  The command is processed as
soon as it is entered.  It is also executed immediately when stacked in an EXEC
procedure.  Any program execution in progress is suspended until the Immediate
command is processed.


Usage Notes:

1.  Program execution continues.  When the ready message is displayed, normal
    terminal output resumes.  Use the RT command to restore typing or
    displaying.

2.  CMS error messages having a suffix letter of S or T cannot be suppressed.