ZDEC (Zero-out Device Error Count) sets the error count field in the
device UCB (UCB$W_ERRCNT) to 0. This program requires CMKRNL privilege,
and executes at elevated IPL to lock the I/O database.

To execute this program a symbol should be set as follows:

      $ ZDEC :== $mydisk:[mydir]ZDEC

To run ZDEC, enter:

      $ ZDEC [/OVERRIDE]  device

where device designates a device. Logical names are accepted and translated.
If the device is allocated (that is, if the owner field in the UCB is 
non-zero), then ZDEC exits without changing the error count, unless the
/OVERRIDE qualifier is used.

ZDEC has been fixed to work under Version 4, and to work properly for
systems that have virtual terminals enabled.

ZDEC has proven useful in zeroing out error counts without re-booting
the operating system. 


Build ZDEC on the system where you'll use it.

If you write tapes, ZDEC can be handy...it lets you clear the
error count, do your write, and check for errors with SHOW ERR
without recalling the initial values.