SYSTAT mnemonics:

Task states:
abo - marked for abort
acp - ancillary control processor
ast - AST in progress
caf - dynamic checkpoint space allocation failure
cal - checkpoint space allocated in task image
ckd - checkpointing is disabled
ckp - being checkpointed
ckr - ckeckpointing requested
cli - command language interpreter
dst - AST recognition disabled
fxd - fixed in memory
hlt - halted
mcr - invoked by external MCR function
msg - abort message being output by TKTN
ncp - not checkpointable
net - uses revised network protocol
nrp - mapped to non-resident partition
nsd - cannot be sent to
out - out of memory
prv - privileged
rdn - I/O is being run down
rem - remove on exit
rov - memory resident overlays
rst - restricted
slv - slave
spn - suspended
stp - stopped
tio - engaged in terminal I/O
wfr - waiting for an event flag

TTY characteristics:
at - processing an AT. command
ti - terminal input wait
to - terminal output wait
cts - control S wait

$ before user name indicates a privileged user
# indicates the user is not logged in
Default UIC is only shown if different from protection UIC