This attribute indicates last error found by the decoder. This
attribute has one of the following values:
none: No errors found.
badStepup: Receipt of STEPUP (step up codeword size) codeword
when it would cause C2 (current code word size) to exceed N1
(maximum code word size).
codewordEqC1: Receipt of a codeword, at any time, equal to C1
(next empty dictionary entry).
emptyCodeword: Receipt of a codeword representing an empty
dictionary entry.
reservedCommand: Receipt of a reserved command code.
generalError: Receipt of any other error.
The action taken by V.42bis on detecting an error is provisioned via
TdmaCs/* V42bis.