Unfortunately, this provides little diagnostic information to the client.
How is the client to know whether the problem is that the file doesn't
exist, or there's no route to host, or DNS hostname cannot be resolved,
etc.? One solution would be to tuck a descriptive error message into
"job-state-message", but that violates this paragraph from MOD section
4.3.9:
Note: the value SHOULD NOT contain additional information not
contained in the values of the "job-state" and "job-states-reasons"
attributes, such as interpreter error information. Otherwise, application
programs might attempt to parse the (localized text). For such additional
information such as interpreter errors for application program consumption,
a new attribute with keyword values, needs to be developed and registered.
I suppose we could generate a new attribute with keyword values such as
'no-route-to-host'
'cannot-resolve-hostname'
'connection-refused'
'connection-timed-out'
'cannot-bind-to-port'
'connection-reset-by-peer'
'http-404'
'http-400'
'http-500'
'ftp-xxx'
'ftp-yyy'
etc...
-Carl