Re: [exim] Disk failure => 5xx error code

Thanks for the prompt reply Philip. First, I've had another chat with
our postmaster and it seems that it wasn't a "No such user" type error
but:

554 SMTP service not available

Sorry about the confusion, clearly it wasn't getpwnam but was presumably
either a hosts_ctl() or verify_check_host() problem.

Obviously this raises a potentially tricky question of whether this
should return 5xx or 4xx but could we try the following: zero errno
before the check and if the check fails test errno for a list of values
that must mean "something is wrong" (EIO, EMFILE, ENFILE, ENOMEM, ENOSPC
and maybe a few others). A system/process error errno value could return
451, others the current default of 554. This is easy to do and has to be
an unambiguous win.

Better still, one could easily argue that smtp_printf should be modified
to do that since if errno has been set to one of those values then
there's a system problem and an alternate host should be tried. If
you're busy I'll happily throw something together.

Thanks again.

John