K N O W N B U G S I N S E N D M A I L
The following are bugs or deficiencies in sendmail that I am aware of
but which have not been fixed in the current release. You probably
want to get the most up to date version of this from FTP.CS.Berkeley.EDU
in /ucb/sendmail/KNOWNBUGS. For descriptions of bugs that have been
fixed, see the file RELEASE_NOTES (in the root directory of the sendmail
This list is not guaranteed to be complete.
* Null bytes are not handled properly.
Sendmail should handle full binary data. As it stands, it handles
any value from 0x01-0xFF in the body and 0x01-0x80 and 0xA0-0xFF in
the header. Notably missing is 0x00, which would require a major
restructuring of the code -- for example, almost no C library support
could be used to handle strings. Fixed (for the message body only)
* Duplicate error messages.
Sometimes identical, duplicate error messages can be generated. As
near as I can tell, this is rare and relatively innocuous.
* No "exposed users" in "nullrelay" configuration.
The "nullrelay" configuration hides all addresses behind the mail
hub name. Some sites might prefer to expose some names such as
root. This information is always available in Received: lines.
* $c (hop count) macro improperly set.
The $c macro is supposed to contain the current hop count, for use
when calling a mailer. This macro is initialized too early, and
is always zero (or the value of the -c command line flag, if any).
This macro will probably be removed entirely in a future release;
I don't believe there are any mailers left that require it.
* If you EXPN a list or user that has a program mailer, the output of
EXPN will include ``@local.host.name''. You can't actually mail to
this address. It's not clear what the right behaviour is in this
* REDIRECT aliases don't work with `n' option.
If you have option `n' set when you use newaliases and have
REDIRECT addresses in your aliases file, you'll get the error
messages during the newaliases instead of when email is sent to
the address in question. The workaround is to turn off the `n'
* MX records that point at non-existent hosts work strangly.
Consider the DNS records:
(note that there is no A record for hostB). If hostA is down,
an attempt to send to hostH gives "host unknown" -- that is, it
reflects out the status on the last host it tries, which in this
case is hostB, which is unknown. It probably ought to eliminate
hostB early in processing.
* NAME environment variables with commas and unbalanced quotes break.
If you define your NAME environment variable to have a comma
(e.g., ``Lastname, Firstname''), and you are using the $q definition
that uses ``name <address>'' format, sendmail treats the first and
last names as two addresses, thus producing a bogus From line. You
can work around this by changing the $q definition to use
If you have an unbalanced double quote (e.g., ``Firstname"Lastname'')
the auto-quoting algorithm breaks.
* \231 considered harmful.
Header addresses that have the \231 character (and possibly others
in the range \201 - \237) behave in odd and usually unexpected ways.
* DEC Alphas (OSF/1 1.3) sometimes time out on sending mail.
I have one report that DEC Alphas acting as SMTP clients sometimes
will apparently not see the "250 OK" message in response to the
dot that indicates the end of the message. This only happens if
the message is run from the queue -- if it gets through on first
try, everything is fine. I have been unable to reproduce this
* accept() problem on SVR4.
Apparently, the sendmail daemon loop (doing accept()s on the network)
can get into a wierd state on SVR4; it starts logging ``SYSERR:
getrequests: accept: Protocol Error''. The workaround is to kill
and restart the sendmail daemon. We don't have an SVR4 system at
Berkeley that carries more than token mail load, so I can't validate
this. It is likely to be a glitch in the sockets emulation, since
"Protocol Error" is not possible error code with Berkeley TCP/IP.
I've also had someone report the message ``sendmail: accept:
SIOCGPGRP failed errno 22'' on an SVR4 system. This message is
not in the sendmail source code, so I assume it is also a bug
in the sockets emulation. (Errno 22 is EINVAL "Invalid Argument"
on all the systems I have available, including Solaris 2.x.)
* Sending user deletion not done properly in :include: lists.
If you don't have the "m" (me too) option set, then a person
sending to a list that contains themselves should not get a copy
of the message. However, if that list points to a :include: file
that has one address per line, this will break, and the sender
will always get a copy of their own message, just as though the
You can eliminate this by adding commas at the end of each line
* Excessive mailing list nesting can run out of file descriptors.
If you have a mailing list that includes lots of other mailing
lists, each of which has a separate owner, you can run out of
file descriptors. Each mailing list with a separate owner uses
one open file descriptor (prior to 8.6.6 it was three open
file descriptors per list). This is particularly egregious if
you have your connection cache set to be large.
(Version 8.19, last updated %G%)
projects / unix-history / blob