extsmail releases


extsmail is released under a BSD / MIT style licence.

Available as pre-built packages:

Formal releases:

  • extsmail 2.4 (2020-01-31) (66K)
    • Fix a bug whereby a failure in executing a child process could cause an individual mail to be sent more than once and/or an unbounded number of child processes to persist indefinitely.
  • extsmail 2.3 (2019-10-14) (66K)
    • Have autoconf decide whether to use lex/yacc or flex/bison.
    • Add pledge support for extsmail and extsmaild on OS's that support it.
    • If a child process fails, but doesn't print anything to stderr, then format the result more nicely.
    • Build correctly on Linux distributions that identify as GNU rather than Linux.
    • extsmaild -v now prints extsmail's version number.
  • extsmail 2.2 (2018-11-30) (66K)
    • Suggest using -t with sendmail in examples (some sendmail clones require this switch).
    • Use -z,now when linking.
    • Fix two minor compiler warnings.

Previous releases are available.

Development of extsmail uses git. If you wish to contribute to extsmail, it is recommended that you work with a check-out of the repository. You can get a copy with the following command:

$ git clone git://github.com/ltratt/extsmail.git
You can also view extsmail's online git repository. Patches are always gratefully received.

60 second install instructions

If you don't like reading manuals, most per-user configurations of extsmail can be accommodated with the following commands:
$ ./configure
$ make
$ make install
$ mkdir -m 700 -p ~/.extsmail/spool_dir
$ echo spool_dir = \"~/.extsmail/spool_dir\" > ~/.extsmail/conf
If you want to send e-mail to another machine via ssh, you then need to create the file ~/.extsmail/externals and put in the following configuration:
group {
    external mymachine {
        sendmail = "/usr/bin/ssh -q -C -l user mymachine.net /usr/sbin/sendmail -t"
where mymachine is a human-friendly name given to an external (it does not effect processing), and user is your username on the remote machine mymachine.net.

If instead you want to use msmtp, your ~/.extsmail/externals file will look as follows:

group {
    external mymachine {
        sendmail = "/usr/local/bin/msmtp -a myaccount"
where mymachine is a human-friendly name given to an external (it does not effect processing), and myaccount is the msmtp account you want to send mail as.

You can then run extsmaild either as a batch mode process (e.g. from cron) or, generally better, as a daemon, started from a start-up script (e.g. ~/.xsession):

extsmaild -m daemon

You then need to configure whatever programs you're using to send mail to use extsmail instead of your normal sendmail binary. extsmaild will use syslog for logging (typically logging into /var/log/maillog).

And with that you're done. If you want to do something more complex you'll need to read the detailed instructions (extsmail comes with complete man page documentation), but the above works perfectly well for the majority of cases.


extsmail is a C application. It should be trivially portable to any POSIX compliant operating system. It can be installed as follows:
$ ./configure
$ make
$ make install
Please note that if, and only if, you are building from the git repository you will first need to execute make -f Makefile.bootstrap to build the configure script.