As any mailutils-based program, wyslij-po uses a special
logical entity called mailer in order to actually submit
messages. By default it uses the MTA facilities of the machine it runs
on, so you usually don’t have to explicitly specify which mailer to
use. There may, however, be some cases when this becomes necessary.
This section describes how to do so.
A mailer is specified by its URL. An URL
begins with a protocol specification. Two protocol specifications are
currently supported: ‘sendmail’ and ‘smtp’. The former
means to use a sendmail-compatible program to send mails.
Such a program must be able to read mail from its standard input and
must support the following options:
Do not treat ’.’ as message terminator.
Use addr as the address of the sender.
Get recipient addresses from the message.
These conditions are met by most existing MTA programs, such
as exim or postfix (to say nothing of
sendmail itself).
Following the protocol specification is the mailer location, which is separated from it with a colon. For the ‘sendmail’ protocol, the mailer location sets the full file name of the sendmail-compatible MTA binary, for example:
sendmail:/usr/sbin/sendmail
A special form of sendmail URL, consisting of protocol
specification only (‘sendmail:’) is also allowed. It means
“use the sendmail binary from the _PATH_SENDMAIL
macro in your /usr/include/paths.h file”. This is the default
mailer.
The ‘smtp’ protocol means to use an SMTP server directly. In this case the mailer location consists of two slashes, followed by the IP address or host name of the SMTP server, and, optionally, the port number. If the port number is present, it is separated from the rest of URL by a colon. For example:
smtp://remote.server.net smtp://remote.server.net:24
The URL of the mailer to use is set using --mailer (-M) command line option. For example:
$ wyslij-po --mailer=smtp://127.0.0.1 pl.po
An alternative way is to set it in the configuration file, using
mailer statement (see Mailer Statement in GNU Mailutils Manual).
As an example of a rather extreme approach, here is how to deliver mails directly to the TP mail server:
$ wyslij-po --mailer=smtp://mail.vrijschrift.org …