+.P
+Like other MTAs, Exim replaces Sendmail, and is normally called by user agents
+(MUAs) using the path \\fI/usr/sbin/sendmail\\fP when they submit messages for
+delivery (some operating systems use \\fI/usr/lib/sendmail\\fP). This path is
+normally set up as a symbolic link to the Exim binary. It may also be used by
+boot scripts to start the Exim daemon. Many of Exim's command line options are
+compatible with Sendmail so that it can act as a drop-in replacement.
+.
+.SH "DEFAULT ACTION"
+.rs
+.sp
+If no options are present that require a specific action (such as starting the
+daemon or a queue runner, testing an address, receiving a message in a specific
+format, or listing the queue), and there are no arguments on the command line,
+Exim outputs a brief message about itself and exits.
+.sp
+However, if there is at least one command line argument, \\fB-bm\\fR (accept a
+local message on the standard input, with the arguments specifying the
+recipients) is assumed. Thus, for example, if Exim is installed in
+\\fI/usr/sbin\\fP, you can send a message from the command line like this:
+.sp
+ /usr/sbin/exim -i <recipient-address(es)>
+ <message content, including all the header lines>
+ CTRL-D
+.sp
+The \\fB-i\\fP option prevents a line containing just a dot from terminating
+the message. Only an end-of-file (generated by typing CTRL-D if the input is
+from a terminal) does so.
+.
+.SH "SETTING OPTIONS BY PROGRAM NAME"