all sendmail.cf commands, the
M mail delivery agent command must begin a line.
One typical such command looks like this:
delivery program command line ↓ ↓ Mlocal, P=/bin/mail, F=rlsDFMmnP, S=10, R=20, A=mail -d $u ↑ ↑ ↑ flag sender/recipient rules
M configuration command is composed of six
parts: a symbolic name followed by five delivery agent equates, each
separated from the others by commas. Spaces between the parts are
optional. The specific syntax of the mail delivery agent command is:
Msymname, equate, equate, ...
M always begins the delivery agent
definition, followed by a symbolic name (the
symname) of your choosing and a
comma-separated list of delivery agent equates. Only the
A= delivery agent
equates are required. The others are optional. If the
P= is missing, sendmail will
print and syslog(3) the following error:
configfile: line num: Msymname : P= argument required
A= is missing,
sendmail will print and
syslog(3) the following error:
configfile: line num: Msymname : A= argument required
In both error messages, configfile is the full pathname of the sendmail configuration file, num is the line number in that file where the error was found, and symname is the delivery agent definition that omitted the required piece of information.
The comma following the symbolic name is optional. As long as a space follows the symbolic name, sendmail parses it correctly. The comma should always be included for improved clarity, ...