Beginning with version 8.7 sendmail, configuration-file options may use multicharacter option names. Prior to version 8.7, only single characters were allowed. We describe the old form first, then the new.
The old form for an option command in the sendmail.cf file is
argumentprior to V8.7
Like all configuration commands,
the uppercase letter
O must begin the line.
It is immediately followed (with no intervening
space) by another single
letter, which selects a specific option.
Uppercase letters are distinct from lowercase for single-character
option names (that is,
X is different from
Depending on the option
argument may be required.
There must be no intervening space between the single-character option
name and its argument.
Beginning with version 8.7, option names may be single-character or multicharacter. A space is used to differentiate between single-character and multicharacter (long) names:
O LongName=argument beginning with V8.7 a space (not a tab)
O configuration command is followed by a space (not
a tab), everything following that space is taken as the declaration
of a multicharacter option.
Unlike single-letter option names, multicharacter names are interpreted by
sendmail without regard to case. Therefore the following three examples all
produce the same effect:
O QueueDirectory=/var/tmp O queuedirectory=/var/tmp O QuEuEdIrEcToRy=/var/tmp
There may be optional space (not tab) characters surrounding the
O QueueDirectory = /var/tmp spaces, not tabs
Multicharacter names in the configuration file must not be abbreviated or expressed in shorthand:
O QueueDirectory=/var/spool/mqueue good O QueueDir=/var/spool/mqueue bad
Failure to use the full multicharacter name will
cause sendmail to print spurious warnings every time it is run.
The possible warnings are listed in Section 18.104.22.168, "Multicharacter name shorthand".
Multicharacter names are beneficial because they allow option names to have
For example, the multicharacter name
ForwardPath, which lists the
default path for ~/.forward files, is much more recognizable
than the single-character name