Legacy configuration MTA option file

The MTA legacy configuration option file is the file.

Each time an MTA program begins running in legacy configuration mode, the MTA option file is read and loaded into memory. This overhead may be avoided by compiling your MTA configuration, in which case the contents of the option file will be incorporated into the compiled configuration. The disadvantage to this, however, is that it means that the configuration must be recompiled and reinstalled whenever a change is made to the option file. See Compiling the MTA configuration for details on compiling your configuration.

The MTA option file is line-oriented, where each line contains the setting for one option. An option setting has the form: option=value where note white space is significant, and white space should not be present before the equal sign. (Indeed, for string values, even trailing white space is significant and -- normally -- preserved as it is meaningful and desired for some options, though as of Messaging Server 7.0, the MTA will attempt some "clean up" of certain option values, such as those for setting file names, and such "clean up" can potentially include removal of extraneous tailing spaces from the option value setting.)

valuemay be either a string, an integer, a floating point value, or a comma-separated list of one such type of value, depending on the option&#x27;s requirements. For further details on value syntax, see Option value syntax in legacy configuration.

Long lines may be continued by ending them with a backslash,.

Comments are allowed. Any line that begins in column one with an exclamation point, semicolon, or shart character, "!", ";", or "#", is considered to be a comment and is ignored (even if the preceding line ended with a backslash, which would normally mean that the line was a continuation). For the MTA option file, the interpretation of the characters "!", ";", and "#" as indicating a comment line is hard-coded; in particular, it is not affected by any setting of the   MTA option (though that option does affect the interpretation of other MTA configuration  files, including other "option files").

Whereas white space on an option setting line is significant, note that blank lines are permitted and ignored in any option file.

Note: This same format is used for various additional MTA  "option files", in addition to "the" MTA option file. That is, some   spam/virus filter package option files,  and in legacy configuration the Dispatcher option file,  Job Controller option file, channel option files,  etc., all use this same sort of format.

See also:
 * MTA options
 * Compiling the MTA configuration
 * Getting option changes to take effect on the MTA
 * Option value syntax in legacy configuration