Command-Line Switches

Command-line switches are command-line arguments that begin with a - character, and precede the list of recipients (if any). The forms for command-line switches, where X is a single letter, are:

-XBoolean switch
-Xargswitch with argument

All switches are single letters. The complete list is shown in Table 6-2.

Table 6-2. Command-line switches






-A on page 231

V8.12 and later

Specify versus


-B on page 232

V8.1 and later

Specify message body type.


-b on page 233

All versions

Set operating mode.


-ba on page 233

Not V8.1- V8.6

Use ARPAnet/Grey Book protocols.


-bD on page 233

V8.8 and later

Run as a daemon, but don’t fork.


-bd on page 234

All versions

Run as a daemon.


-bH on page 234

V8.8 and later

Purge persistent host status.


-bh on page 235

V8.8 and later

Print persistent host status.


Rebuild the Alias Database on page 478

All versions

Initialize alias database.


-bm on page 235

All versions

Be a mail sender (the default).


-bP on page 236

V8.12 and later

Print number of messages in the queue.


Printing the Queue on page 422

All versions

Print the queue.


-bs on page 236

All versions

Run SMTP on standard input.


Chapter 8 on page 299

All versions

Rule-testing mode.


-bv on page 237

All versions

Verify: don’t collect or deliver.


-bz on page 238

Not V8

Freeze the configuration file.


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