Useful Tables

There are two tables of interest for handling the sendmail command line:

  • Table 15-1 shows the alternate names that sendmail will run under and the effect of each.

  • Table 15-2 shows the command-line switches used by sendmail and describes the effect of each.

Alternative argv[0] Names

The sendmail program can exist in any of several places, depending on the version of the operating system you are running. Usually, it is located in the /usr/sbin directory and is called sendmail,[21] but it can also be located in the /etc, /usr/lib, /usr/libexec, or /usr/etc directories. The location of the sendmail program can be found by examining the /etc/rc files for BSD Unix or the /etc/init.d files for Sys V Unix (§1.6.11[3ed]). Also, on some BSD-derived systems, the mailwrapper program and its /etc/mail/mailer.conf file define where sendmail is located.

In addition to the name sendmail, other names (in other directories) can exist that alter the behavior of sendmail. Those alternative names are usually symbolic links to /usr/sbin/sendmail. On some systems, they can be hard links, and in rare cases, you might actually find them to be copies. The complete list of other names is shown in Table 15-1.

Table 15-1. Alternative names for sendmail


sendmail text reference

Mode of operation



Print persistent host status (V8.8 and later)



Print the queue contents



Rebuild the aliases file


15.1.4[3ed] ...

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