NAME

     mail.local — store mail in a mailbox

SYNOPSIS

     mail.local [-Ll] [-f from] user ...

DESCRIPTION

     mail.local reads the standard input up to an end-of-file and appends it to each user's mail
     file.  The user must be a valid user name.

     The options are as follows:

     -f from
             Specify the sender's name.

     -L      Don't create a username.lock file while locking the spool.

     -l      For compatibility, request that files named username.lock be used for locking.
             (This is the default behavior.)

     Individual mail messages in the mailbox are delimited by an empty line followed by a line
     beginning with the string “From ”.  A line containing the string “From ”, the sender's name
     and a timestamp is prepended to each delivered mail message.  A blank line is appended to
     each message.  A greater-than character (‘>’) is prepended to any line in the message which
     could be mistaken for a “From ” delimiter line.

     Significant efforts have been made to ensure that mail.local acts as securely as possible if
     the spool directory is mode 1777 or 755.  The default of mode 755 is more secure, but it
     prevents mail clients from using username.lock style locking.  The use of 1777 is more
     flexible in an NFS shared-spool environment, so many sites use it.  However, it does carry
     some risks, such as attackers filling the spool disk.  Some of these problems may be
     alleviated by making the spool a separate filesystem, and placing quotas on it.  The use of
     any mode other than 1777 and 755 for the spool directory is recommended against but may work
     properly.

     The mailbox is always locked using flock(2) while mail is appended.  Unless the -L flag is
     specified, a username.lock file is also used.

     If the biff(1) service is returned by getservbyname(3), the biff server is notified of
     delivered mail.

ENVIRONMENT

     TZ      Used to set the appropriate time zone on the timestamp.

FILES

     /tmp/local.XXXXXXXXXX  temporary files
     /var/mail/user         user's mailbox directory

EXIT STATUS

     The mail.local utility exits 0 on success, and >0 if an error occurs.

SEE ALSO

     biff(1), mail(1), flock(2), getservbyname(3), comsat(8), smtpd(8)

HISTORY

     A superset of mail.local (handling mailbox reading as well as mail delivery) appeared in
     Version 7 AT&T UNIX as the program mail(1).

BUGS

     Using quotas in /var/mail can be problematic if using sendmail(8) as an MTA, since it asks
     mail.local to deliver a message to multiple recipients if possible.  This causes problems in
     a quota environment since a message may be delivered to some users but not others due to
     disk quotas.  Even though the message was delivered to some of the recipients, mail.local
     will exit with an exit code > 0, causing sendmail(8) to attempt redelivery later.  That
     means that some users will keep getting the same message every time sendmail(8) runs its
     queue.  This problem does not exist for smtpd(8) users.

     If you are running sendmail(8) and have disk quotas on /var/mail it is imperative that you
     unset the “m” mailer flag for the ‘local’ mailer.  To do this, locate the line beginning
     with “Mlocal” in /etc/mail/sendmail.cf and remove the “m” from the flags section, denoted by
     “F=”.  Alternately, you can override the default mailer flags by adding the line:

           define(`LOCAL_MAILER_FLAGS', `rn9S')dnl

     to your “.mc” file (this is the source file that is used to generate /etc/mail/sendmail.cf).