binmail(1)binmail(1)Namebinmail - send or receive mail among users
/bin/mail [+] [-i] [person...]
/bin/mail [+] [-i] -f file
This is the old version 7 UNIX system mail program. The default com‐
mand is described in and its binary is in the directory The program is
still used to actually deliver a mail message into the users system-
wide mailbox ( ), however, the reading of these messages has been
replaced with the program Do not remove from your system.
The command with no argument prints a user's mail, message-by-message,
in last-in, first-out order; the optional argument + displays the mail
messages in first-in, first-out order. For each message, it reads a
line from the standard input to direct the disposition of the message.
Issue the following commands from the program prompt:
<CR> Go on to next message
d Delete message and go on to the next.
p Print message again.
- Go back to previous message.
s [file...] Save the message in the named files (`mbox'
w [file...] Save the message, without a header, in the named
files (`mbox' default).
m [person...] Mail the message to the named persons (yourself is
EOT (control-D) Put unexamined mail back in the mailbox and stop.
q Same as EOT.
!command Escape to the Shell to do command.
* Print a command summary.
An interrupt normally terminates the command; the mail file is
When persons are named, takes the standard input up to an end-of-file
(or a line with just `.') and adds it to each person's mail file. The
message is preceded by the sender's name and a postmark. Lines that
look like postmarks are prepended with `>'. A person is usually a user
name recognized by To denote a recipient on a remote system, prefix
person by the system name and exclamation mark. For further informa‐
The program sends a message to the screen that there is mail when the
user logs in.
When is used to deliver mail, (usually calls to do this), a mailbox is
created for the user in the directory if it doesn't already exist. The
mailbox is created with the mode 700 so that only its owner can access
it. In addition, the directory has the mode 777 with the sticky bit
set. The mode is 777 so that other mail programs, notably can create
the appropriate lock files to prevent another process from writing to
the mailbox at the same time. The sticky bit set on the directory pre‐
vents one user from unlinking another user's mailbox.
Options-f Displays mail messages contained in the specified
file (next argument) in place of your mailbox file.
-i Notifies mail to continue after interrupts.
Race conditions sometimes result in a failure to remove a lock file.
/etc/passwd to identify sender and locate persons
/usr/spool/mail/* incoming mail for user *
mbox saved mail
/tmp/ma* temp file
/usr/spool/mail/*.lock lock for mail directory
dead.letter unmailable text
See Alsomail(1), uucp(1c), uux(1c), write(1), sendmail(8)binmail(1)