xsend(1) [v7 man page]
XSEND, XGET, ENROLL(1) General Commands Manual XSEND, XGET, ENROLL(1) NAME
xsend, xget, enroll - secret mail SYNOPSIS
xsend person xget enroll DESCRIPTION
These commands implement a secure communication channel; it is like mail(1), but no one can read the messages except the intended recipi- ent. The method embodies a public-key cryptosystem using knapsacks. To receive messages, use enroll; it asks you for a password that you must subsequently quote in order to receive secret mail. To receive secret mail, use xget. It asks for your password, then gives you the messages. To send secret mail, use xsend in the same manner as the ordinary mail command. (However, it will accept only one target). A message announcing the receipt of secret mail is also sent by ordinary mail. FILES
/usr/spool/secretmail/*.key: keys /usr/spool/secretmail/*.[0-9]: messages SEE ALSO
mail (1) BUGS
It should be integrated with ordinary mail. The announcement of secret mail makes traffic analysis possible. XSEND, XGET, ENROLL(1)
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BINMAIL(1) General Commands Manual BINMAIL(1) NAME
binmail - send or receive mail among users SYNOPSIS
/bin/mail [ + ] [ -i ] [ person ] ... /bin/mail [ + ] [ -i ] -f file DESCRIPTION
Note: This is the old version 7 UNIX system mail program. The default mail command is described in Mail(1), and its binary is in the directory /usr/ucb. mail with no argument prints a user's mail, message-by-message, in last-in, first-out order; the optional argument + displays the mail mes- sages in first-in, first-out order. For each message, it reads a line from the standard input to direct disposition of the message. newline 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' default). 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 default). 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 mail command; the mail file is unchanged. The optional argument -i tells mail to continue after interrupts. When persons are named, mail 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 login(1). To denote a recipient on a remote system, prefix person by the system name and exclamation mark (see uucp(1C)). The -f option causes the named file, for example, `mbox', to be printed as if it were the mail file. When a user logs in he is informed of the presence of mail. FILES
/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 ALSO
Mail(1), write(1), uucp(1C), uux(1C), xsend(1), sendmail(8) BUGS
Race conditions sometimes result in a failure to remove a lock file. Normally anybody can read your mail, unless it is sent by xsend(1). An installation can overcome this by making mail a set-user-id command that owns the mail directory. 7th Edition April 29, 1985 BINMAIL(1)