1.\" Copyright (c) 1980, 1990, 1993 2.\" The Regents of the University of California. All rights reserved. 3.\" 4.\" Redistribution and use in source and binary forms, with or without 5.\" modification, are permitted provided that the following conditions 6.\" are met: 7.\" 1. Redistributions of source code must retain the above copyright 8.\" notice, this list of conditions and the following disclaimer. 9.\" 2. Redistributions in binary form must reproduce the above copyright 10.\" notice, this list of conditions and the following disclaimer in the 11.\" documentation and/or other materials provided with the distribution. 12.\" 3. Neither the name of the University nor the names of its contributors 13.\" may be used to endorse or promote products derived from this software 14.\" without specific prior written permission. 15.\" 16.\" THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND 17.\" ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 18.\" IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 19.\" ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE 20.\" FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 21.\" DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 22.\" OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 23.\" HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 24.\" LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 25.\" OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 26.\" SUCH DAMAGE. 27.\" 28.Dd April 28, 2013 29.Dt BIFF 1 30.Os 31.Sh NAME 32.Nm biff 33.Nd "be notified if mail arrives and who it is from" 34.Sh SYNOPSIS 35.Nm 36.Op Cm n | y | b 37.Sh DESCRIPTION 38The 39.Nm 40utility informs the system whether you want to be notified on your terminal 41when mail arrives. 42.Pp 43Affected is the first terminal associated with the standard input, 44standard output or standard error file descriptor, in that order. 45Thus, it is possible to use the redirection facilities of a shell to 46toggle the notification for other terminals than the one 47.Nm 48runs on. 49.Pp 50The following options are available: 51.Bl -tag -width indent 52.It Cm n 53Disable notification. 54.It Cm y 55Enable header notification. 56.It Cm b 57Enable bell notification. 58.El 59.Pp 60When header notification is enabled, the header and first few lines of 61the message will be printed on your terminal whenever mail arrives. 62A 63.Dq "biff y" 64command is often included in the file 65.Pa .login 66or 67.Pa .profile 68to be executed at each login. 69.Pp 70When bell notification is enabled, only two bell characters 71.Tn ( ASCII 72\\007) 73will be printed on your terminal whenever mail arrives. 74.Pp 75If no arguments are given, 76.Nm 77displays the present notification status of the terminal to the 78standard output. 79.Pp 80The 81.Nm 82utility operates asynchronously. 83For synchronous notification use the 84.Ev MAIL 85variable of 86.Xr sh 1 87or the 88.Va mail 89variable of 90.Xr csh 1 . 91.Sh EXIT STATUS 92The 93.Nm 94utility exits with one of the following values: 95.Bl -tag -width indent 96.It 0 97Notification was enabled at the time of invocation. 98.It 1 99Notification was disabled at the time of invocation. 100.It >1 101An error occurred. 102.El 103.Sh COMPATIBILITY 104Previous versions of the 105.Nm 106utility affected the terminal attached to standard error without first 107trying the standard input or output devices. 108.Sh SEE ALSO 109.Xr csh 1 , 110.Xr mail 1 , 111.Xr sh 1 , 112.Xr comsat 8 113.Sh HISTORY 114The 115.Nm 116command appeared in 117.Bx 4.0 . 118It was named after the dog of Heidi Stettner. 119He died 120in August 1993, at 15. 121