.\"	$NetBSD: biff.1,v 1.11 2016/12/20 08:21:32 abhinav Exp $
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.\"     @(#)biff.1	8.1 (Berkeley) 6/6/93
.\"
.Dd December 20, 2016
.Dt BIFF 1
.Os
.Sh NAME
.Nm biff
.Nd be notified if mail arrives and who it is from
.Sh SYNOPSIS
.Nm
.Op Cm n | y
.Sh DESCRIPTION
.Nm
informs the system whether you want to be notified when mail arrives
during the current terminal session.
.Pp
Options supported by
.Nm :
.Bl -tag -width 4n
.It Cm n
Disables notification.
.It Cm y
Enables notification.
.El
.Pp
When mail notification is enabled, the header and first few lines of
the message will be printed on your screen whenever mail arrives.
A
.Dq Li biff y
command is often included in the file
.Pa \&.login
or
.Pa \&.profile
to be executed at each login.
.Pp
When no arguments are present,
.Nm
displays the current notification status to the standard output.
.Pp
.Nm
operates asynchronously.
For synchronous notification use the
.Ar MAIL
variable of
.Xr sh 1
or the
.Ar mail
variable of
.Xr csh 1 .
.Sh EXIT STATUS
The
.Nm
utility exits with one of the following values:
.Bl -tag -width indent
.It 0
Notification was enabled at the time of invocation.
.It 1
Notification was disabled at the time of invocation.
.It >1
An error occurred.
.El
.Sh SEE ALSO
.Xr csh 1 ,
.Xr from 1 ,
.Xr mail 1 ,
.Xr sh 1 ,
.Xr comsat 8
.Sh HISTORY
The
.Nm
command appeared in
.Bx 4.0 .