xref: /netbsd-src/lib/libutil/ttyaction.3 (revision f96996de73923c47404ad0d08162b451791959de)

.\" $NetBSD: ttyaction.3,v 1.16 2021/03/21 23:29:36 mrg Exp $
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.\" This code is derived from software contributed to The NetBSD Foundation
.\" by Gordon W. Ross.
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.Dd May 4, 2010
.Dt TTYACTION 3
.Os
.Sh NAME
.Nm ttyaction
.Nd ttyaction utility function
.Sh LIBRARY
.Lb libutil
.Sh SYNOPSIS
.In util.h
.Ft int
.Fn ttyaction "char *ttyname" "char *action" "char *username"
.Sh DESCRIPTION
The
.Fn ttyaction
function is used by
.Xr login 1 ,
.Xr getty 8 ,
.Xr telnetd 8
and
.Xr rlogind 8
to execute site-specific commands
when a login session begins and ends.
.Pp
The
.Fn ttyaction
function scans the
.Pa /etc/ttyaction
file for any records that match the current
.Fa ttyname
and
.Fa action
parameters, and for each matching record,
runs the shell command shown in that record.
The record format is described in
.Xr ttyaction 5 .
The parameter
.Fa username
is the name of the new owner of the
.Fa ttyname
device.
Note that the
.Fa ttyname
parameter may be passed as a fully qualified pathname, and the
.Fn ttyaction
function will skip the leading "/dev/" part of the string.
(This is a convenience for login and getty.)
.Sh RETURN VALUES
.Fn ttyaction
returns the status of the last command it executed,
or zero if no matching commands were found.
.Sh FILES
.Bl -tag -width /etc/ttyaction -compact
.It Pa /dev/\(**
.It Pa /etc/ttyaction
.El
.Sh SEE ALSO
.Xr ttyaction 5
.Sh HISTORY
The
.Fn ttyaction
function appeared in
.Nx 1.3 .
.Sh AUTHORS
.An Gordon W. Ross
.Aq gwr@NetBSD.org ,
.An Chris G. Demetriou
.Aq cgd@NetBSD.org ,
.An Ty Sarna
.Aq tsarna@NetBSD.org .
.Sh BUGS
There should be some
.Em other
mechanism to allow selection of different access control policies
on a per-line basis.
It has been suggested that the same
.Fn ttyaction
mechanism should also be used for determining access control, but
it was decided (after much discussion) that
.Fn ttyaction
should only describe actions to be performed
.Em after
the system has decided to change the ownership of some tty.
Access control policies will be handled by a separate mechanism.