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.\" Copyright (c) 2003 Mike Barcroft <mike@FreeBSD.org>
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.Dd May 27, 2009
.Dt JEXEC 8
.Os
.Sh NAME
.Nm jexec
.Nd "execute a command inside an existing jail"
.Sh SYNOPSIS
.Nm
.Op Fl u Ar username | Fl U Ar username
.Ar jail command ...
.Sh DESCRIPTION
The
.Nm
utility executes
.Ar command
inside the
.Ar jail
identified by its jid or name.
.Pp
The following options are available:
.Bl -tag -width indent
.It Fl u Ar username
The user name from host environment as whom the
.Ar command
should run.
.It Fl U Ar username
The user name from jailed environment as whom the
.Ar command
should run.
.El
.Sh SEE ALSO
.Xr jail_attach 2 ,
.Xr jail 8 ,
.Xr jls 8
.Sh HISTORY
The
.Nm
utility was added in
.Fx 5.1 .
.Sh BUGS
If the jail is not identified by
.Ar jid
there is a possible race in between the lookup of the jail
and executing the command inside the jail.
Giving a
.Ar jid
has a similar race as another process can stop the jail and
start another one after the user looked up the
.Ar jid .