.\"	$OpenBSD: pkg_add.1,v 1.1 1996/06/04 07:56:04 niklas Exp $
.\"
.\" FreeBSD install - a package for the installation and maintainance
.\" of non-core utilities.
.\"
.\" Redistribution and use in source and binary forms, with or without
.\" modification, are permitted provided that the following conditions
.\" are met:
.\" 1. Redistributions of source code must retain the above copyright
.\"    notice, this list of conditions and the following disclaimer.
.\" 2. Redistributions in binary form must reproduce the above copyright
.\"    notice, this list of conditions and the following disclaimer in the
.\"    documentation and/or other materials provided with the distribution.
.\"
.\" Jordan K. Hubbard
.\"
.\"
.\"     @(#)pkg_add.1
.\"
.Dd November 25, 1994
.Dt pkg_add 1
.Os FreeBSD 2.0
.Sh NAME
.Nm pkg_add
.Nd a utility for installing software package distributions.
.Sh SYNOPSIS
.Nm
.Op Fl vInfRMS
.Op Fl t Ar template
.Op Fl p Ar prefix
.Ar pkg-name [pkg-name ...]
.Sh DESCRIPTION
The
.Nm
command is used to extract packages that have been previously created
with the
.Xr pkg_create 1
command.

.Sh WARNING
.Bf -emphasis
Since the
.Nm
command may execute scripts or programs contained within a package file,
your system may be susceptible to ``trojan horses'' or other subtle
attacks from miscreants who create dangerous package files.
.Pp
You are advised to verify the competence and identity of those who
provide installable package files.  For extra protection, use the
.Fl M
flag to extract the package file, and inspect its contents and scripts
to insure it poses no danger to your system's integrity.  Pay particular
attention to any +INSTALL, +DEINSTALL, +REQUIRE or +MTREE_DIRS files,
and inspect the +CONTENTS file for
.Cm @cwd ,
.Cm @mode 
(check for setuid),
.Cm @dirrm ,
.Cm @exec ,
and
.Cm @unexec
directives, and/or use the
.Xr pkg_info 1
command to examine the package file.
.Ef

.Sh OPTIONS
The following command line arguments are supported.
.Bl -tag -width indent
.It Ar pkg-name [... pkg-name]
The named packages are installed.  A package name of - will cause
.Nm
to read from stdin.
.It Fl v
Turns on verbose output.
.Em "Optional."
.It Fl I
If an installation script exists for a given package, do not execute it.
.Em "Optional."
.It Fl n
Don't actually install a package, just report the steps that
would be taken if it was.
.Em "Optional."
.It Fl R
Do not record the installation of a package.  This means
that you cannot deinstall it later, so only use this option if
you know what you are doing!
.Em "Optional."
.It Fl f
Forces installation to proceed even if prerequisite packages are not
installed or the requirements script fails.
.Em "Optional."
.It Fl p Ar prefix
Sets
.Ar prefix
as the directory in which to extract files from a package.
If a package has set its default directory, it will be overridden
by this flag.  Note that only the first
.Cm @cwd
directive will be replaced, since
.Nm
has no way of knowing which directory settings are relative and
which are absolute.  It is rare, in any case, to see more than one
directory transition made, but when such is the case you
may then wish to look into the use of the
.Cm MASTER
and
.Cm SLAVE
modes (see the
.Fl M
and
.Fl S
options).
.Em "Optional."
.It Fl t Ar template
Use
.Ar template
as the input to 
.Xr mktemp 3 
when creating a ``staging area.''
By default, this is the string
.Pa /var/tmp/instmp.XXXXXX ,
but it may be necessary to override it in the situation where
space in your
.Pa /tmp
directory is limited.  Be sure to leave some number of `X' characters
for
.Xr mktemp 3
to fill in with a unique ID.
.Pp
You can get a performance boost by setting the staging area
.Ar template
to reside on the same disk partition as target directories for package
file installation; often this is
.Pa /usr .
.Em "Optional."
.It Fl M
Run in
.Cm MASTER
mode.  This is a very specialized mode for running
.Nm
and is meant to be run in conjunction with
.Cm SLAVE
mode.  When run in this mode,
.Nm
does no work beyond extracting the package into a temporary staging
area (see the
.Fl t
option), reading in the packing list, and then dumping it (prefaced by
the current staging area) to stdout where it may be filtered by a
program such as
.Xr sed 1 .
When used in conjunction with
.Cm SLAVE
mode, it allows you to make radical changes to the package structure
before acting on its contents.
.It Fl S
Run in
.Cm SLAVE
mode.  This is a very specialized mode for running
.Nm
and is meant to be run in conjunction with
.Cm MASTER
mode.  When run in this mode,
.Nm
expects the release contents to be already extracted and waiting
in the staging area, the location of which is read as a string
from stdin.  The complete packing list is also read from stdin,
and the contents then acted on as normal.
.El
On or more
.Ar pkg-name
arguments may be specified, each being either a file containing the
package (these usually ending with the ``.tgz'' suffix) or a
URL pointing at a file available on an ftp site.  Thus you may
extract files directly from their anonymous ftp locations (e.g.
.Nm
ftp://ftp.freebsd.org/pub/FreeBSD/packages/shells/bash-1.14.4.tgz).
Note:  If you wish to use
.Bf -emphasis
passive mode
.Ef
ftp in such transfers, set
the variable
.Bf -emphasis
FTP_PASSIVE_MODE
.Ef
to some value in your environment.  Otherwise, the more standard
ACTIVE mode may be used.  If
.Nm
consistently fails to fetch a package from a site known to work,
it may be because you have a firewall that demands the usage of
.Bf -emphasis
passive mode
.Ef
ftp.
.Sh TECHNICAL DETAILS
.Nm
is fairly simple.  It extracts each packages' "packing list"
into a special staging directory in /tmp (or $PKG_TMPDIR), parses it,
then runs through the following sequence to fully extract the contents:
.Bl -enum -indent indent
.It
Check if the package is already recorded as installed.  If so,
terminate installation.
.It
Scan all the package dependencies (from
.Cm @pkgdep
directives, see
.Xr pkg_create 1 )
and make sure each one is met. If not, print the missing dependencies and
terminate the installation.
.It
Search for any
.Cm @option
directives which control how the package is added to the system.
At the time of this writing, the only currently implemented option is
.Cm @option extract-in-place
which will cause the package to be extracted direcly into its
prefix directory without moving through a staging area in /tmp.
.It
If
.Cm @option extract-in-place
is enabled, the package is now extracted directly into its
final location, otherwise it is extracted into the staging area.
.It
If the package contains a
.Ar require
file (see 
.Xr pkg_create 1 ),
then execute it with the following arguments:
.Bd -filled -offset indent -compact
.Ar <pkg-name>
.Ar INSTALL
.Ed
where
.Ar <pkg-name>
is the name of the package in question and
.Ar INSTALL
is simply a keyword denoting that this is an installation requirements check.
.It
If an
.Ar install
script exists for the package, it is then executed with the following arguments:
.Bd -filled -offset indent -compact
.Ar <pkg-name>
.Ar PRE-INSTALL 
.Ed
where
.Ar <pkg-name>
is the name of the package in question and
.Ar PRE-INSTALL
is a keyword denoting that this is the preinstallation phase.
.It
If
.Cm @option extract-in-place
is not used, then the packing list (this is the
.Pa +CONTENTS
file) is now used as a guide for moving (or copying, as necessary) files from
the staging area into their final locations.
.It
If the package contains an
.Ar mtreefile
file (see the
.Fl m
option to
.Xr pkg_create 1 ),
then mtree is invoked as
.Bd -filled -offset indent -compact
.Cm mtree
.Fl u 
.Fl f 
.Ar mtreefile
.Fl d
.Fl e 
.Fl p 
.Pa prefix 
.Ed
where
.Pa prefix
is either the prefix specified with the
.Fl p
flag or, if no 
.Fl p
flag was specified, the name of the first directory named by a
.Cm @cwd
directive within this package.
.It
If an
.Ar install
script exists for the package, it is then executed as 
.Bd -filled -offset indent -compact
.Cm <script>
.Ar <pkg-name>
.Ar POST-INSTALL 
.Ed
This all allows you to write a single
.Ar install
script that does both ``before and after'' actions.
.It
After installation is complete, a copy of the packing list,
.Ar deinstall
script, description, and display files are copied into
.Pa /var/db/pkg/<pkg-name>
for subsequent possible use by
.Xr pkg_delete 1 .
Any package dependencies are recorded in the other packages' 
.Pa /var/db/pkg/<other-pkg>/+REQUIRED_BY
file
(if the environment variable PKG_DBDIR is set, this overrides the
.Pa /var/db/pkg/
path shown above).
.It
Finally, the staging area is deleted and the program terminates.
.El
.Pp
All the scripts are called with the environment variable
.Ev PKG_PREFIX
set to the installation prefix (see the
.Fl p
option above).  This allows a package author to write a script
that reliably performs some action on the directory where the package
is installed, even if the user might change it with the
.Fl p
flag to
.Cm pkg_add .
.Sh SEE ALSO
.Xr pkg_info 1 ,
.Xr mktemp 3 ,
.Xr sysconf 3 ,
.Xr mtree 8 ,
.Xr pkg_create 1 ,
.Xr pkg_delete 1 .
.Sh AUTHORS
.Bl -tag -width indent -compact
.It "Jordan Hubbard"
most of the work
.It "John Kohl"
refined it for NetBSD
.El
.Sh BUGS
Hard links between files in a distribution are only preserved if either
(1) the staging area is on the same file system as the target directory of
all the links to the file, or (2) all the links to the file are bracketed by
.Cm @cwd
directives in the contents file, 
.Em and
and the link names are extracted with a single
.Cm tar
command (not split between
invocations due to exec argument-space limitations--this depends on the
value returned by
.Fn sysconf _SC_ARG_MAX ) .
.Pp
Sure to be others.