.\"	$OpenBSD: pkg_add.1,v 1.30 2003/03/07 06:30:38 david Exp $
.\"
.\" FreeBSD install - a package for the installation and maintenance
.\" 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
.Sh NAME
.Nm pkg_add
.Nd install software package distributions
.Sh SYNOPSIS
.Nm pkg_add
.Op Fl vInfRMS
.Op Fl t Ar template
.Op Fl p Ar prefix
.Ar pkg-name Op Ar ...
.Sh DESCRIPTION
The
.Nm
command is used to extract packages that have been previously created
with the
.Xr pkg_create 1
command.
Selected packages containing pre-compiled applications from the
.Pa /usr/ports
tree can be found on the
.Ox
FTP site or on the official
.Ox
CD.
These packages are provided as a convenience for quickly installing software
that would otherwise need to be built manually.
.Bd -filled -offset indent
.Em Note :
System distribution files, e.g. base28.tgz, comp28.tgz, etc., are
.Em not
packages and may not be installed using
.Nm pkg_add .
.Ed
.Pp
Package names may be specified as filenames (which normally consist of the
package name itself plus the
.Dq .tgz ,
.Dq .tar.gz ,
or
.Dq .tar
suffix) or an FTP location in the form of an URL.
For example, the following is valid:
.Pp
.Ic pkg_add -v ftp://ftp.openbsd.org/pub/OpenBSD/2.7/packages/i386/m4-1.4.tgz
.Pp
If the given package names are not found in the current working directory,
.Nm
will search for them in each directory named by the
.Ev PKG_PATH
environment variable.
Specifying
.Ql -
as a package name causes
.Nm
to read from the standard input.
.Pp
Alternatively, it is possible to add packages interactively from within
the ftp client.
For example, the following works:
.Bd -literal
	$ ftp ftp://ftp.openbsd.org/pub/OpenBSD/2.7/packages/i386
	250 CWD command successful
	ftp> ls m*
	227 Entering Passive Mode (129,128,5,191,164,73)
	150 Opening ASCII mode data connection for m*.
	m4-1.4.tgz
	metamail-2.7.tgz
	mh-6.8.4.tgz
	mm-1.0.12.tgz
	mpeg_lib-1.2.1.tgz
	mpeg_play-2.4.tgz
	mpg123-0.59q.tgz
	mutt-0.95.7i.tgz
	226 Transfer complete.
	ftp> get m4-1.4.tgz "|pkg_add -v -"
.Ed
.Pp
.Sy Warning:
Since the
.Nm
command may execute scripts or programs contained within a package file,
your system may be susceptible to
.Dq trojan horses
or other subtle attacks from miscreants who create dangerous packages.
Be sure the specified package(s) are from trusted sources.
.Pp
The options are as follows:
.Bl -tag -width Ds
.It Fl v
Turn on verbose output.
.It Fl I
If an installation script exists for a given package, do not execute it.
.It Fl n
Don't actually install a package, just report the steps that
would be taken if it was.
.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!
.It Fl f
Force installation to proceed even if prerequisite packages are not
installed or the requirements script fails.
Although
.Nm
will still try to find and auto-install missing prerequisite packages,
a failure to find one will not be fatal.
.It Fl p Ar prefix
Set
.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 does happen and you wish
to have control over
.Em all
directory transitions, then you may then wish to look into the use of
.Cm MASTER
and
.Cm SLAVE
modes (see the
.Fl M
and
.Fl S
options).
.It Fl t Ar template
Use
.Ar template
as the input to
.Xr mkdtemp 3
when creating a
.Dq staging area .
By default, this is the string
.Pa /var/tmp/instmp.XXXXXX ,
but it may be necessary to override it (see CAVEATS).
Be sure to leave some number of
.Dq X
characters for
.Xr mkdtemp 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 .
.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 the standard output 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 the standard input.
The complete packing list is also read from stdin,
and the contents then acted on as normal.
.El
.Pp
By default, when adding packages via FTP, the
.Xr ftp 1
program operates in
.Dq passive
mode.
If you wish to use active mode instead, set the
.Ev FTPMODE
environment variable to
.Qq active .
If
.Nm
consistently fails to fetch a package from a site known to work,
it may be because the site does not support
passive mode ftp correctly.
This is very rare since
.Nm
will try active mode ftp if the server refuses a passive mode
connection.
.Ss Technical details
.Nm
extracts each package's
.Dq packing list
into a special staging directory in
.Pa /var/tmp
(or
.Ev PKG_TMPDIR
if set - see CAVEATS section)
and then runs through the following sequence to fully extract the contents
of the package:
.Bl -enum -indent indent
.It
A check is made to determine if the package is already recorded as installed.
If it is,
installation is terminated.
.It
A check is made to determine if the package conflicts (from
.Cm @pkgcfl
directives, see
.Xr pkg_create 1 )
with an already recorded as installed package.
If it is, installation is terminated.
.It
All package dependencies (from
.Cm @pkgdep
directives, see
.Xr pkg_create 1 )
are read from the packing list.
If any of these required packages are not currently installed,
an attempt is made to find and install it;
if the missing package cannot be found or installed,
the installation is terminated.
.It
A staging area is created under
.Pa /var/tmp ,
and the package is extracted into the staging area.
.It
If the package contains a
.Ar require
script (see
.Xr pkg_create 1 ) ,
it is executed with the following arguments:
.Bl -tag -width indentindent
.It Ar pkg-name
The name of the package being installed
.It Cm INSTALL
Keyword denoting to the script that it is to run an installation requirements
check
(the keyword is useful only to scripts which serve multiple functions).
.El
.Pp
If the
.Ar require
script exits with a non-zero status code, the installation is terminated.
.It
If the package contains an
.Ar install
script, it is executed with the following arguments:
.Bl -tag -width indentindent
.It Ar pkg-name
The name of the package being installed.
.It Cm PRE-INSTALL
Keyword denoting that the script is to perform any actions needed before
the package is installed.
.El
.Pp
If the
.Ar install
script exits with a non-zero status code, the installation is terminated.
.It
The packing list is 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
.Xr pkg_create 1 ) ,
then mtree is invoked as:
.Pp
.Bd -filled -offset indent -compact
.Cm mtree
.Fl u
.Fl f
.Ar mtreefile
.Fl d
.Fl e
.Fl p
.Pa prefix
.Ed
.Pp
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 executed with the following arguments:
.Bl -tag -width indentindent
.It Ar pkg_name
The name of the package being installed.
.It Cm POST-INSTALL
Keyword denoting that the script is to perform any actions needed
after the package has been installed.
.El
.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
.Ev 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
The
.Ar install
and
.Ar require
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 ENVIRONMENT
.Bl -tag -width PKG_TMPDIR
.It Ev PKG_PATH
If a given package name cannot be found,
the directories named by
.Ev PKG_PATH
are searched.
It should contain a series of entries separated by colons.
Each entry consists of a directory name.
The current directory may be indicated
implicitly by an empty directory name, or explicitly by a single
period
.Pq Ql \&. .
.It Ev PKG_DBDIR
Where to register packages instead of
.Pa /var/db/pkg .
.It Ev PKG_TMPDIR
Temporary area where packages will be extracted, instead of
.Pa /var/tmp .
.El
.Sh SEE ALSO
.Xr pkg_create 1 ,
.Xr pkg_delete 1 ,
.Xr pkg_info 1 ,
.Xr mkdtemp 3 ,
.Xr sysconf 3 ,
.Xr mtree 8
.Sh AUTHORS
.Bl -tag -width indent -compact
.It "Jordan Hubbard"
Initial work and ongoing development.
.It "John Kohl"
.Nx
refinements.
.El
.Sh CAVEATS
Package extraction does need a temporary area that
.Bl -bullet -compact
.It
is big enough to hold the complete extracted package,
.It
can hold executable scripts.
.El
.Pp
.Nm
looks through ${PKG_TMPDIR}, ${TMPDIR}, /var/tmp, /tmp, /usr/tmp
for such an area, in sequence.
.Pp
If ${TMPDIR} and /var/tmp are mounted noexec, you must set PKG_TMPDIR
to a suitable area, as
.Nm
has no way to check for noexec status except by failing to run installation
scripts.
.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
the link names are extracted with a single
.Xr tar 1
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.