usepackage(1)
NAME
usepackage - Usepackage Environment Manager
SYNOPSIS
See use(1).
DESCRIPTION
Usepackage is an environment management program. It is based on the principle of packages - collections of executables that share a common set of necessary environment variables, such as PATH, MANPATH or LD_LIBRARY_PATH. For each given package, use sources the appropriate environment information into the current shell. The environment information is specified in packages files, see PACKAGES. The usepackage executable is the backend program used to generate environment information suitable for sourcing into a running shell. The use frontend should be invoked to actually effect changes to the environment, see use(1). OPTIONS -v Output verbose information to the standard error stream. -s Silence warnings for un-matched packages. This is useful in a shell rc script when a package is known not to be available on all architectures that the shell is used on, see PACKAGES. -c Force csh style environment output. -b Force bourne shell style environment output. -f file Specify an alternate initial configuration file, see PACKAGES. -l List available packages and groups, see ANNOTATIONS and GROUPS.
PACKAGES
Usepackage reads package environment information from the configuration
file as follows:
LOAD ORDER
When Usepackage starts up, it loads an initial configuration file, the
name of this file may be given on the command line (see OPTIONS),
otherwise it defaults to the builtin name "usepackage.conf" (see
FILES). This file is located by searching along a path which defaults
to:
/etc:~:.
This path may be overridden with the PACKAGES_PATH environment variable
(see ENVIRONMENT). A packages file may contain inclusion directives
which cause the sourcing of other files at given points. An inclusion
directive looks like:
(include file-name)
The same location mechanism is used to find "file-name" as for the
initial configuration file. A package file name may also be given as an
absolute file name or may be shell-style user directory, tilde (~),
relative.
SYNTAX
A package file consists of comments, delimited by a leading hash (#),
or package definitions of the form:
package [arch [os [version [host [shell]]]]]
[<= requires ...] : setting [, setting ...] ;
The package, arch, os, version, host, and shell parts may be simple
shell-style patterns of the form:
* matches anything.
foo* matches "foo", "foobar" etc.
{foo,bar} matches "foo" or "bar".
The requires list specifies the names of other packages which must be
sourced into the environment before the settings for this package are
processed.
A setting is either a variable definition, an alias definition (both
described below) or a section of text to be directly evaluated in the
shell, delimited with <[ and ]>, for example:
<[ /usr/local/bin/test-init ]>
When Usepackage searches for the definition for a particular package,
it compares each line in the packages file against the name of the
package given (package) and system-dependant information for the
execution host, as obtained by uname(2). This information is the
hardware implementation (platform), the operating system name (os), the
operating system version (version) and the hostname (host). Comparisons
are case-insensitive. If a match is obtained then the given variable
definitions and script sections are processed to modify the
environment. A variable definition may have one of the following
forms:
var-name = "string"
var-name = path-list
var-name += path-list
var-name += "string"
var-name =+ path-list
var-name =+ "string"
The first sets the given variable to a literal string value, the second
sets the given variable to a path list, the third prepends the current
value of a variable with the given path list, and the fourth interprets
the literal string as a path list and prepends it to the current value
of the variable. The fourth and fifth forms do the same, but append to
the current value of the variable. Path lists are colon (:) separated
lists of directories and may contain shell-style tilde (~), user-
relative, directories which will be expanded automatically (except when
the path list is given as a literal string). When pre-pending paths to
a variable, duplicate paths are removed from the original value first.
In addition, Usepackage can optionally test for the existence of paths
before setting or adding them to variables. This is done with the test
form of the above operators:
var-name ?= path-list
var-name ?+= path-list
var-name ?+= "string"
These operate as per the definitions above, but will ignore path
components that don't exist.
An alias definition has one of the following forms:
alias name = name
alias name = path
alias name = "string"
These will define a matching shell alias.
GROUPS
In addition to the package definitions in a packages file, there may
also be group definitions. These have the following syntax:
group := package [, package ...] ;
Usepackage searches for a given package name in the defined groups
first, if the given name matchs a group name then the packages defined
as part of that group are sourced into the environment together. A
group definition may not reference other groups and may not contain
patterns.
ANNOTATIONS
In order to give useful package information to the user, annotations
may be placed in the packages file that give summaries of packages.
These annotations have the form:
>> name : "description" <<
Usepackage collects these annotations together and displays them when
called with the -l flag, see OPTIONS. These annotations have no impact
on the package mechanism and need not necessarily be beside or
correspond to the package definitions (although this is the sensible
way to arrange things).
EXAMPLE
The following fragment of a packages file illustrates the main
features:
# GNU software is available everywhere:
>> GNU : "The GNU project software" <<
GNU : PATH += /usr/local/gnu/bin,
MANPATH += /usr/local/gnu/man ;
# CVS requires RCS which is found in the GNU package, but
# is only available on SPARC Solaris machines:
>> CVS : "Concurrent Versions System revision control" <<
CVS sun4* SunOS 5.* <= GNU :
CVSROOT = /usr/src/cvsroot,
CVSEDITOR = "vi",
PATH += /usr/local/cvs/bin,
MANPATH += /usr/local/cvs/man ;
# User bin directories (Solaris will run SunOS 4 binaries):
# (Only added to the path if the directories actually exist)
>> user : "User's own programs" <<
user sun4* SunOS : PATH ?+= ~/bin/sun4 ;
user sun4* SunOS 5.* : PATH ?+= ~/bin/solaris ;
user alpha OSF : PATH ?+= ~/bin/alpha ;
# Useful aliases:
aliases : alias more = less,
alias ls = "ls --color",
alias cc = /usr/bin/gcc ;
# Special function for zsh:
>> zsh-function : "Special zsh function" <<
zsh-function * * * * zsh :
<[ hello() { echo "Hello World!"; } ]> ;
# include standard packages:
(include packages.standard)
# security hole:
dot : PATH += . ;
# groups:
user-setup := standard, user ;
programmer-setup := standard, CVS, user, dot ;
Note the use of Operating System version numbers to distinguish between
SunOS 4 and Solaris (SunOS 5), the use of "sun4*" to match the multiple
different platform versions of SPARC machines (sun4m, sun4c, etc.) and
the fact that package "user" on a SPARC Solaris machine will match both
of the first two lines of the "user" package section, resulting in the
"solaris" directory and the "sun4" directory being added into the PATH.
Assuming the appropriate shell setup script has been sourced - see
use(1) - then the following command will cause the CVS environment
(including the GNU environment) to be sourced:
$ use CVS
Note that on a DEC Alpha machine, this will generate a warning like:
$ use CVS
warning: no match for package `CVS' on this host.
In a shell script which is executed on a number of different platforms
(such as the shell startup script). These warnings may be silenced (see
OPTIONS).
FILES
/usr/share/usepackage/usepackage.conf
The default master packages file.
/usr/share/usepackage/use.csh
Shell setup for csh and derivatives.
/usr/share/usepackage/use.bsh
Shell setup for bourne shell and derivatives.
/usr/share/usepackage/use.ksh
Shell setup for ksh.
/usr/bin/usepackage
The underlying Usepackage executable.
ENVIRONMENT
Other than the reading and re-definition of environment variables for
package setup, use also uses the following environment variables for
user configuration:
PACKAGES_PATH Colon-separated path list giving the directories to
search for configuration files. Shell-style tilde (~)
user-directory escapes are expanded.
HOME If present in the environment, this is used to provide
the expansion for the tilde (~) user-directory.
SHELL If present in the environment, the last path component
of this is used for shell matching (see SYNTAX) and
detecting the style of environment output that should be
used (see OPTIONS).
COPYRIGHT
Usepackage Environment Manager Copyright (C) 1995-2015 Jonathan Hogg <[email protected]> This program is free software; you can redistribute it and/or modify it under the terms of the GNU General Public License as published by the Free Software Foundation; either version 2 of the License, or (at your option) any later version. This program is distributed in the hope that it will be useful, but WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for more details. You should have received a copy of the GNU General Public License along with this program; if not, write to the Free Software Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
SEE ALSO
use(1), csh(1), sh(1), ksh(1), env(1), environ(5), getenv(3C), uname(1), uname(2)
Opportunity
Personal Opportunity - Free software gives you access to billions of dollars of software at no cost. Use this software for your business, personal use or to develop a profitable skill. Access to source code provides access to a level of capabilities/information that companies protect though copyrights. Open source is a core component of the Internet and it is available to you. Leverage the billions of dollars in resources and capabilities to build a career, establish a business or change the world. The potential is endless for those who understand the opportunity.
Business Opportunity - Goldman Sachs, IBM and countless large corporations are leveraging open source to reduce costs, develop products and increase their bottom lines. Learn what these companies know about open source and how open source can give you the advantage.
Free Software
Free Software provides computer programs and capabilities at no cost but more importantly, it provides the freedom to run, edit, contribute to, and share the software. The importance of free software is a matter of access, not price. Software at no cost is a benefit but ownership rights to the software and source code is far more significant.
Free Office Software - The Libre Office suite provides top desktop productivity tools for free. This includes, a word processor, spreadsheet, presentation engine, drawing and flowcharting, database and math applications. Libre Office is available for Linux or Windows.
Free Books
The Free Books Library is a collection of thousands of the most popular public domain books in an online readable format. The collection includes great classical literature and more recent works where the U.S. copyright has expired. These books are yours to read and use without restrictions.
Source Code - Want to change a program or know how it works? Open Source provides the source code for its programs so that anyone can use, modify or learn how to write those programs themselves. Visit the GNU source code repositories to download the source.
Education
Study at Harvard, Stanford or MIT - Open edX provides free online courses from Harvard, MIT, Columbia, UC Berkeley and other top Universities. Hundreds of courses for almost all major subjects and course levels. Open edx also offers some paid courses and selected certifications.
Linux Manual Pages - A man or manual page is a form of software documentation found on Linux/Unix operating systems. Topics covered include computer programs (including library and system calls), formal standards and conventions, and even abstract concepts.
