Provided by: 0install-core_2.10-2_amd64 
NAME
0install — a decentralised software installation system
SYNOPSIS
Downloading and running:
0install select URI
0install download URI
0install run URI [ARG]...
0install update URI
Applications:
0install add NAME URI
0install show NAME
0install update NAME
0install whatchanged NAME
0install destroy NAME
Other commands:
0install config [NAME [VALUE]]
0install import FEED
0install list PATTERN
0install search QUERY
0install add-feed [INTERFACE] FEED
0install remove-feed [INTERFACE] FEED
0install list-feeds URI
0install man COMMAND
0install digest DIRECTORY | ARCHIVE [EXTRACT]
0install store ...
0install slave
DESCRIPTION
Zero Install is a decentralised cross-distribution software installation system. Programs and libraries
are identified by URIs, and there is no need for a central repository. Zero Install ensures that packages
cannot conflict with each other and that programs can be shared between mutually untrusting users. See
the web-site for more information:
http://0install.net/
The simplest case is to ask 0install to run a program, given its URI. For example:
0install run http://rox.sourceforge.net/2005/interfaces/Edit
The first time you do this, details about available versions of the program are downloaded and cached,
along with details about any libraries it depends on.
Zero Install will run a solver to select the best version of each component to use. For example, it will
select binaries that are compatible with your CPU and operating system, in your preferred language, and
marked "stable" (by default).
If $DISPLAY is set, 0install will display a window where you can confirm (or change) the selected
versions.
It will then download the corresponding archives for those versions and store them in the cache too. Each
package unpacks to its own directory.
Finally, 0install will launch the program, setting environment variables to let it locate its libraries.
GLOBAL OPTIONS
The first non-option argument to 0install is the particular sub-command you want to perform; these are
described in detail in the next section.
However, there are some options that apply to all operations. These are:
-c, --console
Never use the GUI. Normally, 0install switches to graphical mode if it needs to download anything
from the network (unless DISPLAY is not set).
--dry-run
Do not save any changes to disk, and do not actually run the program. Instead, just print out the
changes that would have been made. Note that, as 0install is a very safe system, there is
generally no need to use this option. However, it can be useful as a learning aid or for testing.
-h, --help
Show the built-in help text.
-o, --offline
Run in off-line mode, overriding the default setting. This prevents 0install from checking for
updates, and from downloading updates even if it knows about them.
-v, --verbose
More verbose output. Use twice for even more verbose output.
--with-store=DIR
Append a directory to the list of implementation caches. Each sub-directory of DIR contains the
contents of one version of a program or library.
SUB-COMMANDS
0install select [OPTIONS] URI
Select a version of the program identified by URI, and compatible versions of all of its dependencies.
The information about available versions is downloaded if it's not yet in the cache.
The URI can be an HTTP URL, such as `http://site/program.xml' or a local path name like
`file:///path/to/program.xml'.
For HTTP URLs, the remote file is a signed XML document. If the key is not known and trusted, you will be
prompted to accept it first. Local feed files are not signed (any signature will be ignored).
You can also specify a local selections document, as created previously using the --xml option, rather
than a feed. In that case, 0install simply uses those versions without running the solver.
After selecting (but not downloading) a set of versions, the selection is displayed in a human-readable
format. Use --xml to get machine-readable output.
If a set of versions cannot be selected using the cached information, 0install will check for updates
first.
If a set of versions can be selected based on the currently-cached information, but that information is
getting stale, 0install will immediately return the current selection and will also start a background
process to check for updates. The `freshness' configuration setting controls when cached information is
considered to be stale.
Options for select:
--before=VERSION
Select a version earlier than VERSION (i.e. force the use of an old version of the program). You
can only restrict the version of the program itself using this option, not the version of any
dependencies.
--command=COMMAND
Some programs provide multiple commands. This selects which one you want. Common values are `run'
(the default), `test' (used by 0test) and `compile' (used by 0compile). You can also use
--command="" if you don't want to run any command (for example, if the package contains data
rather than a program).
--may-compile
Treat every source implementation as a potential binary. This can be used to find what needs to
be compiled to run a program. Currently this is only available for "0install select".
--message=MESSAGE
If we show a dialog box for the download, display MESSAGE to the user to explain why the download
is needed.
--not-before=VERSION
The selected version must not be earlier than VERSION. e.g. if you want to run version 2.0 or
later, use --not-before=2.0.
--refresh
Download a fresh copy of all used feeds before selecting. Normally, cached copies will be used if
available (checking for updates later, in the background).
--source
Select source code rather than a binary. This is used internally by `0compile'.
--version=RANGE
Require a version of the main program within the given range. This can be a simple number (e.g.
--version=2.3) or a range (e.g. --version=2.3..!2.7). For ranges, either end may be omitted. The
"!" indicates that the range excludes the final value. Alternatives can be separated by "|", e.g.
"2.6..!3 | 3.2.." (allows 2.6, 2.7, 3.2, etc, but not 2.5 or 3.0).
--version-for=URI RANGE
Specifies the range (as for --version) for any library or sub-component. If URI is the URI of the
main program then this is equivalent to using --version.
--xml Print the set of chosen implementations as an XML document to stdout. This can be used later with
the `download' and `run' sub-commands.
`select' returns an exit status of zero if it selected a set of versions, and a status of 1 if it could
not find a consistent set.
0install download [OPTIONS] URI
This behaves similarly to `0install select', except that it also downloads the selected versions if they
are not already cached. Unlike `select', it does not print the selected versions by default.
All options for `select' can also be used for `download'. In addition, these options are available:
--show Print the selected versions in a human-readable format to stdout.
`download' returns an exit status of zero if it selected a suitable set of versions and they are now all
downloaded and in the cache. It returns a status of 1 otherwise.
0install run [OPTIONS] URI [ARGS]
This behaves similarly to `0install download', except that it also runs the program after ensuring it is
in the cache.
To avoid having to keep typing the full URI, use the `0install add' command to create shortcuts to run
your programs.
All options for `select' can also be used for `run' except for --xml. In addition, these options are
available:
-m, --main=MAIN
Run the specified executable instead of the default. If MAIN starts with '/' then the path is
relative to the implementation's top-level directory, whereas otherwise it is relative to the
directory containing the default MAIN program. For example, if the default MAIN is bin/svn then
using --main=svnadmin will run .../bin/svnadmin instead. This option has been largely superseded
by the newer --command option.
-w, --wrapper=WRAPPER
Instead of executing the chosen program directly, run WRAPPER PROGRAM ARGS. This is useful for
running debuggers and tracing tools on the program (rather than on 0install!). Note that the
wrapper is executed in the environment selected by the program; hence, this mechanism cannot be
used for sandboxing. See the DEBUGGING section below.
Note that any options after `URI' will be passed to the program being run rather than being interpreted
by 0install.
`run' returns an exit status of 1 if the download step failed. Otherwise, the exit status will be the
exit status of the program being run.
0install update [OPTIONS] URI
Check for updates to the program and download them if found. This is similar to 0install download
--refresh, except that it prints information about whether any changes were found.
The options are the same as for `select'.
0install import FEED
Import a feed from a local file, as if it had been downloaded from the network. This is useful when
testing a feed file, to avoid uploading it to a remote server in order to download it again. The file
must have a trusted digital signature, as when fetching from the network.
It is also useful when installing a feed from a CD or similar. Note: to create a full bundle, for
archiving or distribution on CD, see 0export(1).
0install add-feed [INTERFACE] FEED
Register an additional source of implementations (versions) of a program.
For example, when you check out a developer version of a project, it may contain an XML feed file. To add
this version to the list of available versions, use `add-feed' on the XML file. The file is not copied,
so you don't need to re-add the feed each time it is updated. You will probably also want to set the
`help_with_testing' configuration option to ensure that testing versions are selected by default.
Note that if you just want to run the program, you can invoke 0install on the feed file directly (without
using `add-feed'). This will force the it to use that version, but won't affect what happens when you run
it using the URI as normal. Use `add-feed' when you want to use the developer version even when using the
URI, or if the program is a library (and thus referenced by URI by other programs).
0install remove-feed [INTERFACE] FEED
Un-register a feed, reversing the effect of `add-feed'. If INTERFACE is not given, you will be prompted
to choose which INTERFACE to remove it from.
0install list-feeds URI
List all extra feeds added to URI using `add-feed'.
0install list [PATTERN]
List all locally-cached interface (program) URIs. If a search term is given, only URIs containing that
string are shown (case insensitive).
0install search QUERY
Send the query string to the mirror server and display any interfaces it returns. Note that the default
mirror server indexes all known feeds, regardless of quality; you must decide whether to trust the
programs before running them.
0install config [NAME [VALUE]]
View or change configuration settings.
With no arguments, `0install config' displays all configuration settings. With one argument, it displays
the current value of the named setting. With two arguments, it sets the setting to the given value.
0install man COMMAND
Show the man-page of the given command. If the single argument COMMAND is a launcher script (created by
"0install add") then the man-page is searched for by 0install, otherwise the arguments are passed through
directly to the system's man command. This allows you to do:
alias man="0install man --"
0install digest DIRECTORY | ARCHIVE [EXTRACT]
Calculate the secure hash of an implementation. This is a unique "fingerprint" of a directory and all the
files and subdirectories it contains. When publishing a program using 0install, this value must be placed
in the XML file.
-m, --algorithm=HASH
Select the secure hash function to be used. Supported values are "sha1new" (the default), "sha256"
and "sha256new".
If an archive is given then the hash is for the directory that would be created if the archive were
unpacked (or the EXTRACT subdirectory of it, if one is specified).
-m, --manifest
-d, --digest
These options control whether to display the manifest itself (one line for each file or directory) or the
manifest's digest (or both). If neither option is given, the digest is displayed.
0install --version
This can be used (without any command) the get version of 0install itself.
APPLICATIONS
An application provides an easy way to run a program without typing the full URL each time.
0install add NAME URI
Creates a new application called NAME (which can be whatever you want) to run the program URI. A
directory (by default, ~/.config/0install.net/apps/NAME) is created to record the current selections, as
would be produced by "0install select --xml URI".
A launcher command (also called NAME) will be created in $PATH to provide an easy way to run the
application. For example, to add and run ROX-Filer:
$ 0install add rox http://rox.sourceforge.net/2005/interfaces/ROX-Filer
$ rox
If additional requirements are given (as for "0install select", e.g. --before), they are stored with the
application and apply to all updates.
0install show NAME | SELECTIONS
Show the current selections for this application (or the contents of the given selections file). By
default, the output is in the same format as for "0install select", and the --xml option has the same
effect.
-r, --root-uri
Just display the root interface URI (e.g. the URI passed to "0install add" when this application
was created).
0install update NAME
The feeds used to make the selections are updated and a new set of selections is generated and saved into
the application's directory. Even if you don't run this command explicitly, 0install will check for
updates if you run the program and it hasn't been updated for a while. This happens in the background and
does not delay starting the program.
If additional requirements are given (as for "0install select", e.g. --before), they update the
requirements stored with the application and apply to this and future updates.
0install whatchanged NAME
Show the differences between the current and previous selections for this application. Various times may
also be displayed: "Last checked" is the last time we successfully checked for updates (even if none was
found), "Last attempted update" is the last time we tried to check for updates, and "Last update" is the
last time changes were found. If "Last attempted update" is shown, then either the last updated failed or
an update is currently in progress.
By default, only changes that resulted in a different version being selected are shown. To see all
changes, use --full. Note that at most one set of selections is saved per day.
0install destroy NAME
The application NAME is deleted, along with any launchers added for it.
0install store ...
Provides low-level access to the store of cached implementations. See the 0store(1) man-page for details.
0install slave
Run 0install in slave mode (currently EXPERIMENTAL and likely to change). You can send JSON requests to
the process's standard input and receive responses from its standard output.
DEBUGGING TIPS
To debug 0install itself, use the --verbose and --console options. For example:
$ 0install -vvc run http://myprog
To trace or debug programs run by 0install, use the --wrapper option. For example, to run myprog --help,
displaying all calls to open(2):
$ 0install run --wrapper="strace -e open" http://myprog --help
To run the application under the gdb debugger:
$ 0install run --wrapper="gdb --args" http://myprog --help
FILES
Configuration files (see freedesktop.org basedir spec):
~/.config/0install.net/injector/global
Global configuration settings.
~/.config/0install.net/injector/trustdb.xml
List of trusted keys.
~/.config/0install.net/injector/feeds
Per-feed information (e.g. time of last check).
~/.config/0install.net/injector/interfaces
Per-interface settings (preferred stability and any extra feeds that have been registered).
Cached data (can be re-downloaded if lost):
~/.cache/0install.net/interfaces
Downloaded cached feed files.
~/.cache/0install.net/implementations
Downloaded cached implementations, indexed by manifest digest.
See the 0store(1) man page for more information.
ENVIRONMENT VARIABLES
XDG_* The configuration and cache directories can be changed using XDG_CONFIG_HOME, XDG_CONFIG_DIRS,
XDG_CACHE_HOME and XDG_CACHE_DIRS, as usual.
ZEROINSTALL_PORTABLE_BASE
If this is set, then the XDG_ variables are ignored and the configuration and cache are stored in
$ZEROINSTALL_PORTABLE_BASE/config and $ZEROINSTALL_PORTABLE_BASE/cache instead.
ZEROINSTALL_EXTERNAL_STORE
When 0install wants to add an archive to the cache, it calls this program instead of doing it
itself. This is used internally on Windows to connect to some .NET code. It may change in future.
LICENSE
Copyright (C) 2013 Thomas Leonard.
You may redistribute copies of this program under the terms of the GNU Lesser General Public License.
BUGS
Please report bugs to the developer mailing list:
http://0install.net/support.html
AUTHOR
Zero Install was created by Thomas Leonard, with help from many others. See the Git log for details.
SEE ALSO
0store(1), 0launch(1) The Zero Install web-site: http://0install.net