Provided by: opam-docs_1.2.2-6_all 
NAME
opam - source-based OCaml package management
SYNOPSIS
opam COMMAND ...
DESCRIPTION
OPAM is a package manager for OCaml. It uses the powerful mancoosi tools to handle dependencies,
including support for version constraints, optional dependencies, and conflict management.
It has support for different remote repositories such as HTTP, rsync, git, darcs and mercurial. It
handles multiple OCaml versions concurrently, and is flexible enough to allow you to use your own
repositories and packages in addition to the central ones it provides.
Use either opam <command> --help or opam help <command> for more information on a specific command.
COMMAND ALIASES
info
An alias for show.
remote
An alias for repository.
uninstall
An alias for remove.
unpin
An alias for pin remove.
COMMANDS
config
Display configuration options for packages.
help
Display help about OPAM and OPAM commands.
init
Initialize OPAM state.
install
Install a list of packages.
lint
Checks and validate package description ('opam') files.
list
Display the list of available packages.
pin Pin a given package to a specific version or source.
reinstall
Reinstall a list of packages.
remove
Remove a list of packages.
repository
Manage OPAM repositories.
search
Search into the package list.
show
Display information about specific packages.
source
Get the source of an OPAM package.
switch
Manage multiple installation of compilers.
update
Update the list of available packages.
upgrade
Upgrade the installed package to latest version.
COMMON OPTIONS
These options are common to all commands.
--color=WHEN (absent=auto)
Colorize the output. WHEN must be one of `always', `never' or `auto'.
--criteria=CRITERIA
Specify user preferences for dependency solving for this run. Overrides both $OPAMCRITERIA and
$OPAMUPGRADECRITERIA. For details on the supported language, and the external solvers available, see
http://opam.ocaml.org/doc/Specifying_Solver_Preferences.html. A general guide to using solver
preferences can be found at http://www.dicosmo.org/Articles/usercriteria.pdf. The default value is
-count(down),-count(removed),-notuptodate(solution),-sum(solution,version-lag),-count(new) for
upgrades, and
-count(removed),-notuptodate(request),-sum(request,version-lag),-count(down),-notuptodate(changed),-count(changed),-notuptodate(solution),-sum(solution,version-lag)
otherwise.
--cudf=FILENAME
Debug option: Save the CUDF requests sent to the solver to FILENAME-<n>.cudf.
--debug
Print debug message to stderr. This is equivalent to setting $OPAMDEBUG to "true".
--debug-level=LEVEL
Like `--debug', but allows specifying the debug level (`--debug' sets it to 1). Equivalent to setting
$OPAMDEBUG to a positive integer.
--git-version
Print the git version if it exists and exit.
--help[=FMT] (default=pager)
Show this help in format FMT (pager, plain or groff).
--no-base-packages
Do not install base packages (useful for testing purposes). This is equivalent to setting
$OPAMNOBASEPACKAGES to a non-empty string.
--no-self-upgrade
OPAM will replace itself with a newer binary found at OPAMROOT/opam if present. This disables this
behaviour.
-q, --quiet
Be quiet when installing a new compiler.
--root=ROOT (absent=~/.opam)
Use ROOT as the current root path. This is equivalent to setting $OPAMROOT to ROOT.
--safe
Make sure nothing will be automatically updated or rewritten. Useful for calling from completion
scripts, for example. Will fail whenever such an operation is needed ; also avoids waiting for locks,
skips interactive questions and overrides the OPAMDEBUG variable.
--solver=CMD
Specify the name of the external dependency solver. The default value is aspcud. Either 'aspcud',
'packup' or a custom command that may contain the variables %{input}%, %{output}% and %{criteria}%
--strict
Fail whenever an error is found in a package definition or a configuration file. The default is to
continue silently if possible.
--switch=SWITCH
Use SWITCH as the current compiler switch. This is equivalent to setting $OPAMSWITCH to SWITCH.
--use-internal-solver, --no-aspcud
Force use of internal heuristics, even if an external solver is available.
-v, --verbose
Be more verbose, show package sub-commands and their output. Repeat to see more. Repeating n times is
equivalent to setting $OPAMVERBOSE to "n".
--version
Show version information.
-y, --yes
Disable interactive mode and answer yes to all questions that would otherwise be asked to the user.
This is equivalent to setting $OPAMYES to "true".
ENVIRONMENT VARIABLES
OPAM makes use of the environment variables listed here. Boolean variables should be set to "0", "no" of
"false" to disable, "1", "yes" or "true" to enable.
OPAMCOLOR, when set to always or never, sets a default value for the --color option.
OPAMCRITERIA specifies user preferences for dependency solving.The default value is
-count(removed),-notuptodate(request),-sum(request,version-lag),-count(down),-notuptodate(changed),-count(changed),-notuptodate(solution),-sum(solution,version-lag).
See also option --criteria
OPAMCURL can be used to select a given 'curl' program. See OPAMFETCH for more options.
OPAMDEBUG see options `--debug' and `--debug-level'.
OPAMDOWNLOADJOBS sets the maximum number of simultaneous downloads.
OPAMEXTERNALSOLVER see option `--solver'.
OPAMFETCH specifies how to download files: either `wget', `curl' or a custom command where variables
%{url}%, %{out}%, %{retries}%, %{compress}% and %{checksum}% will be replaced. Overrides the
'download-command' value from the main config file.
OPAMJOBS sets the maximum number of parallel workers to run.
OPAMLOCKRETRIES sets the number of tries after which OPAM gives up acquiring its lock and fails. <= 0
means infinite wait.
OPAMNO answer no to any question asked.
OPAMNOASPCUD see option `--no-aspcud'.
OPAMNOSELFUPGRADE see option `--no-self-upgrade'.
OPAMPINKINDAUTO if set, version control systems are detected when pinning to a local path.
OPAMREQUIRECHECKSUMS see option `--require-checksums'.
OPAMRETRY sets the number of tries before failing downloads.
OPAMROOT see option `--root'. This is automatically set by `opam config env --root=DIR' when DIR is
non-default or OPAMROOT is already defined.
OPAMSAFE see option `--safe'
OPAMSKIPVERSIONCHECKS bypasses some version checks. Unsafe, for compatibility testing only.
OPAMSOLVERTIMEOUT change the time allowance of the internal solver.
OPAMSTATUSLINE display a dynamic status line showing what's currently going on on the terminal. (one of
one of `always', `never' or `auto')
OPAMSWITCH see option `--switch'. Automatically set by `opam config env --switch=SWITCH'.
OPAMUPGRADECRITERIA specifies user preferences for dependency solving when performing an upgrade.
Overrides OPAMCRITERIA in upgrades if both are set.The default value is
-count(down),-count(removed),-notuptodate(solution),-sum(solution,version-lag),-count(new). See also
option --criteria
OPAMUSEINTERNALSOLVER see option `--use-internal-solver'.
OPAMUTF8 use UTF8 characters in output (one of one of `always', `never' or `auto'). By default `auto',
which is determined from the locale).
OPAMUTF8MSGS use extended UTF8 characters (camels) in OPAM messages. Implies OPAMUTF8. This is set by
default on OSX only.
OPAMVAR_var overrides the contents of the variable var when substituting `%{var}%` strings in `opam`
files.
OPAMVAR_package_var overrides the contents of the variable package:var when substituting
`%{package:var}%` strings in `opam` files.
OPAMVERBOSE see option `--verbose'.
OPAMYES see option `--yes'.
FURTHER DOCUMENTATION
See https://opam.ocaml.org.
AUTHORS
Thomas Gazagnaire <thomas@gazagnaire.org> Anil Madhavapeddy <anil@recoil.org> Fabrice Le Fessant <Fabrice.Le_fessant@inria.fr> Frederic Tuong <tuong@users.gforge.inria.fr> Louis Gesbert <louis.gesbert@ocamlpro.com> Vincent Bernardoff <vb@luminar.eu.org> Guillem Rieu <guillem.rieu@ocamlpro.com> Roberto Di Cosmo <roberto@dicosmo.org>
BUGS
Check bug reports at https://github.com/ocaml/opam/issues.