Provided by: opam-doc_2.3.0-1_all 
NAME
opam-init - Initialize opam state, or set init options.
SYNOPSIS
opam init [OPTION]… [NAME] [ADDRESS]
DESCRIPTION
Initialise the opam state, or update opam init options
The init command initialises a local "opam root" (by default, ~/.opam/) that holds opam's data and
packages. This is a necessary step for normal operation of opam. The initial software repositories are
fetched, and an initial 'switch' can also be installed, according to the configuration and options. These
can be afterwards configured using opam switch and opam repository.
The initial repository and defaults can be set through a configuration file found at ~/.opamrc or
/etc/opamrc.
Additionally, this command allows one to customise some aspects of opam's shell integration, when run
initially (avoiding the interactive dialog), but also at any later time.
ARGUMENTS
ADDRESS
Address of the initial package repository, when creating a new opam root.
NAME (absent=default)
Name of the initial repository, when creating a new opam root.
OPTIONS
-a, --auto-setup
Automatically do a full setup, including adding a line to your shell init files.
--bare
Initialise the opam state, but don't setup any compiler switch yet.
--bypass-checks
Skip checks on required or recommended tools, and assume everything is fine
-c PACKAGE, --compiler=PACKAGE
Set the compiler to install (when creating an initial switch)
--config=FILE
Use the given init config file. If repeated, latest has the highest priority (i.e. each field gets
its value from where it was defined last). Specifying a URL pointing to a config file instead is
allowed.
--cygwin-extra-packages=CYGWIN_PACKAGES
Windows only (Experimental). Specify additional packages to install with --cygwin-internal-install
--cygwin-internal-install
Windows only (Experimental). Let opam setup and manage an internal Cygwin install (recommended)
--cygwin-local-install
Windows only (Experimental). Use preexistent Cygwin install
--cygwin-location=DIR
Windows only (Experimental). Specify Cygwin root location
--disable-completion
Disable shell completion in opam init scripts.
--disable-sandboxing
Use a default configuration with sandboxing disabled (note that this may be overridden by `opamrc' if
--no-opamrc is not specified or --config is used). Use this at your own risk, without sandboxing it
is possible for a broken package script to delete all your files.
--disable-shell-hook
Disable registration of a shell hook in opam init scripts.
--dot-profile=FILENAME
Name of the configuration file to update instead of ~/.profile or ~/.zshrc based on shell detection.
--enable-completion
Setup shell completion in opam init scripts, for supported shells.
--enable-shell-hook
Setup opam init scripts to register a shell hook that will automatically keep the shell environment
up-to-date at every prompt.
--git-location=DIR
Windows only (Experimental). Specify git binary directory. Ensure that it doesn't contains bash in
the same directory
-i, --interactive
Run the setup interactively (this is the default for an initial run, or when no more specific options
are specified)
-k KIND, --kind=KIND
Specify the kind of the repository to be used (one of http, local, git, darcs or hg).
-n, --no-setup
Do not update the user shell configuration to setup opam. Also implies --disable-shell-hook, unless
--interactive or specified otherwise
--no-cygwin-setup
Experimental. Don't setup Cygwin
--no-git-location
Experimental. Don't specify nor ask to specify git binary directory.
--no-opamrc
Don't read `/etc/opamrc' or `~/.opamrc': use the default settings and the files specified through
--config only
--reinit
Re-run the initial checks and setup, according to opamrc, even if this is not a new opam root
--shell=SHELL
Sets the configuration mode for opam environment appropriate for SHELL. One of one of bash, sh, csh,
zsh, fish, pwsh, cmd or powershell. Guessed from the parent processes and the $SHELL variable by
default.
--shell-setup
Automatically setup the user shell configuration for opam, e.g. adding a line to the `~/.profile'
file.
--show-default-opamrc
Print the built-in default configuration to stdout and exit
CONFIGURATION FILE
Any field from the built-in initial configuration can be overridden through ~/.opamrc, /etc/opamrc, or a
file supplied with --config. The default configuration for this version of opam can be obtained using
--show-default-opamrc.
PACKAGE BUILD OPTIONS
--assume-depexts
Skip the installation step for any missing system packages, and attempt to proceed with compilation
of the opam packages anyway. If the installation is successful, opam won't prompt again about these
system packages. Only meaningful if external dependency handling is enabled.
-b, --keep-build-dir
Keep the build directories after compiling packages. This is equivalent to setting $OPAMKEEPBUILDDIR
to "true".
--build-doc
Removed in 2.1, use --with-doc instead.
--build-test
Removed in 2.1, use --with-test instead.
-d, --with-doc
Build the package documentation. This only affects packages listed on the command-line. This is
equivalent to setting $OPAMWITHDOC (or the deprecated $OPAMBUILDDOC) to "true".
--dry-run
Simulate the command, but don't actually perform any changes. This also can be set with environment
variable $OPAMDEBUG.
--fake
This option registers the actions into the opam database, without actually performing them. WARNING:
This option is dangerous and likely to break your opam environment. You probably want --dry-run.
You've been warned.
--ignore-constraints-on[=PACKAGES] (default=)
Forces opam to ignore version constraints on all dependencies to the listed packages. This can be
used to test compatibility, but expect builds to break when using this. Note that availability of the
packages as well as version constraints on optional dependencies and conflicts are unaffected. This
is equivalent to setting $OPAMIGNORECONSTRAINTS.
--inplace-build
When compiling a package which has its source bound to a local directory, process the build and
install actions directly in that directory, rather than in a clean copy handled by opam. This only
affects packages that are explicitly listed on the command-line. This is equivalent to setting
$OPAMINPLACEBUILD to "true".
-j JOBS, --jobs=JOBS
Set the maximal number of concurrent jobs to use. The default value is calculated from the number of
cores. You can also set it using the $OPAMJOBS environment variable.
--lock-suffix=SUFFIX (absent=locked)
Set locked files suffix to SUFFIX.
--locked
In commands that use opam files found from pinned sources, if a variant of the file with an added
.locked extension is found (e.g. foo.opam.locked besides foo.opam), that will be used instead. This
is typically useful to offer a more specific set of dependencies and reproduce similar build
contexts, hence the name. The lockoption can be used to generate such files, based on the versions
of the dependencies currently installed on the host. This is equivalent to setting the $OPAMLOCKED
environment variable. Note that this option doesn't generally affect already pinned packages.
-m MAKE, --make=MAKE
Removed in 2.1, use opam config set[-global] make MAKE instead.
--no-checksums
Do not verify the checksum of downloaded archives.This is equivalent to setting $OPAMNOCHECKSUMS to
"true".
--no-depexts
Temporarily disables handling of external dependencies. This can be used if a package is not
available on your system package manager, but you installed the required dependency by hand. Implies
--assume-depexts, and stores the exceptions upon success as well.
--require-checksums
Reject the installation of packages that don't provide a checksum for the upstream archives. This is
equivalent to setting $OPAMREQUIRECHECKSUMS to "true".
--reuse-build-dir
Reuse existing build directories (kept by using --keep-build-dir), instead of compiling from a fresh
clone of the source. This can be faster, but also lead to failures if the build systems of the
packages don't handle upgrades of dependencies well. This is equivalent to setting $OPAMREUSEBUILDDIR
to "true".
--show-actions
Call the solver and display the actions. Don't perform any changes. This is equivalent to setting
$OPAMSHOW.
--skip-updates
When running an install, upgrade or reinstall on source-pinned packages, they are normally updated
from their origin first. This flag disables that behaviour and will keep them to their version in
cache. This is equivalent to setting $OPAMSKIPUPDATE.
-t, --with-test
Build and run the package unit-tests. This only affects packages listed on the command-line. This is
equivalent to setting $OPAMWITHTEST (or the deprecated $OPAMBUILDTEST) to "true".
--unlock-base
Removed in 2.1, use --update-invariant instead.
--update-invariant
Allow changes to the packages set as switch base (typically, the main compiler). Use with caution.
This is equivalent to setting the $OPAMUNLOCKBASE environment variable
--verbose-on=PACKAGES
Be more verbose on specific packages.This is equivalent to setting $OPAMVERBOSE.
--with-dev-setup
Include development tools only dependencies.
COMMON OPTIONS
These options are common to all commands.
--best-effort
Don't fail if all requested packages can't be installed: try to install as many as possible. Note
that not all external solvers may support this option (recent versions of aspcud or mccs should).
This is equivalent to setting $OPAMBESTEFFORT environment variable.
--cli=MAJOR.MINOR (absent=2.3)
Use the command-line interface syntax and semantics of MAJOR.MINOR. Intended for any persistent use
of opam (scripts, blog posts, etc.), any version of opam in the same MAJOR series will behave as for
the specified MINOR release. The flag was not available in opam 2.0, so to select the 2.0 CLI, set
the OPAMCLI environment variable to 2.0 instead of using this parameter.
--color=WHEN
Colorize the output. WHEN must be one of always, never or auto.
--confirm-level=LEVEL
Confirmation level, LEVEL must be one of ask, no, yes or unsafe-yes. Can be specified more than once.
If --yes or --no are also given, the value of the last --confirm-level is taken into account. This is
equivalent to setting $OPAMCONFIRMLEVEL`.
--criteria=CRITERIA
Specify user preferences for dependency solving for this run. Overrides $OPAMCRITERIA,
$OPAMFIXUPCRITERIA and $OPAMUPGRADECRITERIA. For details on the supported language, and the external
solvers available, see http://opam.ocaml.org/doc/External_solvers.html. A general guide to using
solver preferences can be found at http://www.dicosmo.org/Articles/usercriteria.pdf.
--cudf=FILENAME
Debug option: Save the CUDF requests sent to the solver to FILENAME-<n>.cudf where <n> is the n-th
call to the solver during the opam run.
--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 of opam, if set (i.e. you are using a development version), and exit.
--help[=FMT] (default=auto)
Show this help in format FMT. The value FMT must be one of auto, pager, groff or plain. With auto,
the format is pager or plain whenever the TERM env var is dumb or undefined.
--ignore-pin-depends
Ignore extra pins required by packages that get pinned, either manually through opam pin or through
opam install DIR. This is equivalent to setting IGNOREPINDEPENDS=true.
--json=FILENAME
Save the results of the opam run in a computer-readable file. If the filename contains the character
`%', it will be replaced by an index that doesn't overwrite an existing file. Similar to setting the
$OPAMJSON variable.
--no
Answer no to all opam yes/no questions without prompting. See also --confirm-level. This is
equivalent to setting $OPAMNO to "true".
--no-aspcud
Removed in 2.1.
--no-auto-upgrade
When configuring or updating a repository that is written for an earlier opam version (1.2), opam
internally converts it to the current format. This disables this behaviour. Note that repositories
should define their format version in a 'repo' file at their root, or they will be assumed to be in
the older format. It is, in any case, preferable to upgrade the repositories manually using opam
admin upgrade [--mirror URL] when possible.
--no-self-upgrade
Opam will replace itself with a newer binary found at OPAMROOT/opam if present. This disables this
behaviour.
-q, --quiet
Disables --verbose.
--root=ROOT
Use ROOT as the current root path. This is equivalent to setting $OPAMROOT to ROOT.
--safe, --readonly
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. This is equivalent to set
environment variable $OPAMSAFE.
--solver=CMD
Specify the CUDF solver to use for resolving package installation problems. This is either a
predefined solver (this version of opam supports builtin-mccs+lp(), builtin-mccs+glpk,
builtin-dummy-z3-solver, builtin-0install, aspcud, mccs, aspcud-old, packup), or a custom command
that should contain the variables %{input}%, %{output}%, %{criteria}%, and optionally %{timeout}%.
This is equivalent to setting $OPAMEXTERNALSOLVER.
--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
Disable any external solver, and use the built-in one (this requires that opam has been compiled with
a built-in solver). This is equivalent to setting $OPAMNOASPCUD or $OPAMUSEINTERNALSOLVER.
-v, --verbose
Be more verbose. One -v shows all package commands, repeat to also display commands called internally
(e.g. tar, curl, patch etc.) Repeating n times is equivalent to setting $OPAMVERBOSE to "n".
--version
Show version information.
-w, --working-dir
Whenever updating packages that are bound to a local, version-controlled directory, update to the
current working state of their source instead of the last committed state, or the ref they are
pointing to. As source directory is copied as it is, if it isn't clean it may result on a opam build
failure. This only affects packages explicitly listed on the command-line. It can also be set with
$OPAMWORKINGDIR.
-y, --yes
Answer yes to all opam yes/no questions without prompting. See also --confirm-level. This is
equivalent to setting $OPAMYES to "true".
ENVIRONMENT
Opam makes use of the environment variables listed here. Boolean variables should be set to "0", "no",
"false" or the empty string to disable, "1", "yes" or "true" to enable.
OPAMALLPARENS surround all filters with parenthesis.
OPAMASSUMEDEPEXTS see option `--assume-depexts'.
OPAMAUTOREMOVE see remove option `--auto-remove'.
OPAMBESTEFFORT see option `--best-effort'.
OPAMBESTEFFORTPREFIXCRITERIA sets the string that must be prepended to the criteria when the
`--best-effort' option is set, and is expected to maximise the `opam-query' property in the solution.
OPAMBUILDDOC Removed in 2.1.
OPAMBUILDTEST Removed in 2.1.
OPAMCLI see option `--cli'.
OPAMCOLOR when set to always or never, sets a default value for the `--color' option.
OPAMCONFIRMLEVEL see option `--confirm-level`. OPAMCONFIRMLEVEL has priority over OPAMYES and OPAMNO.
OPAMCRITERIA specifies user preferences for dependency solving. The default value depends on the solver
version, use `config report' to know the current setting. See also option --criteria.
OPAMCUDFFILE save the cudf graph to file-actions-explicit.dot.
OPAMCUDFTRIM controls the filtering of unrelated packages during CUDF preprocessing.
OPAMCURL can be used to select a given 'curl' program. See OPAMFETCH for more options.
OPAMDEBUG see options `--debug' and `--debug-level'.
OPAMDEBUGSECTIONS if set, limits debug messages to the space-separated list of sections. Sections can
optionally have a specific debug level (for example, CLIENT:2 or CLIENT CUDF:2), but otherwise use
`--debug-level'.
OPAMDIGDEPTH defines how aggressive the lookup for conflicts during CUDF preprocessing is.
OPAMDOWNLOADJOBS sets the maximum number of simultaneous downloads.
OPAMDROPWORKINGDIR overrides packages previously updated with --working-dir on update. Without this
variable set, opam would keep them unchanged unless explicitly named on the command-line.
OPAMDRYRUN see option `--dry-run'.
OPAMEDITOR sets the editor to use for opam file editing, overrides $EDITOR and $VISUAL.
OPAMERRLOGLEN sets the number of log lines printed when a sub-process fails. 0 to print all.
OPAMEXTERNALSOLVER see option `--solver'.
OPAMFAKE see option `--fake'.
OPAMFETCH specifies how to download files: either `wget', `curl' or a custom command where variables
%{url}%, %{out}%, %{retry}%, %{compress}% and %{checksum}% will be replaced. Overrides the
'download-command' value from the main config file.
OPAMFIXUPCRITERIA same as OPAMUPGRADECRITERIA, but specific to fixup and reinstall.
OPAMIGNORECONSTRAINTS see install option `--ignore-constraints-on'.
OPAMIGNOREPINDEPENDS see option `--ignore-pin-depends'.
OPAMINPLACEBUILD see option `--inplace-build'.
OPAMJOBS sets the maximum number of parallel workers to run.
OPAMJSON log json output to the given file (use character `%' to index the files).
OPAMKEEPBUILDDIR see install option `--keep-build-dir'.
OPAMKEEPLOGS tells opam to not remove some temporary command logs and some backups. This skips some
finalisers and may also help to get more reliable backtraces.
OPAMLOCKED combination of `--locked' and `--lock-suffix' options.
OPAMLOGS logdir sets log directory, default is a temporary directory in /tmp
OPAMMAKECMD set the system make command to use.
OPAMMERGEOUT merge process outputs, stderr on stdout.
OPAMNO answer no to any question asked, see options `--no` and `--confirm-level`. OPAMNO is ignored if
either OPAMCONFIRMLEVEL or OPAMYES is set.
OPAMNOAGGREGATE with `opam admin check', don't aggregate packages.
OPAMNOASPCUD Deprecated.
OPAMNOAUTOUPGRADE disables automatic internal upgrade of repositories in an earlier format to the current
one, on 'update' or 'init'.
OPAMNOCHECKSUMS enables option --no-checksums when available.
OPAMNODEPEXTS disables system dependencies handling, see option `--no-depexts'.
OPAMNOENVNOTICE Internal.
OPAMNOSELFUPGRADE see option `--no-self-upgrade'
OPAMPINKINDAUTO sets whether version control systems should be detected when pinning to a local path.
Enabled by default since 1.3.0.
OPAMPRECISETRACKING fine grain tracking of directories.
OPAMPREPRO set this to false to disable CUDF preprocessing. Less efficient, but might help debugging
solver issue.
OPAMREPOSITORYTARRING internally store the repositories as tar.gz files. This can be much faster on
filesystems that don't cope well with scanning large trees but have good caching in /tmp. However this is
slower in the general case.
OPAMREQUIRECHECKSUMS Enables option `--require-checksums' when available (e.g. for `opam install').
OPAMRETRIES sets the number of tries before failing downloads.
OPAMREUSEBUILDDIR see option `--reuse-build-dir'.
OPAMROOT see option `--root'. This is automatically set by `opam env --root=DIR --set-root'.
OPAMROOTISOK don't complain when running as root.
OPAMSAFE see option `--safe'.
OPAMSHOW see option `--show'.
OPAMSKIPUPDATE see option `--skip-updates'.
OPAMSKIPVERSIONCHECKS bypasses some version checks. Unsafe, for compatibility testing only.
OPAMSOLVERALLOWSUBOPTIMAL (default `true') allows some solvers to still return a solution when they reach
timeout; while the solution remains assured to be consistent, there is no guarantee in this case that it
fits the expected optimisation criteria. If `true', opam willcontinue with a warning, if `false' a
timeout is an error. Currently only the builtin-z3 backend handles this degraded case.
OPAMSOLVERTIMEOUT change the time allowance of the solver. Default is 60.0, set to 0 for unlimited. Note
that all solvers may not support this option.
OPAMSTATS display stats at the end of command.
OPAMSTATUSLINE display a dynamic status line showing what's currently going on on the terminal. (one of
one of always, never or auto)
OPAMSTRICT fail on inconsistencies (file reading, switch import, etc.).
OPAMSWITCH see option `--switch'. Automatically set by `opam env --switch=SWITCH --set-switch'.
OPAMUNLOCKBASE see install option `--unlock-base'.
OPAMUPGRADECRITERIA specifies user preferences for dependency solving when performing an upgrade.
Overrides OPAMCRITERIA in upgrades if both are set. See also option --criteria.
OPAMUSEINTERNALSOLVER see option `--use-internal-solver'.
OPAMUSEOPENSSL Removed in 2.2.
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 macOS only.
OPAMVALIDATIONHOOK if set, uses the `%{hook%}' command to validate an opam repository update.
OPAMVERBOSE see option `--verbose'.
OPAMVERBOSEON see option --verbose-on
OPAMVERSIONLAGPOWER do not use.
OPAMWITHDEVSETUP see install option `--with-dev-setup'.
OPAMWITHDOC see install option `--with-doc'.
OPAMWITHTEST see install option `--with-test.
OPAMWORKINGDIR see option `--working-dir'.
OPAMYES see options `--yes' and `--confirm-level`. OPAMYES has priority over OPAMNO and is ignored if
OPAMCONFIRMLEVEL is set.
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.
CLI VERSION
All scripts and programmatic invocations of opam should use `--cli' in order to ensure that they work
seamlessly with future versions of the opam client. Additionally, blog posts or other documentation can
benefit, as it prevents information from becoming stale.
Although opam only supports roots (~/.opam/) for the current version, it does provide backwards
compatibility for its command-line interface.
Since CLI version support was only added in opam 2.1, use OPAMCLI to select 2.0 support (as opam 2.0 will
just ignore it), and `--cli=2.1' for 2.1 (or later) versions, since an environment variable controlling
the parsing of syntax is brittle. To this end, opam displays a warning if OPAMCLI specifies a valid
version other than 2.0, and also if `--cli=2.0' is specified.
The command-line version is selected by using the `--cli' option or the OPAMCLI environment variable.
`--cli' may be specified morethan once, where the last instance takes precedence. OPAMCLI is only
inspected if `--cli' is not given.
EXIT STATUS
As an exception to the following, the `exec' command returns 127 if the command was not found or couldn't
be executed, and the command's exit value otherwise.
0 Success, or true for boolean queries.
1 False. Returned when a boolean return value is expected, e.g. when running with --check, or for
queries like opam lint.
2 Bad command-line arguments, or command-line arguments pointing to an invalid context (e.g. file not
following the expected format).
5 Not found. You requested something (package, version, repository, etc.) that couldn't be found.
10 Aborted. The operation required confirmation, which wasn't given.
15 Could not acquire the locks required for the operation.
20 There is no solution to the user request. This can be caused by asking to install two incompatible
packages, for example.
30 Error in package definition, or other metadata files. Using --strict raises this error more often.
31 Package script error. Some package operations were unsuccessful. This may be an error in the packages
or an incompatibility with your system. This can be a partial error.
40 Sync error. Could not fetch some remotes from the network. This can be a partial error.
50 Configuration error. Opam or system configuration doesn't allow operation, and needs fixing.
60 Solver failure. The solver failed to return a sound answer. It can be due to a broken external
solver, or an error in solver configuration.
99 Internal error. Something went wrong, likely due to a bug in opam itself.
130 User interrupt. SIGINT was received, generally due to the user pressing Ctrl-C.
0 on success.
123 on indiscriminate errors reported on standard error.
124 on command line parsing errors.
125 on unexpected internal errors (bugs).
FURTHER DOCUMENTATION
See https://opam.ocaml.org/doc.
AUTHORS
David Allsopp <david@tarides.com>
Vincent Bernardoff <vb@luminar.eu.org>
Raja Boujbel <raja.boujbel@ocamlpro.com>
Kate Deplaix <kit-ty-kate@outlook.com>
Roberto Di Cosmo <roberto@dicosmo.org>
Thomas Gazagnaire <thomas@gazagnaire.org>
Louis Gesbert <louis.gesbert@ocamlpro.com>
Fabrice Le Fessant <Fabrice.Le_fessant@inria.fr>
Anil Madhavapeddy <anil@recoil.org>
Guillem Rieu <guillem.rieu@ocamlpro.com>
Ralf Treinen <ralf.treinen@pps.jussieu.fr>
Frederic Tuong <tuong@users.gforge.inria.fr>
SEE ALSO
opam(1)
BUGS
Check bug reports at https://github.com/ocaml/opam/issues.
Opam 2.3.0 OPAM-INIT(1)