1opam-switch(1) Opam Manual opam-switch(1)
2
6 opam-switch - Manage multiple installation prefixes.
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9 opam switch [OPTION]... [COMMAND] [ARG]...
10
12 This command is used to manage "switches", which are independent
13 installation prefixes with their own compiler and sets of installed and
14 pinned packages. This is typically useful to have different versions of
15 the compiler available at once.
16 Use opam switch create to create a new switch, and opam switch set to
18 set the currently active switch. Without argument, lists installed
19 switches, with one switch argument, defaults to set.
20 Switch handles SWITCH can be either a plain name, for switches that
22 will be held inside ~/.opam, or a directory name, which in that case is
23 the directory where the switch prefix will be installed, as _opam. Opam
24 will automatically select a switch by that name found in the current
25 directory or its parents, unless OPAMSWITCH is set or --switch is
26 specified. When creating a directory switch, if package definitions are
27 found locally, the user is automatically prompted to install them after
28 the switch is created unless --no-install is specified.
29 opam switch set sets the default switch globally, but it is also
31 possible to select a switch in a given shell session, using the
32 environment. For that, use eval $(opam env --switch=SWITCH
33 --set-switch).
34
36 Without argument, defaults to list.
37 SWITCH
39 With a SWITCH argument, defaults to set SWITCH.
40 create SWITCH [COMPILER]
42 Create a new switch, and install the given compiler there. SWITCH
43 can be a plain name, or a directory, absolute or relative, in which
44 case a local switch is created below the given directory. COMPILER,
45 if omitted, defaults to SWITCH if it is a plain name, unless
46 --packages or --empty is specified. When creating a local switch,
47 and none of these options are present, the compiler is chosen
48 according to the configuration default (see opam-init(1)). If the
49 chosen directory contains package definitions, a compatible
50 compiler is searched within the default selection, and the packages
51 will automatically get installed.
52 set SWITCH
54 Set the currently active switch, among the installed switches.
55 remove SWITCH
57 Remove the given switch from disk.
58 export FILE
60 Save the current switch state to a file. If --full is specified, it
61 includes the metadata of all installed packages
62 import FILE
64 Import a saved switch state. If --switch is specified and doesn't
65 point to an existing switch, the switch will be created for the
66 import.
67 reinstall [SWITCH]
69 Reinstall the given compiler switch and all its packages.
70 list
72 Lists installed switches.
73 list-available [PATTERN]
75 Lists base packages that can be used to create a new switch, i.e.
76 packages with the compiler flag set. If no pattern is supplied, all
77 versions are shown.
78 show
80 Prints the name of the current switch.
81 set-base PACKAGES
83 Sets the packages forming the immutable base for the selected
84 switch, overriding the current setting.
85 set-description STRING
87 Sets the description for the selected switch
88 link SWITCH [DIR]
90 Sets a local alias for a given switch, so that the switch gets
91 automatically selected whenever in that directory or a descendant.
92 install SWITCH
94 Deprecated alias for 'create'.
95
97 --deps-only
98 When creating a local switch in a project directory (i.e. a
99 directory containing opam package definitions), install the
100 dependencies of the project but not the project itself.
101 --description=STRING
103 Attach the given description to a switch when creating it. Use the
104 set-description subcommand to modify the description of an existing
105 switch.
106 --empty
108 Allow creating an empty (without compiler) switch.
109 --full
111 When exporting, include the metadata of all installed packages,
112 allowing to re-import even if they don't exist in the repositories
113 (the default is to include only the metadata of pinned packages).
114 -j JOBS, --jobs=JOBS
116 Set the maximal number of concurrent jobs to use. The default value
117 is calculated from the number of cores. You can also set it using
118 the $OPAMJOBS environment variable.
119 --no-install
121 When creating a local switch, don't look for any local package
122 definitions to install.
123 --no-switch
125 Don't automatically select newly installed switches.
126 --packages=PACKAGES
128 When installing a switch, explicitly define the set of packages to
129 set as the compiler.
130 --repositories=REPOS
132 When creating a new switch, use the given selection of repositories
133 instead of the default. REPOS should be a comma-separated list of
134 either already registered repository names (configured through e.g.
135 opam repository add --dont-select), or NAME=URL bindings, in which
136 case NAME should not be registered already to a different URL, and
137 the new repository will be registered. See opam repository for more
138 details. This option also affects list-available.
139 -s, --short
141 Output raw lists of names, one per line, skipping any details.
142
144 -b, --keep-build-dir
145 Keep the build directories after compiling packages. This is
146 equivalent to setting $OPAMKEEPBUILDDIR to "true".
147 -d, --with-doc, --build-doc
149 Build the package documentation. This only affects packages listed
150 on the command-line. The --build-doc form is deprecated as this
151 does also installation. This is equivalent to setting $OPAMWITHDOC
152 (or the deprecated $OPAMBUILDDOC) to "true".
153 --dry-run
155 Simulate the command, but don't actually perform any changes.
156 --fake
158 This option registers the actions into the opam database, without
159 actually performing them. WARNING: This option is dangerous and
160 likely to break your opam environment. You probably want
161 `--dry-run'. You've been warned.
162 --ignore-constraints-on[=PACKAGES] (default=)
164 Forces opam to ignore version constraints on all dependencies to
165 the listed packages. This can be used to test compatibility, but
166 expect builds to break when using this. Note that version
167 constraints on optional dependencies and conflicts are unaffected.
168 --inplace-build
170 When compiling a package which has its source bound to a local
171 directory, process the build and install actions directly in that
172 directory, rather than in a clean copy handled by opam. This only
173 affects packages that are explicitly listed on the command-line.
174 This is equivalent to setting $OPAMINPLACEBUILD to "true".
175 --locked[=SUFFIX] (default=locked)
177 In commands that use opam files found from pinned sources, if a
178 variant of the file with an added .SUFFIX extension is found (e.g.
179 foo.opam.locked besides foo.opam), that will be used instead. This
180 is typically useful to offer a more specific set of dependencies
181 and reproduce similar build contexts, hence the name. The opam lock
182 plugin can be used to generate such files, based on the versions of
183 the dependencies currently installed on the host. This is
184 equivalent to setting the $OPAMLOCK environment variable. Note that
185 this option doesn't generally affect already pinned packages.
186 -m MAKE, --make=MAKE
188 Use MAKE as the default 'make' command. Deprecated: use opam config
189 set[-global] make MAKE instead. Has no effect if the make variable
190 is defined.
191 --no-checksums
193 Do not verify the checksum of downloaded archives.This is
194 equivalent to setting $OPAMNOCHECKSUMS to "true".
195 --require-checksums
197 Reject the installation of packages that don't provide a checksum
198 for the upstream archives. This is equivalent to setting
199 $OPAMREQUIRECHECKSUMS to "true".
200 --reuse-build-dir
202 Reuse existing build directories (kept by using --keep-build-dir),
203 instead of compiling from a fresh clone of the source. This can be
204 faster, but also lead to failures if the build systems of the
205 packages don't handle upgrades of dependencies well. This is
206 equivalent to setting $OPAMREUSEBUILDDIR to "true".
207 --show-actions
209 Call the solver and display the actions. Don't perform any changes.
210 --skip-updates
212 When running an install, upgrade or reinstall on source-pinned
213 packages, they are normally updated from their origin first. This
214 flag disables that behaviour and will keep them to their version in
215 cache.
216 -t, --with-test, --build-test
218 Build and run the package unit-tests. This only affects packages
219 listed on the command-line. The --build-test form is deprecated as
220 this also affects installation. This is equivalent to setting
221 $OPAMWITHTEST (or the deprecated $OPAMBUILDTEST) to "true".
222 --unlock-base
224 Allow changes to the packages set as switch base (typically, the
225 main compiler). Use with caution.
226
228 These options are common to all commands.
229 --best-effort
231 Don't fail if all requested packages can't be installed: try to
232 install as many as possible. Note that not all external solvers may
233 support this option (recent versions of aspcud or mccs should).
234 --color=WHEN
236 Colorize the output. WHEN must be one of `always', `never' or
237 `auto'.
238 --criteria=CRITERIA
240 Specify user preferences for dependency solving for this run.
241 Overrides both $OPAMCRITERIA and $OPAMUPGRADECRITERIA. For details
242 on the supported language, and the external solvers available, see
243 http://opam.ocaml.org/doc/Specifying_Solver_Preferences.html. A
244 general guide to using solver preferences can be found at
245 http://www.dicosmo.org/Articles/usercriteria.pdf.
246 --cudf=FILENAME
248 Debug option: Save the CUDF requests sent to the solver to
249 FILENAME-<n>.cudf.
250 --debug
252 Print debug message to stderr. This is equivalent to setting
253 $OPAMDEBUG to "true".
254 --debug-level=LEVEL
256 Like --debug, but allows specifying the debug level (--debug sets
257 it to 1). Equivalent to setting $OPAMDEBUG to a positive integer.
258 --git-version
260 Print the git version of opam, if set (i.e. you are using a
261 development version), and exit.
262 --help[=FMT] (default=auto)
264 Show this help in format FMT. The value FMT must be one of `auto',
265 `pager', `groff' or `plain'. With `auto', the format is `pager` or
266 `plain' whenever the TERM env var is `dumb' or undefined.
267 --ignore-pin-depends
269 Ignore extra pins required by packages that get pinned, either
270 manually through opam pin or through opam install DIR. This is
271 equivalent to setting IGNOREPINDEPENDS=true.
272 --json=FILENAME
274 Save the results of the opam run in a computer-readable file. If
275 the filename contains the character `%', it will be replaced by an
276 index that doesn't overwrite an existing file. Similar to setting
277 the $OPAMJSON variable.
278 --no-auto-upgrade
280 When configuring or updating a repository that is written for an
281 earlier opam version (1.2), opam internally converts it to the
282 current format. This disables this behaviour. Note that
283 repositories should define their format version in a 'repo' file at
284 their root, or they will be assumed to be in the older format. It
285 is, in any case, preferable to upgrade the repositories manually
286 using opam admin upgrade [--mirror URL] when possible.
287 --no-self-upgrade
289 Opam will replace itself with a newer binary found at OPAMROOT/opam
290 if present. This disables this behaviour.
291 -q, --quiet
293 Disables --verbose.
294 --root=ROOT
296 Use ROOT as the current root path. This is equivalent to setting
297 $OPAMROOT to ROOT.
298 --safe, --readonly
300 Make sure nothing will be automatically updated or rewritten.
301 Useful for calling from completion scripts, for example. Will fail
302 whenever such an operation is needed ; also avoids waiting for
303 locks, skips interactive questions and overrides the $OPAMDEBUG
304 variable.
305 --solver=CMD
307 Specify the CUDF solver to use for resolving package installation
308 problems. This is either a predefined solver (this version of opam
309 supports builtin-mccs+lp(), builtin-mccs+glpk, aspcud, mccs,
310 aspcud-old, packup), or a custom command that should contain the
311 variables %{input}%, %{output}%, %{criteria}%, and optionally
312 %{timeout}%.
313 --strict
315 Fail whenever an error is found in a package definition or a
316 configuration file. The default is to continue silently if
317 possible.
318 --switch=SWITCH
320 Use SWITCH as the current compiler switch. This is equivalent to
321 setting $OPAMSWITCH to SWITCH.
322 --use-internal-solver, --no-aspcud
324 Disable any external solver, and use the built-in one (this
325 requires that opam has been compiled with a built-in solver).
326 -v, --verbose
328 Be more verbose. One -v shows all package commands, repeat to also
329 display commands called internally (e.g. tar, curl, patch etc.)
330 Repeating n times is equivalent to setting $OPAMVERBOSE to "n".
331 --version
333 Show version information.
334 -w, --working-dir
336 Whenever updating packages that are bound to a local,
337 version-controlled directory, update to the current working state
338 of their source instead of the last committed state, or the ref
339 they are pointing to. This only affects packages explicitly listed
340 on the command-line.
341 -y, --yes
343 Answer yes to all yes/no questions without prompting. This is
344 equivalent to setting $OPAMYES to "true".
345
347 Opam makes use of the environment variables listed here. Boolean
348 variables should be set to "0", "no", "false" or the empty string to
349 disable, "1", "yes" or "true" to enable.
350 OPAMCOLOR, when set to always or never, sets a default value for the
352 --color option.
353 OPAMCRITERIA specifies user preferences for dependency solving. The
355 default value depends on the solver version, use `config report` to
356 know the current setting. See also option --criteria
357 OPAMCURL can be used to select a given 'curl' program. See OPAMFETCH
359 for more options.
360 OPAMDEBUG see options `--debug' and `--debug-level'.
362 OPAMDOWNLOADJOBS sets the maximum number of simultaneous downloads.
364 OPAMERRLOGLEN sets the number of log lines printed when a sub-process
366 fails. 0 to print all.
367 OPAMEXTERNALSOLVER see option `--solver'.
369 OPAMFETCH specifies how to download files: either `wget', `curl' or a
371 custom command where variables %{url}%, %{out}%, %{retry}%,
372 %{compress}% and %{checksum}% will be replaced. Overrides the
373 'download-command' value from the main config file.
374 OPAMJOBS sets the maximum number of parallel workers to run.
376 OPAMJSON log json output to the given file (use character `%' to index
378 the files)
379 OPAMLOCK see option `--lock'.
381 OPAMNOAUTOUPGRADE disables automatic internal upgrade of repositories
383 in an earlier format to the current one, on 'update' or 'init'.
384 OPAMKEEPLOGS tells opam to not remove some temporary command logs and
386 some backups. This skips some finalisers and may also help to get more
387 reliable backtraces
388 OPAMLOCKRETRIES sets the number of tries after which OPAM gives up
390 acquiring its lock and fails. <= 0 means infinite wait.
391 OPAMNO answer no to any question asked.
393 OPAMNOASPCUD see option `--no-aspcud'.
395 OPAMNOSELFUPGRADE see option `--no-self-upgrade'.
397 OPAMPINKINDAUTO sets whether version control systems should be detected
399 when pinning to a local path. Enabled by default since 1.3.0.
400 OPAMREQUIRECHECKSUMS Enables option `--require-checksums' when
402 available (e.g. for `opam install`).
403 OPAMRETRY sets the number of tries before failing downloads.
405 OPAMROOT see option `--root'. This is automatically set by `opam env
407 --root=DIR --set-root'.
408 OPAMROOTISOK don't complain when running as root.
410 OPAMSAFE see option `--safe'
412 OPAMSKIPVERSIONCHECKS bypasses some version checks. Unsafe, for
414 compatibility testing only.
415 OPAMSOLVERTIMEOUT change the time allowance of the solver. Default is
417 60.0, set to 0 for unlimited. Note that all solvers may not support
418 this option.
419 OPAMSTATUSLINE display a dynamic status line showing what's currently
421 going on on the terminal. (one of one of `always', `never' or `auto')
422 OPAMSWITCH see option `--switch'. Automatically set by `opam env
424 --switch=SWITCH --set-switch'.
425 OPAMUPGRADECRITERIA specifies user preferences for dependency solving
427 when performing an upgrade. Overrides OPAMCRITERIA in upgrades if both
428 are set. See also option --criteria
429 OPAMUSEINTERNALSOLVER see option `--use-internal-solver'.
431 OPAMUTF8 use UTF8 characters in output (one of one of `always', `never'
433 or `auto'). By default `auto', which is determined from the locale).
434 OPAMUTF8MSGS use extended UTF8 characters (camels) in opam messages.
436 Implies OPAMUTF8. This is set by default on OSX only.
437 OPAMVAR_var overrides the contents of the variable var when
439 substituting `%{var}%` strings in `opam` files.
440 OPAMVAR_package_var overrides the contents of the variable package:var
442 when substituting `%{package:var}%` strings in `opam` files.
443 OPAMVERBOSE see option `--verbose'.
445 OPAMYES see option `--yes'.
447
449 As an exception to the following, the `exec' command returns 127 if the
450 command was not found or couldn't be executed, and the command's exit
451 value otherwise.
452 0 Success, or true for boolean queries.
454 1 False. Returned when a boolean return value is expected, e.g. when
456 running with --check, or for queries like opam lint.
457 2 Bad command-line arguments, or command-line arguments pointing to
459 an invalid context (e.g. file not following the expected format).
460 5 Not found. You requested something (package, version, repository,
462 etc.) that couldn't be found.
463 10 Aborted. The operation required confirmation, which wasn't given.
465 15 Could not acquire the locks required for the operation.
467 20 There is no solution to the user request. This can be caused by
469 asking to install two incompatible packages, for example.
470 30 Error in package definition, or other metadata files. Using
472 --strict raises this error more often.
473 31 Package script error. Some package operations were unsuccessful.
475 This may be an error in the packages or an incompatibility with
476 your system. This can be a partial error.
477 40 Sync error. Could not fetch some remotes from the network. This can
479 be a partial error.
480 50 Configuration error. Opam or system configuration doesn't allow
482 operation, and needs fixing.
483 60 Solver failure. The solver failed to return a sound answer. It can
485 be due to a broken external solver, or an error in solver
486 configuration.
487 99 Internal error. Something went wrong, likely due to a bug in opam
489 itself.
490 130 User interrupt. SIGINT was received, generally due to the user
492 pressing Ctrl-C.
493
495 See https://opam.ocaml.org/doc.
496
498 Vincent Bernardoff <vb@luminar.eu.org>
499 Raja Boujbel <raja.boujbel@ocamlpro.com>
500 Roberto Di Cosmo <roberto@dicosmo.org>
501 Thomas Gazagnaire <thomas@gazagnaire.org>
502 Louis Gesbert <louis.gesbert@ocamlpro.com>
503 Fabrice Le Fessant <Fabrice.Le_fessant@inria.fr>
504 Anil Madhavapeddy <anil@recoil.org>
505 Guillem Rieu <guillem.rieu@ocamlpro.com>
506 Ralf Treinen <ralf.treinen@pps.jussieu.fr>
507 Frederic Tuong <tuong@users.gforge.inria.fr>
508
510 Check bug reports at https://github.com/ocaml/opam/issues.
511Opam 2.0.1 opam-switch(1)