--- name: "ocamlfind" section: "1" platform: "linux" package: "ocaml-findlib" version: "1.9.8-7" release: "Arch Linux 2026-11-01" platforms: ["linux"] url: "https://new.carta.tech/ocamlfind" --- # ocamlfind(1) \[Command-line interface of the Package manager\] ## NAME ocamlfind - \[Command-line interface of the Package manager\] ## SYNOPSIS ``` ocamlfind query [-help | other options] package_name ... or: ocamlfind ocamlc [-help | other options] file ... or: ocamlfind ocamlcp [-help | other options] file ... or: ocamlfind ocamlmktop [-help | other options] file ... or: ocamlfind ocamlopt [-help | other options] file ... or: ocamlfind ocamldoc [-help | other options] file ... or: ocamlfind ocamldep [-help | other options] file ... or: ocamlfind ocamlmklib [-help | other options] file ... or: ocamlfind ocamlbrowser [-help | other options] or: ocamlfind install [-help | other options] package_name file ... or: ocamlfind remove [-help | other options] package_name or: ocamlfind lint META or: ocamlfind list [-describe] or: ocamlfind printppx [-help | other options] package_name ... or: ocamlfind printconf [ variable ] or: ocamlfind package / command arg ... Optional toolchain selection by: ocamlfind -toolchain name ... ``` ## THE 'query' SUBCOMMAND ### Synopsis ``` ocamlfind query [ -predicates p | -format f | -long-format | -l | -i-format | -l-format | -a-format | -o-format | -p-format | -prefix p | -separator s | -suffix s | -pp | -descendants | -d | -recursive | -r -qe | -qo] package ... ``` ### Description This command looks packages up, sorts them optionally, and prints attributes of them. If the option -recursive (short: -r) is not specified, exactly the packages given on the command line are looked up; if -recursive is present, the packages and all their ancestors, or if -descendants (short: -d) is present, too, all their descendants are printed. Package lookup and the selection of the attributes of the packages can be modified by specifying predicates; without a -predicates option the empty set of predicates is used. Note that even the lookup is influenced by the set of actual predicates as the "requires" variables may be conditional. What is printed about a package depends on the specified format; there are a number of options that modify the format. Some formats denote sets of values (such as -format %a), in which case multiple output records are printed for every package. (It is even possible to specify formats denoting the Cartesian product of sets, such as -format %a%o, but this does not make sense.) Before the first output record the prefix is printed, and the suffix after the last record. Between two records the separator is printed. ### Options \-predicates *p* Sets the set of actual predicates. The argument *p* is a list of predicate names separated by commas and/or whitespace. If multiple -predicates options are given, the union of all specified sets is effectively used. \-format *f* Sets the format to the string *f*. Characters preceded by a percent sign are interpreted as placeholders; all other characters mean themselves. The defined placeholders are listed below. The default format is "%d". \-long-format or -l Sets the format such that all relevant variables are printed. \-i-format Same as -format "-I %d", i.e. directory options for ocamlc are printed. \-l-format Same as -format "-ccopt -L%d", i.e. directory options for the linker backend are printed. \-a-format Same as -format "%+a", i.e. archive file names are printed. \-o-format Same as -format "%o", i.e. linker options are printed. \-p-format Same as -format "%p", i.e. package names are printed. \-prefix *p* Sets the prefix that is printed before the first output record to the given string. The default prefix is the empty string. \-suffix *s* Sets the suffix that is printed after the last output record to the given string. The default suffix is the empty string. \-separator *s* Sets the separator that is printed between output records to the given string. The default separator is a linefeed character. \-recursive or -r Not only the packages given on the command line are queried but also all ancestors or descendants. If the option -descendants is specified, too, the descendants are printed, otherwise the ancestors. The packages are topologically sorted. \-descendants -d Instead of the ancestors the descendants of the given packages are queried. This option implies -recursive. \-pp Query preprocessor packages (camlp4 syntax extensions). Normally it is not needed to set -predicates, except you need the archives (then add -predicates byte). This option implies -recursive. \-qe Do not print most errors to stderr, just set the exit code \-qo Do not print the regular output. ### Placeholders meaningful in the -format option %% Replaced by a single percent sign %p Replaced by the package name %d Replaced by the package directory %m Replaced by the path to the META file (new since findlib-1.6) %D Replaced by the package description %v Replaced by the version string %a Replaced by the archive filename. If there is more than one archive, a separate output record is printed for every archive. %+a Like %a, but the filenames are converted to absolute paths ("+" and "@" notations are resolved) %A Replaced by the list of archive filenames. %+A Like %A, but the filenames are converted to absolute paths ("+" and "@" notations are resolved) %o Replaced by one linker option. If there is more than one option, a separate output record is printed for every option. %O Replaced by the list of linker options. %(*property*) Replaced by the value of the property named in parentheses, or the empty string if not defined. ## THE SUBCOMMANDS 'ocamlc', 'ocamlcp', 'ocamlopt', and 'ocamlmktop' ### Synopsis ``` ocamlfind ( ocamlc | ocamlcp | ocamlopt | ocamlmktop ) [ -package package-name-list | -linkpkg | -predicates pred-name-list | -dontlink package-name-list | -syntax pred-name-list | -ppopt camlp4-arg | -ppxopt package , arg | -dllpath-pkg package-name-list | -dllpath-all | -passopt arg | -passrest arg... | -only-show | standard-option ] file ... ``` ### Description These subcommands are drivers for the compilers with the same names, i.e. "ocamlfind ocamlc" is a driver for "ocamlc", and so on. The subcommands understand all documented options of the compilers (here called *standard-options*), but also a few more options. If these subcommands are invoked only with standard options, they behave as if the underlying compiler had been called directly. The extra options modify this. Internally, these subcommands transform the given list of options and file arguments into an invocation of the driven compiler. This transformation only adds options and files, and the relative order of the options and files passed directly is unchanged. If there are -package options, additional directory search specifiers will be included ("-I", and "-ccopt -I"), such that files of all named packages and all ancestors can be found. The -linkpkg option causes that the packages listed in the -package options and all necessary ancestors are linked in. This means that the archive files implementing the packages are inserted into the list of file arguments. As the package database is queried a set of predicates is needed. Most predicates are set automatically, see below, but additional predicates can be given by a -predicates option. If there is a -syntax option, the drivers assume that a preprocessor is to be used. In this case, the preprocessor command is built first in a preprocessor stage, and this command is passed to the compiler using the -pp option. The set of predicates in the preprocessor stage is different from the set in the compiler/linker stage. ### Options for compiling and linking Here, only the additional options not interpreted by the compiler but by the driver itself, and options with additional effects are explained. Some options are only meaningful for the preprocessor call, and are explained below. \-package *package-name-list* Adds the listed package names to the set of included packages. The package names may be separated by commas and/or whitespace. In the transformed command, for every package of the set of included packages and for any ancestor a directory search option is inserted after the already given options. This means that "-I" and "-ccopt -I" options are added for every package directory. \-linkpkg Causes that in the transformed command all archives of the packages specified by -packages and all their ancestors are added to the file arguments. More precisely, these archives are inserted before the first given file argument. Furthermore, "-ccopt -L" options for all package directories, and the linker options of the selected packages are added, too. Note that the archives are inserted in topological order while the linker options are added in reverse toplogical order. \-predicates *pred-name-list* Adds the given predicates to the set of actual predicates. The predicates must be separated by commas and/or whitespace. \-dontlink *package-name-list* This option modifies the behaviour of -linkpkg. Packages specified here and all ancestors are not linked in. Again the packages are separated by commas and/or whitespace. \-dllpath-pkg *package-name-list* For these packages -dllpath options are added to the compiler command. This may be useful when the ld.conf file is not properly configured. \-dllpath-all For all linked packages -dllpath options are added to the compiler command. This may be useful when the ld.conf file is not properly configured. \-passopt *arg* The argument *arg* is passed directly to the underlying compiler. This is needed to specify undocumented compiler options. \-passrest *arg...* All following arguments *arg...* are passed directly to the underlying compiler. This is needed to specify undocumented compiler options. \-only-show Only prints the constructed command (ocamlc/ocamlopt) to stdout, but does not execute the command. (This is for the unlikely event that you need a wrapper around ocamlfind.) \-verbose This standard option is interpreted by the driver, too. \-thread This standard option causes that the predicate "mt" is added to the set of actual predicates. If POSIX threads are available, the predicate "mt\_posix" is selected, too. If only VM threads are available, the predicate "mt\_vm" is included into the set, and the compiler switch is changed into -vmthread. Note that the presence of the "mt" predicate triggers special fixup of the dependency graph (see below). \-vmthread This standard option causes that the predicates "mt" and "mt\_vm" are added to the set of actual predicates. Note that the presence of the "mt" predicate triggers special fixup of the dependency graph (see below). \-p This standard option of "ocamlopt" causes that the predicate "gprof" is added to the set of actual predicates. ### Options for preprocessing The options relevant for the preprocessor are the following: \-package *package-name-list* These packages are considered while looking up the preprocessor arguments. (It does not cause problems that the same -package option is used for this purpose, because the set of predicates is different.) It is recommended to mention at least camlp4 here if the preprocessor is going to be used. \-syntax *pred-name-list* These predicates are assumed to be true in addition to the standard preprocessor predicates. See below for a list. \-ppopt *camlp4-arg* This argument is passed to the camlp4 call. \-ppxopt *package*,*arg* Add *arg* to the ppx preprocessor invocation specified via the "ppx" property in the META file of *package*. ### Predicates for compiling and linking byte The "byte" predicate means that one of the bytecode compilers is used. It is automatically included into the predicate set if the "ocamlc", "ocamlcp", or "ocamlmktop" compiler is used. native The "native" predicate means that the native compiler is used. It is automatically included into the predicate set if the "ocamlopt" compiler is used. toploop The "toploop" predicate means that the toploop is available in the linked program. This predicate is only set when the toploop is actually being executed, not when the toploop is created (this changed in version 1.0.4 of findlib). create\_toploop This predicate means that a toploop is being created (using ocamlmktop). mt The "mt" predicate means that the program is multi-threaded. It is automatically included into the predicate set if the -thread option is given. mt\_posix The "mt\_posix" predicate means that in the case "mt" is set, too, the POSIX libraries are used to implement threads. "mt\_posix" is automatically included into the predicate set if the variable "type\_of\_threads" in the META description of the "threads" package has the value "posix". This is normally the case if "findlib" is configured for POSIX threads. mt\_vm The "mt\_vm" predicate means that in the case "mt" is set, too, the VM thread emulation is used to implement multi-threading. gprof The "gprof" predicate means that in the case "native" is set, too, the program is compiled for profiling. It is automatically included into the predicate set if "ocamlopt" is used and the -p option is in effect. autolink The "autolink" predicate means that ocamlc is able to perform automatic linking. It is automatically included into the predicate set if ocamlc knows automatic linking (from version 3.00), but it is not set if the -noautolink option is set. syntax This predicate is set if there is a -syntax option. It is set both for the preprocessor and the compiler/linker stage, and it can be used to find out whether the preprocessor is enabled or not. ### Predicates for preprocessing preprocessor This predicate is always set while looking up the preprocessor arguments. It can be used to distinguish between the preprocessor stage and the compiler/linker stage. syntax This predicate is set if there is a -syntax option. It is set both for the preprocessor and the compiler/linker stage, and it can be used to find out whether the preprocessor is enabled or not. camlp4o This is the reserved predicate for the standard OCaml syntax. It can be used in the -syntax predicate list. camlp4r This is the reserved predicate for the revised OCaml syntax. It can be used in the -syntax predicate list. ### Special behaviour of 'ocamlmktop' As there is a special module Topfind that supports loading of packages in scripts, the "ocamlmktop" subcommand can add initialization code for this module. This extra code is linked into the executable if "findlib" is in the set of effectively linked packages. ### Fixup of the dependency graph for multi-threading For a number of reasons the presence of the "mt" predicate triggers that (1) the package "threads" is added to the list of required packages and (2) the package "threads" becomes prerequisite of all other packages (except of itself and a few hardcoded exceptions). The effect is that the options -thread and -vmthread automatically select the "threads" package, and that "threads" is inserted at the right position in the package list. ### Extended file naming At a number of places one can not only refer to files by absolute or relative path names, but also by extended names. These have two major forms: "+*name*" refers to the subdirectory *name* of the standard library directory, and "@*name*" refers to the package directory of the package *name*. Both forms can be continued by a path, e.g. "@netstring/netstring\_top.cma". You can use extended names: (1) With -I options, (2) as normal file arguments of the compiler, (3) in the "archive" property of packages. ### How to set the names of the compiler executables Normally, the OCaml bytecode compiler can be called under the name ocamlc. However, this is not always true; sometimes a different name is chosen. You can instruct ocamlfind to call executables with other names than ocamlc, ocamlopt, ocamlmktop, and ocamlcp. If present, the environment variable OCAMLFIND\_COMMANDS is interpreted as a mapping from the standard names to the actual names of the executables. It must have the following format: ``` standardname1 = actualname1 standardname2 = actualname2 ... ``` Example: You may set OCAMLFIND\_COMMANDS as follows: ``` OCAMLFIND_COMMANDS='ocamlc=ocamlc-3.00 ocamlopt=ocamlopt-3.00' export OCAMLFIND_COMMANDS ``` Alternatively, you can change the configuration file findlib.conf. ## THE SUBCOMMAND 'ocamlmklib' ### Synopsis ``` ocamlfind ocamlmklib [ -package package-name-list | -predicates pred-name-list | -dllpath-pkg package-name-list | -dllpath-all | -passopt arg | -passrest arg... | standard-option ] file ... ``` ### Description This is a wrapper around ocamlmklib, and creates library archives and DLLs. In addition to the standard options, one can use -package to add the search path of packages. Note that no predicates are set by default - the wrapper does not know whether this is about byte or native code linking. This wrapper is mostly provided for completeness. ## THE 'ocamldep' SUBCOMMAND ### Synopsis ``` ocamlfind ocamldep [-package package-name-list | -syntax pred-name-list | -ppopt camlp4-arg | -passopt arg | -passrest arg... | -verbose | standard-option ] file ... ``` ### Description This command is a driver for the tool ocamldep of the OCaml distribution. This driver is only useful in conjunction with the preprocessor camlp4; otherwise it does not provide more functions than ocamldep itself. ### Options Here, only the additional options not interpreted by ocamldep but by the driver itself, and options with additional effects are explained. \-package *package-name-list* The packages named here are only used to look up the preprocessor options. The package camlp4 should be specified anyway, but further packages that add capabilities to the preprocessor can also be passed. \-syntax *pred-name-list* The predicates that are in effect during the look-up of the preprocessor options. At least, either camlp4o (selecting the normal syntax), or camlp4r (selecting the revised syntax) should be specified. \-ppopt *camlp4-arg* An option that is passed through to the camlp4 call. \-passopt *arg* An option that is passed through to the ocamldep call. \-passrest *arg...* All further arguments are passed down to ocamldep unprocessed \-verbose Displays the resulting ocamldep command (for debugging) ### Example A typical way of using this driver: ``` ocamlfind ocamldep -package camlp4,xstrp4 -syntax camlp4r file1.ml file2.ml ``` This command outputs the dependencies of file1.ml and file2.ml, although these modules make use of the syntax extensions provided by xstrp4 and are written in revised syntax. ## THE 'ocamlbrowser' SUBCOMMAND ### Synopsis ``` ocamlfind ocamlbrowser [-package package-name-list | -all | -passopt arg -passrest ] ``` ### Description This driver calls the ocamlbrowser with package options. With -package, the specified packages are included into the search path of the browser, and the modules of these packages become visible (in addition to the standard library). The option -all causes that all packages are selected that are managed by findlib. As for other drivers, the options -passopt and -passrest can be used to pass arguments directly to the ocamlbrowser program. ## THE SUBCOMMAND 'ocamldoc' ### Synopsis ``` ocamlfind ocamldoc [ -package package-name-list | -predicates pred-name-list | -syntax pred-name-list | -ppopt camlp4-arg | standard-option ] file ... ``` ### Description This subcommand is a driver for ocamldoc. It undestands all options ocamldoc supports plus the mentioned findlib options. Basically, the -package options are translated into -I options, and the selected syntax options are translated into camlp4 options. ### Options Here, only the additional options not interpreted by ocamldep but by the driver itself, and options with additional effects are explained. \-package *package-name-list* Adds the listed package names to the set of included packages. The package names may be separated by commas and/or whitespace. In the transformed command, for every package of the set of included packages and for any ancestor a directory search option is inserted after the already given options. This means that "-I" options are added for every package directory. \-predicates *pred-name-list* Adds the given predicates to the set of actual predicates. The predicates must be separated by commas and/or whitespace. \-syntax *pred-name-list* The predicates that are in effect during the look-up of the preprocessor options. At least, either camlp4o (selecting the normal syntax), or camlp4r (selecting the revised syntax) should be specified. \-ppopt *camlp4-arg* An option that is passed through to the camlp4 call. ## THE 'install' SUBCOMMAND ### Synopsis ``` ocamlfind install [ -destdir directory ] [ -metadir directory ] [ -ldconf path ] [ -dont-add-directory-directive ] [ -patch-version string ] [ -patch-rmpkg name ] [ -patch-archives ] [ -dll ] [ -nodll ] [ -optional ] [ -add ] package_name file ... ``` ### Description This subcommand installs a new package either at the default location (see the variable destdir of findlib.conf), or in the directory specified by the -destdir option. This means that a new package directory is created and that the files on the command line are copied to this directory. It is required that a META file is one of the files copied to the target directory. Note that package directories should be flat (no subdirectories). Existing packages are never overwritten. It is possible to have a separate directory for all the META files. If you want that, you have either to set the variable metadir of findlib.conf, or to specify the -metadir option. In this case, the file called META is copied to the specified directory and renamed to META.p (where p is the package name), while all the other files are copied to the package directory as usual. Furthermore, the META file is modified such that the directory variable contains the path of the package directory. The option -dont-add-directory-directive prevents the installer from adding a directory variable. If there are files ending in the suffixes .so or .dll, the package directory will be added to the DLL configuration file ld.conf, such that the dynamic loader can find the DLL. The location of this file can be overridden by the -ldconf option. To turn this feature off, use "-ldconf ignore"; this causes that the ld.conf file is not modified. However, if there is a stublibs directory in site-lib, the DLLs are not installed in the package directory, but in this directory that is shared by all packages that are installed at the same location. In this case, the configuration file ld.conf is not modified, so you do not need to say "-ldconf ignore" if you prefer this style of installation. The options -dll and -nodll can be used to control exactly which files are considered as DLLs and which not. By default, the mentioned suffix rule is in effect: files ending in ".so" (Unix) or ".dll" (Windows) are DLLs. The switch -dll changes this, and all following files are considered as DLLs, regardless of their suffix. The switch -nodll expresses that the following files are not DLLs, even if they have a DLL-like suffix. For example, in the following call the files f1 and f2 are handled by the suffix rule; f3 and f4 are DLLs anyway; and f5 and f6 are not DLLs: ``` ocamlfind install p f1 f2 -dll f3 f4 -nodll f5 f6 ``` The switch -optional declares that all following files are optional, i.e. the command will not fail if files do not exist. The -patch options may be used to change the contents of the META files while it is being installed. The option -patch-version changes the contents of the top-level "version" variable. The option -patch-rmpkg removes the given subpackage. The option -patch-archives is experimental, in particular it removes all non-existing files from "archive" variables, and even whole subpackages if the archives are missing. The effect of -add is to add further files to an already installed packages. ## THE 'remove' SUBCOMMAND ### Synopsis ``` ocamlfind remove [ -destdir directory ] [ -metadir directory ] [ -ldconf path ] package_name ``` ### Description The package will removed if it is installed at the default location (see the variable destdir of findlib.conf). If the package resides at a different location, it will not be removed by default; however, you can pass an alternate directory for packages by the -destdir option. (This must be the same directory as specified at installation time.) Note that package directories should be flat (no subdirectories); this subcommand cannot remove deep package directories. If you have a separate directory for META files, you must either configure this directory by the metadir variable of findlib.conf, or by specifying the -metadir option. The command does not fail if the package and/or the META file cannot be located. You will get a warning only in this case. If the package directory is mentioned in the ld.conf configuration file for DLLs, it will be tried to remove this entry from the file. The location of this file can be overridden by the -ldconf option. To turn this feature off, use "-ldconf ignore"; this causes that the ld.conf file is not modified. If there is a stublibs directory, it is checked whether the package owns any of the files in this directory, and the owned files will be deleted. ## THE 'list' SUBCOMMAND ### Synopsis ``` ocamlfind list [-describe] ``` ### Description This command lists all packages in the search path. The option -describe outputs the package descriptions, too. ## THE 'printppx' SUBCOMMAND ### Synopsis ``` ocamlfind printppx [ -predicates pred-name-list ] [ -ppxopt package , arg ] package ... ``` ### Description This command prints the ppx preprocessor options as they would occur in an OCaml compiler invocation for the packages listed in the command. The output includes one "-ppx" option for each preprocessor. The possible options have the same meaning as for "ocamlfind ocamlc". The option "-predicates" adds assumed predicates and "-ppxopt *package*,*arg*" adds "*arg*" to the ppx invocation of package *package*. The output of "ocamlfind printppx" will contain quotes """ for ppx commands that contain space-separated arguments. In this case $(ocamlfind printppx ...) won't work as naively expected, because many shells (including bash and dash) perform field splitting on the result of command substitutions without honoring quotes. ## THE 'lint' SUBCOMMAND ### Synopsis ``` ocamlfind lint file ``` ### Description Checks the META file, and reports possible problems. ## THE 'printconf' SUBCOMMAND ### Synopsis ``` ocamlfind printconf [ conf | path | destdir | metadir | metapath | stdlib | ldconf ] ``` ### Description This command prints the effective configuration after reading the configuration file, and after applying the various environment variables overriding settings. When called without arguments, the command prints all configuration options in a human-readable form. When called with an argument, only the value of the requested option is printed without explaining texts: conf Prints the location of the configuration file findlib.conf path Prints the search path for packages. The members of the path are separated by linefeeds. destdir Prints the location where package are installed and removed by default. metadir Prints the location where META files are installed and removed (if the alternative layout is used). metapath Prints the path where the META file is installed for a fictive package. The name of the package is marked with '%s' in the path. For instance, this command could output "/some/path/%s/META" or "/some/path/META.%s", depending on the layout. stdlib Prints the location of the standard library. ldconf Prints the location of the ld.conf file ## THE SUBCOMMAND CALLING PACKAGE PROGRAMS ### Synopsis ``` ocamlfind pkg / cmd argument ... ``` ### Description This subcommand is useful to call programs that are installed in package directories. It looks up the directory for *pkg* and calls the command named *cmd* in this directory. The remaining arguments are passed to this command. argv(0) contains the absolute path to the command, and argv(1) and the following argv entries contain the arguments. The working directory is not changed. Example: To call the program "x" that is installed in package "p", with arguments "y" and "z", run: ``` ocamlfind p/x y z ``` ## CONFIGURATION FILE, ENVIRONMENT VARIABLES The configuration file and environment variables are documented in the manual page for findlib.conf. ## HOW TO SET THE TOOLCHAIN ### Synopsis ``` ocamlfind -toolchain name ... ``` ### Description The -toolchain option can be given before any other command, e.g. ``` ocamlfind -toolchain foo ocamlc -c file.ml ``` compiles file.ml with toolchain "foo". By selecting toolchains one can switch to different command sets. For instance, the toolchain "foo" may consist of a patched ocamlc compiler. See findlib.conf how to configure toolchains.