The "findlib" software provides a scheme to manage reusable software components in the form of libraries, and includes tools that support this scheme. A library installed as a findlib component is also called a package. The point is that the findlib scheme allows it to store metainformation about the library, especially how it can be used in programs. The packages are kept in the filesystem hierarchy, but the directory structure is defined by findlib, and there is no way to deviate from this standard. The library contains functions to look the directory up that stores a package, to query metainformation about a package, and to retrieve dependency information about multiple packages. There is also a tool that allows the user to enter queries on the command-line. In order to simplify compilation and linkage, there are new frontends of the various OCaml compilers that can directly deal with packages.
It is important to understand that findlib is not a general-purpose package manager (like rpm for Linux), and does not support the management of arbitrary files, but only O'Caml libraries. However, there are lots of special functions for libraries. findlib is more comparable with Gnome's pkg-config and Perl's MakeMaker, but of course there are language-specific differences.
The metainformation includes:
The necessary command-line arguments to use a library.
Dependencies on other packages.
Version strings.
These data can be conditional. Possible conditions are certain environmental settings, such as whether the bytecode or the native code compiler is used, or whether the application is multi-threaded. It is also possible that a package behaves differently when a certain other package is selected.
There is special support for scripts. It is possible to load libraries into toploops, including all dependent libraries, with only one command.
Findlib has been developed since March 1999, and has matured for more than four years until the release of version 1.0. One of the important questions during this long period of development was which features are necessary and which not. The result is a utility that follows still simple concepts, but is flexible enough to allow even the description of complex libraries and complex interdependencies.
</sect1> <sect1> <title>Documentation</title>See the file QUICKSTART for the most important findlib commands.
There is a User's Guide introducing into the concepts of findlib, especially explaining how to create packages.
The Reference Manual describes commands, directory structure, configuration files, and library routines in detail.
</sect1> <sect1> <title>Installation</title>See the file INSTALL.
</sect1> <sect1> <title>Download</title>The current version is announced in the Objective Caml Link Database.
</sect1> <sect1> <title>Copyright and License Conditions</title>Findlib is copyright 1999-2012 by Gerd Stolpmann. See the file LICENSE for the MIT/X11 style license conditions. Contact me at gerd@gerd-stolpmann.de in case of questions.
</sect1> <sect1> <title>List of Changes</title>1.8.0: Fix reinstallation of "num" for OCaml-4.06.
Fix build with OCaml-4.07.
The installation of graphics/META is now optional.
Fix "ocamlfind query -d".
The environment variable OCAMLFIND_IGNORE_DUPS_IN is now interpreted as a list of directories.
Packages for "ocamlfind query" may now be separated by commas, too.
New "warning" property for packages.
Forgetting to pass -thread/-vmthread only prints a warning now, but doesn't stop the build.
For dealing with case-sensitive filesystems it is now only tried to match ASCII characters, but not encoding-dependent characters.
1.7.3: Fix regarding num-top: this library is now also optional, as num.
1.7.2: Trying to protect against failures when several package installs are done in parallel.
New subpackage "findlib.top" for the toploop (Jeremie Dimino).
The "num" library is now optional.
Shell scripts are started via "sh" command when there is no /bin/sh (ygrek)
1.7.1: added missing file to tarball
1.7.0: New command "ocamlfind printppx" that outputs how the ppx preprocessor would be called (Hendrik Tews).
Support for the raw_spacetime library that comes with OCaml 4.04 (Gerd Stolpmann with help from Mark Shinwell).
Require that ocamlc and ocamlc.opt are installed to the same directory for emitting the "opt" setting in the generated config file - same for ocamlopt.opt, ocamldep.opt, ocamldoc.opt.
1.6.3:Fix: "ocamlfind printconf" respects the environment variable OCAMLFIND_CONF (reported by Andre)
Build with -opaque (reported by hhugo)
Preliminary support for native toplevel so far the toplevel is implemented symmetrically to the bytecode case (this is not correct in vanilla ocaml)
New options: ocamlfind query -qe -qo
1.6.2:Uninstalling findlib no longer uninstalls the ocamlbuild library by accident (Gabriel Scherer, Edwin Török)
Adding an "ocamldoc" library, providing the cmi's for ocamldoc plugins (suggested by Armaël Guéneau)
Support for OCaml-4.03: recognize that the new -color option has an argument (reported by Guillaume Bury)
1.6.1: Just an important doc fix.
1.6.0: Adding support for dynamically loading packages (François Bobot): new "plugin" variable, new Fl_dynload module.
New command "ocamlfind lint" for checking META files (François Bobot).
Also support MSYS_NT on Windows. Permit spaces in install paths (Christophe Troestler).
Allow to query the location of the META file of a package: "ocamlfind query -format '%m'" (Gerd Stolpmann).
Get the install path for the META file of packages: "ocamlfind printconf metapath" (Gerd Stolpmann).
1.5.6: for MSVC build fixing bad filename suffix (Dmitry Bely).
The switch -only-show did not work as described. (Error report from Bob Atkey.)
Also support mingw64 as system type (Matthieu Dubuget).
1.5.5: fixes a build problem for BSD systens
1.5.4: New ppxopt META variables (Peter Zotov).
Support for OCAMLFIND_TOOLCHAIN environment variable (Peter Zotov).
1.5.3: The installation of "bytes" respects now $prefix and the configured destination.
New option -pp for "ocamlfind query", to get preprocessor packages.
Updated the compatibility Bytes module to support extend, init, mapi, blit_string (Gabriel Scherer).
1.5.2: support for the query formats "%+a" and "%+A".
Fix: the "ppx" property is now also path-expanded when interpreted in a toploop.
Fix: implicit "ppx" is not path-expanded anymore.
Fix: Build bytes.cmxs only if natdynlink is enabled (Andy Ray).
1.5.1: includes a file that was missing in 1.5
1.5: Including the "bytes" package that is either a compat package for ocaml < 4.02 or a fake package for ocaml >= 4.02. The package aims at helping to support the transition to the new "bytes" type for mutable strings.
Also installing findlib.cmxs if OCaml supports it.
Allowing to disable camlp4 (in prep for OCaml-4.02).
The "ppx" package property can be specified for constructing ppx-type preprocessors (patches from Peter Zotov).
1.4.1:ocamldoc: The order of -ppopt arguments was changed by ocamlfind, which is not correct. (Sylvain Le Gall and Jérémie Dimino.)
1.4: Fixed performance bug when many arguments need to be processed (Jérôme Vouillon).
Auto-configuring ocamldoc.opt if it is found (Christopher Zimmermann).
New config switch -no-custom to prevent that "ocamlfind" is linked in custom-runtime mode (bytecode only) (Christopher Zimmermann).
The library dbm is no longer part of OCaml, and now optional in findlib (Ashish Argawal).
Support for ocamloptp.
New function Topfind.log for controlling the verbosity (Jeremie Dimino).
Rewritten Fl_metascanner without camlp4 (patch from Gabriel Scherer)
1.3.3: OCaml-4: using the new #remove_directory directive if present.
Better compatibility with the OCaml version from Homebrew.
1.3.2: Handling of empty arguments (Wojciech Meyer).
Added entry for camlp4.fulllib.
New switch -add for "ocamlfind install" (Hans Ole Rafaelsen).
Further fixes for ocaml-4.00.
Fixing the recognition of double .cmi interface files.
Fixing -dontlink (it is now deeply interpreted).
1.3.1: Fixing a bug with ocamlmklib that slipped through in 1.3.0
1.3.0: Fixes for ocaml-4.00 (especially topfind).
Emitting an error if the configuration file does not exist.
Emitting a warning if the selected toolchain does not exist.
camlp4 is referenced by "+camlp4" in META.
Including the sources for the documentation in the tarball.
License change (simplification) for num_top_printers.mli.
Fix ocamlmklib wrapper: processing contracted args (like -L/dir) correctly.
Many wrappers get a new option -passrest instructing to pass all remaining options on the command-line unchanged to the invoked tool.
Prettified -help output.
1.2.8: Adding support for ocamlmklib (B. Meurer's patches)
Fix for win32 in the configure script.
1.2.7: Fix: if a META file defines several packages, and one of the packages has a broken dependency, ocamlfind used to report all errors even if the broken packages were not used. This is now changed - broken subpackages are ignored when they are not needed, in the same way as broken top-level packages are ignored when not needed. (Thanks to Sylvain Le Gall for reporting the problem.)
Added -thread and -vmthread switches to "ocamlfind ocamldoc". These actually only add the right predicates. (Thanks to Vladimir Ivanov for pointing this problem out.)
Package warnings can be emitted by "ocamlfind ocamldoc".
1.2.6: adding META for ocamlbuild.
Fixes for MinGW/MSYS platform.
Improved messages.
1.2.5: Fix: Again CR deletion... Turns out some OS do not understand '\r' but only '\015' (thanks to Isaiah Weiner).
Support for Win64 (untested; thanks to David Allsopp).
ocamlfind no longer emits auto-generated -ccopt options. These tend to accumulate, and it is possible that for large projects the maximum command line length is exceeded. Current versions of the O'Caml compilers do not need these extra -ccopt anyway, so this code is completely dropped.
1.2.4: Fix: Bigarray needs unix (Thanks to Markus Mottl).
Fix: In the version of camlp4 provided by O'Caml 3.11 various libraries do not contain dynlink anymore. Because of this, dynlink becomes a prerequisite of camlp4. (Thanks to Martin Jambon).
Attempt: Fixing the space issue for paths (Win32). It is unclear whether it is solved. (Thanks to Christophe Troestler).
1.2.3: Solving the CR deletion differently, to make OS X happy.
1.2.2: Fix: Problem with CR character (Cygwin) (Thanks to David Allsopp).
Fix: Case-insensitive filesystems (partially solved) (Thanks to David Allsopp).
Fix: File name with backslashes at the end (Win32; thanks to Dmitry Grebeniuk).
1.2.1: Fix: Camlp4 rules now activate the stream parser extension
1.2: Fix in build scripts: Prepending $(prefix) when installing safe_camlp4 (thanks to Daniel Janus)
Non-existing -I directories are ignored (thanks to Nicolas Pouillard)
A script to create a MacOS X package (thanks to Pietro Abate)
Better support for Windows (with help from Robert Roessler and David Allsopp)
Support for camlp4 on O'Caml 3.10
Fix: "ocamlfind install" with "-patch" option writes now correct META file for the case that subpackages occur
Adding environment variable OCAMLFIND_IGNORE_DUPS_IN to reduce the number of warnings ocamlfind emits
1.1.2: Bugfix in the META parser: Backslashes are now correctly parsed. (Thanks to Martin Jambon for finding this problem.)
Fixes for platforms that do not support dynamic loading of DLLs.
Fixed extraction of camlp4 parameters from packages.
1.1.1: Bugfixes only: Fixed detection of threading model for O'Caml 3.09. Fixed alternate configuration files.
1.1: Automatic detection of standard compiler options.
Liberated the checks whether a package is already installed.
The .opt compilers are entered into findlib.conf if available.
New: "install" has -optional switch for optional files.
New: "install" has -patch-version to patch the version into the installed META file.
New: "install" has -patch-rmpkg to remove subpackages from the installed META file.
New: "install" has -patch-archives which removes non-existing files from "archive" variables. This is experimental.
New: subpackages can be disabled by exists_if.
New: Support for toolchains.
Fix for "remove": -destdir works again.
Fix for "call": CTRL-C works when calling interactive commands.
Fix for preprocessor packages: Dependencies on normal packages are resolved.
1.0.4: Fix: In previous versions, "ocamlmktop" set the "toploop" predicate. It turned out, however, that the toploops generated in this way did not work properly. For this reason, "ocamlmktop" does not set "toploop" any more for link time, but instead a new predicate "create_toploop". When the toploop is executed, the predicate "toploop" is again added.
1.0.3: Fix: The relative position of "-cclib -l" options on the command line is preserved. In previous versions, these options were moved to the beginning of the argument list. This did not work for static link editing; dynamic link editing was not affected.
Fix: The automatic fixup of "threads" dependencies works again. In the previous version, this was broken.
Addition: -format '%(name)' for ocamlfind query.
Some minor improvements of the documentation.
1.0.2: Fix: The alternate package layout did not fully work. This is repaired now, and there are some clarifications about relative directory paths in the documentation.
1.0.1: Fix: Forgot to install some .cmi files
1.0: It is now possible to divide the description of a package into subpackages (but there is still only one META file, but with enhanced syntax). This allows it to describe intra-package dependencies.
Predicates in META files can be negated.
The "error" variable allows you to detect conditions under which the library would not work, and to generate error messages.
It is possible to refer to archive files installed in other packages.
The set of predicates is extended by "package predicates" after the dependency analysis, making conditions expressable that depend on whether other packages are selected.
The "+=" operator in META files adds words to variables rather than setting them.
The "#thread" directive enables multi-threading in toploops and scripts, if possible.
The "#predicates" directive simplifies the addition of predicates.
Queries: The format specifier %D prints the description of the package. -long-format includes the description. Short options -r, -l, -d.
ocamlfind list -describe prints package descriptions.
Support for "ocamlfind ocamldoc". However, the implementation is quite sloppy.
The configuration file is called "findlib.conf" by default, not "ocamlfind.conf".
Removal of "ocamlfind guess".
Support for #use "findlib" and #use "ocamlfind" has been removed. The only remaining way to load findlib is by #use "topfind".
There is no longer a thread-safe version of findlib. The user has to ensure that only one thread uses findlib (which is usually trivial to achieve).
ocamlmktop: Directories are no longer automatically added to the search path. This did not work anyway, and this change forces scripts to always invoke "#require" to load/enable libraries, for better uniformity.
Fixes: num-top works. "ocamlfind ocamlopt -thread" generates a better error message on non-POSIX systems. "ocamlfind query -descendants" takes predicates into account (it did not do that in previous versions of findlib).
0.9: Changes for O'Caml 3.07 (-thread, -vmthread). Includes Zack's toploop printers for bigints.
0.8 - 0.8.1: Renamed a lot of modules to avoid name clashes with O'Caml core modules. Cygwin: Additional option -cygpath for "configure". The man pages have a NAME section. Bugfix in Makefile wizard.
0.7 - 0.7.2: DLLs: There are now two styles of installation: DLLs can be installed in the package directories (like before), or in a shared directory "stublibs". For the first style, there is now an option "ldconf" that determines whether the ld.conf file is to be updated, and if so, which file. The latter style is enabled by simply creating a directory "stublibs" in the site-lib directory. (In the first version the directory was called "libexec". By user request, the name of the DLL directory has been changed to "stublibs".)
"ocamlfind install" preserves now the mtime of the files.
"ocamlfind printconf" is more flexible, and easier to call from scripts.
"ocamlfind browser" calls ocamlbrowser with the right -I options.
"ocamlfind query": -descendants implies now -recursive.
"ocamlfind ocamldep": -native-filter and -bytecode-filter for more exact dependency generation.
There may be now postinstall and postremove scripts.
"ocamlfind pkg/cmd": This syntax can be used to call the program cmd that is installed in the package directory for pkg. Intended to simplify the invocation of programs that are installed in package directories and not in XXX/bin, which may be useful for package- related tools.
Findlib has now a toolbox containing helpful programs besides ocamlfind. For the beginning, there is a Makefile wizard that can be called by "ocamlfind findlib/make_wizard".
#use "topfind" instead of #use "findlib" to avoid name clashes in a certain configuration. #use "findlib" and #use "ocamlfind" are still supported for backward compatibility if the name clash does not occur.
Fix: bytecode threads work again. (The wrong unix library was linked for recent O'Caml versions.)
Many smaller improvements; the docs have been updated.
0.6 - 0.6.2: Minor changes for Ocaml-3.03-alpha (and later for 3.04). New #list directive. New: #use "findlib" loads the findlib directives into every toploop (Ocaml-3.03-alpha).
The file ld.conf is automatically updated when DLLs are installed or removed.
Fix: /tmp/findlib_initf* no longer overflows. The thread library is now always the first linked library.
0.5 - 0.5.4: Findlib has now a configuration file (see documentation under findlib.conf). Much more environment variables. The location of the standard library is now configurable at runtime.
The package search path can now be selected independently of the package installation directory.
New commands: ocamlfind list, ocamlfind printconf, ocamlfind guess (See documentation under ocamlfind)
Optional alternate directory layout: All META files go into a separate directory (see documentation under site-lib).
Findlib works now only for O'Caml 3; support for O'Caml 2 has been dropped. As a consequence, the "configure" script could be simplified; it is no longer necessary to figure out the linker options.
Improved support for camlp4: New directives #camlp4o and #camlp4r for the toploop.
ocamlfind now detects whether two selected packages have equally named toplevel modules, and prints a warning in this case.
There is a downstripped version ocamlfind-mini (see directory "mini"). This is a one-file script that can be easily distributed with any software. ocamlfind-mini has reduced functionality, but it is sufficient to compile and install a library. (But it does not support using a library.)
Support for the Cygwin port of O'Caml.
Installation of packages: The file permissions are preserved when files are installed. However, the umask is applied. The "install" and "remove" subcommands have better diagnostics.
ocamlfind ocamlmktop: Generates now initialization code for the include path. You don't need to call your toploop with -I options any more. Furthermore, this fixes some problems with packages that add printers to the toploop.
New: ocamlfind ocamldep. ocamlfind is now prepared for the new -pp option of ocamldep (upcoming Ocaml 3.03).
Installation of findlib: New PREFIX variable in Makefile to install locally.
Fixes: itest. ocamlfind query -descendants works again.
0.4: Experimental support for camlp4 (see FAQ section in the manual). New environment variable OCAMLFIND_COMMANDS (see ocamlfind(1)).
0.3 - 0.3.1: Necessary updates for O'Caml 3. Bugfix: Findlib did not work for bytecode threads. The reason was that findlib added the directory of the stdlib to the search path. Works now.
Older changes are no longer documented.
</sect1> </readme>