The OS/2 API Project (also known as The OS/2 API Documentation Project) is an effort that aims to document all the OS/2 available APIs under an non-restrictive license that can allow derivative works. 
For contributors, please review the Introduction to the OS/2 API Documentation.
OS/2 Warp APIs
This are the APIs included on the IBM's OS/2 Warp product. 
  | Control ProgramLanguagesRuntime Libraries
Language Support
 NetworkEnvironment Calls | KernelPresentation ManagerSystem Object Model (SOM) | DriversOEM HelperASPI RouterUSB stack driver (usbd)
 MultimediaOthers | 
Third Parties OS/2 Based APIs
This table lists the third party APIs based on the component level they run. 
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KernelControl ProgramNetworkPresentation ManagerSystem Object Model (SOM)DriversMMOS2REXXVXREXXOthers | 
OS/2 Ported APIs
These are APIs ported from other platforms to OS/2-eCS-ArcaOS. The functions documentation of the APIs are only linked to their respective sites. 
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Control ProgramDatabaseDB4 - The Berkeley DB Database Library (klibc)sqlite (klibc)
 Filesfile-libs - Fine Free File Command (klibc)
 GraphicsI/Olibaio (klibc)libusb (klibc) [1]
 Multimediaffmpeg (klibc)libkai - K Audio Interface Library (klibc)libvpx - VP8 Video CODEC (klibc)libdvdnav (klibc)poppler - PDF rendering library (klibc)x264
 Networknss - Network Security Services (klibc)libcurl (klibc)nspr - Netscape Portable Runtime (klibc)
 PrintProgramming Languages LibLIBClibssp - GNU Stack Protector Shared Library (klibc)mmap (klibc)perl (klibc)python (klibc)pthread (klibc)urpo (klibc)
 Regional / Languagesgettext (klibc)icu - libicu - International Components for Unicode (klibc)libiconv
 Securitylibgpg-error (klibc)libgcrypt (klibc)openssl (klibc)
 Utilitylibvnc (klibc)ncurses library (klibc)rpm (klibc)
 XMLCPresentation ManagerGraphicsFontsfontconfig  (klibc)pango (klibc)
 KLIBCThis are the libraries/runtimes that does not depends directly on CPI or PM. 
 Data Compressionliblzma - LZMA Libraryzlib
 Fonts / TextGraphicslcms2 - Little CMSlibjpeg-turbolibjpg - Independent JPEG GroupLibTiff - [2]libpngpixman
 Interfacelibidl - IDL Parsing Library
 Mathgmp - The GNU Multiple Precision Arithmetic Librarylibmpc - GNU MPCmpfr - The GNU MPFR Library
 MultimediaPrintProgramming LanguagesGCClibstdc++ - GNU Standard C++ Librarypcre - Pearl-compatible Regular Expression Library
 UtilitiesXML | 
| ContributorsThe contributors of the OS/2 API Project: 
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