ASIO-README.txt This document contains information to help you compile PortAudio with ASIO support. If you find any omissions or errors in this document please notify Ross Bencina . Building PortAudio with ASIO support ------------------------------------ To build PortAudio with ASIO support you need to compile and link with pa_asio.c, and files from the ASIO SDK (see below), along with the common files from pa_common/ and platform specific files from pa_win/ (for Win32) or pa_mac/ (for Macintosh). If you are compiling with a non-Microsoft compiler on windows, also compile and link with iasiothiscallresolver.cpp (see below for an explanation). For some platforms (MingW, possibly Mac), you may simply be able to type: ./configure --with-host_os=mingw --with-winapi=asio [--with-asiodir=/usr/local/asiosdk2] make ./configure --with-host_os=darwin --with-winapi=asio [--with-asiodir=/usr/local/asiosdk2] make and life will be good. Obtaining the ASIO SDK ---------------------- In order to build PortAudio with ASIO support, you need to download the ASIO SDK (version 2.0) from Steinberg. Steinberg makes the ASIO SDK available to anyone free of charge, however they do not permit its source code to be distributed. NOTE: In some cases the ASIO SDK may require patching, see below for further details. http://www.steinberg.net/en/ps/support/3rdparty/asio_sdk/ If the above link is broken search Google for: "download steinberg ASIO SDK" Building the ASIO SDK on Macintosh ---------------------------------- To build the ASIO SDK on Macintosh you need to compile and link with the following files from the ASIO SDK: host/asiodrivers.cpp host/mac/asioshlib.cpp host/mac/codefragements.cpp Building the ASIO SDK on Windows -------------------------------- To build the ASIO SDK on Windows you need to compile and link with the following files from the ASIO SDK: asio_sdk\common\asio.cpp asio_sdk\host\asiodrivers.cpp asio_sdk\host\pc\asiolist.cpp You may also need to adjust your include paths to support inclusion of header files from the above directories. The ASIO SDK depends on the following COM API functions: CoInitialize, CoUninitialize, CoCreateInstance, CLSIDFromString For compilation with MinGW you will need to link with -lole32, for Borland link with Import32.lib. Non-Microsoft (MSVC) Compilers on Windows including Borland and GCC ------------------------------------------------------------------- Steinberg did not specify a calling convention in the IASIO interface definition. This causes the Microsoft compiler to use the proprietary thiscall convention which is not compatible with other compilers, such as compilers from Borland (BCC and C++Builder) and GNU (gcc). Steinberg's ASIO SDK will compile but crash on initialization if compiled with a non-Microsoft compiler on Windows. PortAudio solves this problem using the iasiothiscallresolver library which is included in the distribution. When building ASIO support for non-Microsoft compilers, be sure to compile and link with iasiothiscallresolver.cpp. Note that iasiothiscallresolver includes conditional directives which cause it to have no effect if it is compiled with a Microsoft compiler, or on the Macintosh. If you use configure and make (see above), this should be handled automatically for you. For further information about the IASIO thiscall problem see this page: http://www.audiomulch.com/~rossb/code/calliasio Macintosh ASIO SDK Bug Patch ---------------------------- There is a bug in the ASIO SDK that causes the Macintosh version to often fail during initialization. Below is a patch that you can apply. In codefragments.cpp replace getFrontProcessDirectory function with the following one (GetFrontProcess replaced by GetCurrentProcess). bool CodeFragments::getFrontProcessDirectory(void *specs) { FSSpec *fss = (FSSpec *)specs; ProcessInfoRec pif; ProcessSerialNumber psn; memset(&psn,0,(long)sizeof(ProcessSerialNumber)); // if(GetFrontProcess(&psn) == noErr) // wrong !!! if(GetCurrentProcess(&psn) == noErr) // correct !!! { pif.processName = 0; pif.processAppSpec = fss; pif.processInfoLength = sizeof(ProcessInfoRec); if(GetProcessInformation(&psn, &pif) == noErr) return true; } return false; } ---