DOCUMENT:Q154753 28-MAY-2002 [visualc] TITLE :INFO: What Are the C/C++ Libraries My Program Would Link With? PRODUCT :Microsoft C Compiler PROD/VER::4.2,5.0 OPER/SYS: KEYWORDS:kbCompiler kbGenInfo kbLangCPP kbVC420 kbVC500 kbVC600 kbArtTypeINF ====================================================================== ------------------------------------------------------------------------------- The information in this article applies to: - Microsoft Visual C++, 32-bit Enterprise Edition, versions 4.2, 5.0 - Microsoft Visual C++, 32-bit Professional Edition, versions 4.2, 5.0 - Microsoft Visual C++.NET (2002) ------------------------------------------------------------------------------- SUMMARY ======= This article describes the default libraries LIBC[D].LIB, LIBCMT[D].LIB, LIBCI[D].LIB, LIBCIMT[D].LIB, LIBCP[D].LIB, LIBCPMT[D].LIB, MSVCRT[D].LIB, MSVCIRT[D].LIB, and MSVCPRT[D].LIB that a program will link with when built using Visual C++. MORE INFORMATION ================ When you build a release (or debug) version of your project in Visual C++, one of the basic C Runtime libraries (LIBC[D].LIB, LIBCMT[D].LIB, and MSVCRT[D].LIB) is linked by default, depending on the compiler option you choose (single-threaded , multithreaded , or multithreaded DLL). A library from the Standard C++ Library or one from the old iostream library may also be linked depending on the headers you use in your code. For example, consider the following cases: Case 1: Sample program test1.cpp -------------------------------- // test1.cpp void main() { } - If you build test.cpp using the /ML (or /MLd, for a debug build) compiler option, your program will link with LIBC.LIB (or LIBCD.LIB, for debug build), in addition to other libraries. - If you build test.cpp using the /MT (or /MTd, for a debug build) compiler option, your program will link with LIBCMT.LIB (or LIBCMTD.LIB, for debug build), in addition to other libraries. - If you build test.cpp using the /MD (or /MDd, for a debug build)compiler option, your program will link with MSVCRT.LIB (or MSVCRTD.LIB, for debug build), in addition to other libraries. In this case, your program will be dependent on MSVCRT.DLL (or MSVCRTD.DLL for debug build). Case 2: Sample program test2.cpp -------------------------------- // test2.cpp #include void main() { } - If you build test.cpp using the /ML (or /MLd, for a debug build) compiler option, your program will link with LIBC.LIB (or LIBCD.LIB, for debug build) and LIBCP.LIB (or LIBCPD.LIB, for debug build), in addition to other libraries. - If you build test.cpp using the /MT (or /MTd, for a debug build) compiler option, your program will link with LIBCMT.LIB (or LIBCMTD.LIB, for debug build) and LIBCPMT.LIB (or LIBCPMTD.LIB, for debug build), in addition to other libraries. - If you build test.cpp using the /MD (or /MDd, for a debug build) compiler option, your program will link with MSVCRT.LIB (or MSVCRTD.LIB, for debug build) and MSVCPRT.LIB (or MSVCPRTD.LIB, for debug build), in addition to other libraries. For Visual C++ 6.0, your program will be dependent on MSVCRT.DLL and MSVCP60.DLL (or MSVCRTD.DLL and MSVCP60D.DLL for debug build). For Visual C++ 5.0, your program will be dependent on MSVCRT.DLL and MSVCP50.DLL (or MSVCRTD.DLL and MSVCP50D.DLL for debug build). For Visual C++ 4.2, your program will be dependent on MSVCRT.DLL (or MSVCRTD.DLL for debug build) and MSVCPRT.LIB (or MSVCPRTD.LIB, for debug build). Case 3: Sample program test3.cpp -------------------------------- // test.cpp #include void main() { } - If you build test.cpp using the /ML (or /MLd, for a debug build) compiler option, your program will link with LIBC.LIB (or LIBCD.LIB, for debug build) and LIBCI.LIB (or LIBCID.LIB, for debug build), in addition to other libraries. - If you build test.cpp using the /MT (or /MTd, for a debug build) compiler option, your program will link with LIBCMT.LIB (or LIBCMTD.LIB, for debug build) and LIBCIMT.LIB (or LIBCIMTD.LIB, for debug build), in addition to other libraries. - If you build test.cpp using the /MD (or /MDd, for a debug build) compiler option, your program will link with MSVCRT.LIB (or MSVCRTD.LIB, for debug build) and MSVCIRT.LIB (or MSVCIRTD.LIB, for debug build) in addition to other libraries. In this case, your program will be dependent on MSVCRT.DLL (or MSVCRTD.DLL for debug build) and MSVCIRT.DLL (or MSVCIRTD.DLL for debug build). Headers determine whether the Standard C++ libraries, old iostream libraries, or neither will be linked. Compiler options (/ML[d], /MT[d], /MD[d]) determine which version of the libraries single-threaded, multithreaded, or multithreaded DLL is to be linked by default. NOTE: It may seem that headers without the ".h" extension are Standard C++ headers and that headers with the ".h" extension are C Runtime headers or old iostream headers. This is not true. As explained below, the files and determine the libraries your application will link with. Actually, there are two header files, and , that contain #pragmas. The #pragmas force either the old iostream library or the Standard C++ library to be linked in by default. The header file contains #pragma statements, which force the old iostream library to be linked in. All old iostream headers include . So, if you include any old iostream header in your application, the old iostream library will be linked by default. The following table lists all the header files that include . Old iostream Headers -------------------- FSTREAM.H IOMANIP.H IOS.H IOSTREAM.H ISTREAM.H OSTREAM.H STDIOSTR.H STREAMB.H STRSTREA.H The header file contains #pragma statements that force the Standard C++ Library to be linked in. All Standard C++ Headers include . So if you include any Standard C++ header in your application, the Standard C++ library will be linked by default. The following table lists all the header files that include . Standard C++ Headers ------------------------------------------------------ ALGORITHM BITSET COMPLEX DEQUE FSTREAM FUNCTIONAL IOMANIP IOS IOSFWD IOSTREAM ISTREAM ITERATOR LIMITS LIST LOCALE MAP MEMORY NUMERIC OSTREAM QUEUE SET SSTREAM STACK STDEXCEPT STREAMBUF STRING STRSTREAM TYPEINFO UTILITY VALARRAY VECTOR XIOSBASE XLOCALE XLOCINFO XLOCMON XLOCNUM XLOCTIME XMEMORY XSTRING XTREE XUTILITY YMATH.H You cannot mix calls to the old iostream library and the new Standard C++ Library in Visual C++ 4.2. Summary Table ------------------------------------------------------------------ | Compile Old New IOStream Libraries | | Option IOStream or STL Linked With | |================================================================| | /ML No No LIBC.LIB | |----------------------------------------------------------------| | /MLd No No LIBCD.LIB | |----------------------------------------------------------------| | /MT No No LIBCMT.LIB | |----------------------------------------------------------------| | /MTd No No LIBCMTD.LIB | |----------------------------------------------------------------| | /MD No No MSVCRT.LIB | |----------------------------------------------------------------| | /MDd No No MSVCRTD.LIB | |----------------------------------------------------------------| | /ML No Yes LIBC.LIB, LIBCP.LIB | |----------------------------------------------------------------| | /MLd No Yes LIBCD.LIB, LIBCPD.LIB | |----------------------------------------------------------------| | /MT No Yes LIBCMT.LIB, LIBCPMT.LIB | |----------------------------------------------------------------| | /MTd No Yes LIBCMTD.LIB, LIBCPMTD.LIB | |----------------------------------------------------------------| | /MD No Yes MSVCRT.LIB, MSVCPRT.LIB | |----------------------------------------------------------------| | /MDd No Yes MSVCRTD.LIB, MSVCPRTD.LIB | |----------------------------------------------------------------| | /ML Yes No LIBC.LIB, LIBCI.LIB | |----------------------------------------------------------------| | /MLd Yes No LIBCD.LIB, LIBCID.LIB | |----------------------------------------------------------------| | /MT Yes No LIBCMT.LIB, LIBCIMT.LIB | |----------------------------------------------------------------| | /MTd Yes No LIBCMTD.LIB, LIBCIMTD.LIB | |----------------------------------------------------------------| | /MD Yes No MSVCRT.LIB, MSVCIRT.LIB | |----------------------------------------------------------------| | /MDd Yes No MSVCRTD.LIB, MSVCIRTD.LIB | ------------------------------------------------------------------ Summary Table for CRT DLLs Used --------------------------------------------------- | Import Library DLLs Used DLLs Used | | Linked With (VC 5.0|6.0) (VC 4.2) | |=================================================| | MSVCRT.LIB MSVCRT.DLL MSVCRT.DLL | |-------------------------------------------------| | MSVCRTD.LIB MSVCRTD.DLL MSVCRTD.DLL | |-------------------------------------------------| | MSVCPRT.LIB MSVCP5(5|6)0.DLL | |-------------------------------------------------| | MSVCPRTD.LIB MSVCP5(5|6)0D.DLL | |-------------------------------------------------| | MSVCIRT.LIB MSVCIRT.DLL MSVCIRT.DLL | |-------------------------------------------------| | MSVCIRTD.LIB MSVCIRTD.DLL MSVCIRTD.DLL | --------------------------------------------------- REFERENCES ========== For additional information, click the article number below to view the article in the Microsoft Knowledge Base: Q154419 INFO: Standard C++ Library Frequently Asked Questions Additional query words: MSVCRT.DLL MSVCIRT.DLL MSVCPRT.LIB LIBCI.LIB LIBCIMT.LIB LIBCP.LIB LIBCPMT.LIB ====================================================================== Keywords : kbCompiler kbGenInfo kbLangCPP kbVC420 kbVC500 kbVC600 kbArtTypeINF Technology : kbVCsearch kbAudDeveloper kbVC420 kbVC500 kbVC32bitSearch kbVCNET kbVC500Search Version : :4.2,5.0 Issue type : kbinfo ============================================================================= THE INFORMATION PROVIDED IN THE MICROSOFT KNOWLEDGE BASE IS PROVIDED "AS IS" WITHOUT WARRANTY OF ANY KIND. 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