Thread: difference in the content of Dll and Lib

  1. 07-07-2008 #1
    Alexpo
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    difference in the content of Dll and Lib

    Hi,

    There are some questions regarding dll and library .

    I know,static library files are linked statically by linker at start up.On the other hand dll was used to link the required functions(code)at run time.

    But, to link a dll why do we need an .lib file also.(As for a dll we have (1) an .h file - to compile against and (2)a .lib file to link agianst and (3)a .dll file itself.)?

    What are the difference in the contents of .dll and .lib??

    Why can't we have a .dll inspite of .lib and .dll???

    Thanks and Regards,
  2. 07-07-2008 #2
    matsp
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    A .lib file contains functions that are linked in at link time (that is, when you are combining the results of the compilation into an executable file).

    For DLL's, in the way it works with Windows, the lib for a DLL contains "stub functions", which essentially is a jump to the relevant location in the DLL. There is also a reference in the .lib file that makes it possible to build the "DLL import table", which tells the loader (the part of the OS that loads executable files [including DLL's]) what DLL's are needed, and which functions in the DLL that are being used (and a reference to where in the original file that particular function is used - that is, where the stub is).

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