Menu
What is the difference between a DLL and a LIB file? What is inside a DLL file and what is inside a LIB file? Are both DLL and LIB files necessary to create an executable?
833
When you use run-time dynamic linking, you do not need an import library file. If the initial startup performance of the application is important, you should use run-time dynamic linking. In load-time dynamic linking, the exported DLL functions are like local functions.
LIB (lib.exe) creates standard libraries, import libraries, and export files you can use with LINK when building a program.
Dynamic linking has the following advantages: Saves memory and reduces swapping. Many processes can use a single DLL simultaneously, sharing a single copy of the DLL in memory. In contrast, Windows must load a copy of the library code into memory for each application that is built with a static link library.
A DLL file is the final build product, that's what you install on your customer's machine. It is very similar to an EXE file, same structure, but can be loaded on demand into another program.
A LIB file is used to build your program, it only exists on your build machine and you don't ship it. There are two kinds. A static link library is a bag of .obj files, collected into a single file. The linker picks any chunks of code from the file when it needs to resolve an external identifier.
But more relevant to DLLs, a LIB file can also be an import library. It is then a simple small file that includes the name of the DLL and a list of all the functions exported by the DLL. You'll need to provide it to the linker when you build a program that uses the DLL so it knows that an external identifier is actually a function exported by the DLL. The linker uses the import library to add entries to the import table for the EXE. Which is then in turn used by Windows at runtime to figure out what DLLs need to be loaded to run the program.
148
If you love us? You can donate to us via Paypal or buy me a coffee so we can maintain and grow! Thank you!
Donate Us With
