A static library gets compiled into the client. A .lib is used at compile time and the contents of the library become part of the consuming executable.
A dynamic library is loaded at runtime and not compiled into the client executable. Dynamic libraries are more flexible as multiple client executables can load a DLL and utilize its functionality. This also keeps the overall size and maintainability of your client code to a minimum.
You should think carefully about changes over time, versioning, stability, compatibility, etc.
If there are two apps that use the shared code, do you want to force those apps to change together, in case they need to be compatible with each other? Then use the dll. All the exe's will be using the same code.
Or do you want to isolate them from each other, so that you can change one and be confident you haven't broken the other. Then use the static lib.
DLL hell is when you probably SHOULD HAVE used a static lib, but you used a dll instead, and not all the exes are comaptible with it.
A lib is a unit of code that is bundled within your application executable.
A dll is a standalone unit of executable code. It is loaded in the process only when a call is made into that code. A dll can be used by multiple applications and loaded in multiple processes, while still having only one copy of the code on the hard drive.
Dll pros: can be used to reuse/share code between several products; load in the process memory on demand and can be unloaded when not needed; can be upgraded independently of the rest of the program.
Dll cons: perf impact of the dll loading and code rebasing; versioning problems ("dll hell")
Lib pros: no perf impact as code is always loaded in the process and is not rebased; no versioning problems.
Lib cons: executable/process "bloat" - all the code is in your executable and is loaded upon process start; no reuse/sharing - each product has its own copy of the code.
Static libraries increase the size of the code in your binary. They're always loaded and whatever version of the code you compiled with is the version of the code that will run.
Dynamic libraries are stored and versioned separately. It's possible for a version of the dynamic library to be loaded that wasn't the original one that shipped with your code if the update is considered binary compatible with the original version.
Additionally dynamic libraries aren't necessarily loaded -- they're usually loaded when first called -- and can be shared among components that use the same library (multiple data loads, one code load).
Dynamic libraries were considered to be the better approach most of the time, but originally they had a major flaw (google DLL hell), which has all but been eliminated by more recent Windows OSes (Windows XP in particular).
A dynamic library is loaded at runtime and not compiled into the client executable. Dynamic libraries are more flexible as multiple client executables can load a DLL and utilize its functionality. This also keeps the overall size and maintainability of your client code to a minimum.
You should think carefully about changes over time, versioning, stability, compatibility, etc.
If there are two apps that use the shared code, do you want to force those apps to change together, in case they need to be compatible with each other? Then use the dll. All the exe's will be using the same code.
Or do you want to isolate them from each other, so that you can change one and be confident you haven't broken the other. Then use the static lib.
DLL hell is when you probably SHOULD HAVE used a static lib, but you used a dll instead, and not all the exes are comaptible with it.
A lib is a unit of code that is bundled within your application executable.
A dll is a standalone unit of executable code. It is loaded in the process only when a call is made into that code. A dll can be used by multiple applications and loaded in multiple processes, while still having only one copy of the code on the hard drive.
Dll pros: can be used to reuse/share code between several products; load in the process memory on demand and can be unloaded when not needed; can be upgraded independently of the rest of the program.
Dll cons: perf impact of the dll loading and code rebasing; versioning problems ("dll hell")
Lib pros: no perf impact as code is always loaded in the process and is not rebased; no versioning problems.
Lib cons: executable/process "bloat" - all the code is in your executable and is loaded upon process start; no reuse/sharing - each product has its own copy of the code.
Static libraries increase the size of the code in your binary. They're always loaded and whatever version of the code you compiled with is the version of the code that will run.
Dynamic libraries are stored and versioned separately. It's possible for a version of the dynamic library to be loaded that wasn't the original one that shipped with your code if the update is considered binary compatible with the original version.
Additionally dynamic libraries aren't necessarily loaded -- they're usually loaded when first called -- and can be shared among components that use the same library (multiple data loads, one code load).
Dynamic libraries were considered to be the better approach most of the time, but originally they had a major flaw (google DLL hell), which has all but been eliminated by more recent Windows OSes (Windows XP in particular).
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