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Write the concept of linker in embedded system.

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In ES a linker or link editor is a program that takes one or more objects generated by a compiler and combines them into a single executable program.

 Static linking:
•Static linking is the process of copying all library modules used in the program into the final executable image.
•Statically linked program takes constant load time every time it is loaded into the memory for execution.
•Static linking is performed by programs called linkers as the last step in compiling a program.

 Dynamic linking:
•In dynamic linking the names of the external libraries (shared libraries) are placed in the final executable file while the actual linking takes place at run time when both executable file and libraries are placed in the memory.
•In dynamic linking load time might be reduced if the shared library code is already present in memory.
•Dynamic linking is performed at run time by the operating system.

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