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The nm command ships with a number of later versions of Unix and similar operating systems. nm is used to examine binary files (including libraries, compiled object modules, shared-object files, and standalone executables) and to display the contents of those files, or meta information stored in them, specifically the symbol table. The output from nm distinguishes between various symbol types, for example it differentiates between a function which is supplied by an object module and a function which is required by it. nm is used as an aid for debugging, to help resolve problems arising from name conflicts and C++ name mangling, and to validate other parts of the toolchain.