ldd (List Dynamic Dependencies) is a *nix utility that prints the shared libraries required by each program or shared library specified on the command line. It was developed by Roland McGrath and Ulrich Drepper. ldd is a shell script that executes the program given as argument, and shouldn't be used with untrusted binaries. If some shared library is missing for any program, that program won't come up.
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Ldd (Unix) Wikipedia(Text) CC BY-SA