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In the root directory, we can find several 'lib' subfolder, for example, '/lib', 'lib32', lib64', '/usr/lib', '/usr/lib32', '/usr/local/lib'. Then what are their difference ?
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In addition to shared and static libraries which are the lib-directories main purpose, you may also find some hierarchies (with their own lib, bin, include and so on) for some larger packages under them.