> Do the executables know; as in could I (or someone that knows how to program)
> be able to write a program that would query the programs in question to find
> out which library they are using?

'ldd' will do what you ask.

e.g.:

237 [sun-lamp] trees % ldd /usr/bin/groff 
/usr/bin/groff:
        -lm.0 => /usr/lib/libm.so.0.0 (0x10024000)
        -lgnumalloc.0 => /usr/lib/libgnumalloc.so.0.0 (0x10031000)
        -lc.9 => /usr/lib/libc.so.9.0 (0x10035000)


cgd

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