How would you list the available functions etc contained within a compiled library?

Question

How do I determine whether a function exists within a library, or list out the functions in a compiled library?

Answer 1

You can use the nm command to list the symbols in static libraries.

nm -g -C <libMylib.a>

Answer 2

use this command:

objdump -t "your-library"

It will print more than you want - not just function names, but the entire symbol table. Check the various attributes of the symbols you get, and you will be able to sort out the functions from variables and stuff.

Answer 3

Under Linux/Unix you can use objdump -T to list the exported symbols contained in a given object. Under Windows there's dumpbin (IIRC dumpbin /exports). Note that C++ function names are mangled in order to allow overloads.

EDIT: after seeing codelogic's anwser I remembered that objdump also understands -C to perform de-mangling.

Answer 4

For ELF binaries, you can use readelf:

readelf -sW a.out | awk '$4 == "FUNC"' | c++filt

-s: list symbols -W: don't cut too long names

The awk command will then filter out all functions, and c++filt will unmangle them. That means it will convert them from an internal naming scheme so they are displayed in human readable form. It outputs names similar to this (taken from boost.filesystem lib):

285: 0000bef0    91 FUNC    WEAK   DEFAULT   11 boost::exception::~exception()

Without c++filt, the name is displayed as _ZN5boost9exceptionD0Ev

Answer 5

For Microsoft tools, "link /dump /symbols <filename>" will give you the gory details. There are probably other ways (or options) to give an easier to read listing.