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how to resolve unresolved symbols

Hi all,

I have some questions on how to resolve some undefined symbols. I am not understanding the basic process by which these get defined/resolved, so I hope I can get some info on how this would happen.

I am trying load a .so external to the code base which it was created for use with. These are "plugin" objects that are opened using that code bases plugin manager which internally does its work with dlopen. I have loaded the plugin within the application it was built for use with and everything works. When I run my test harness, which uses the application's plugin manager to open the plugins, I see a dlopen failure to resolve some symbols. Here is the message.

Error opening plugin file: /home/burlen/X/src/plugins/databases/../../lib/ undefined symbol: vtk_zlib_inflateInit_
Invalid plugin: Error opening plugin file for plugin /home/burlen/ext2/visit/visit1.10.0/src/plugins/databases/ The system error message was '/home/burlen/X/src/plugins/databases/../../lib/ undefined symbol: vtk_zlib_inflateInit_'.

I would expect this sort of thing because the loader could not find the right library that the .so referred to in its search path, but when I use ldd to examine the .so I am not seeing anything like that. The library these symbols are actually in is not even listed! Here is what I get.

tycho:~$ldd -r /home/burlen/X/src/lib/ => (0xb7f50000) => /usr/lib/ (0xb7e40000) => /lib/tls/i686/cmov/ (0xb7e1b000) => /lib/ (0xb7e0f000) => /lib/tls/i686/cmov/ (0xb7cc0000)
/lib/ (0xb7f51000)
undefined symbol: _Z10VisItFstatiP6stat64 (/home/burlen/X/src/lib/
undefined symbol: vtk_zlib_inflateInit_ (/home/burlen/X/src/lib/
undefined symbol: vtk_zlib_inflate (/home/burlen/X/src/lib/
undefined symbol: vtk_zlib_inflateEnd (/home/burlen/X/src/lib/
undefined symbol: vtk_zlib_deflateInit_ (/home/burlen/X/src/lib/
undefined symbol: vtk_zlib_deflate (/home/burlen/X/src/lib/
undefined symbol: vtk_zlib_deflateEnd (/home/burlen/X/src/lib/

It works in the original app so I know its just a matter of my not understanding how the loading process works in this case. I am confused about how those undefined symbols would get resolved? How can the loader resolve them with out a path to a specifc .so file? How could the files be linked successfully with those undefined symbols?

Thanks in advance

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