C++, Ubuntu, codeblocks, GCC, LCM version 0.9.0: "undefined reference to lcm_create" in lcm-cpp-impl.hpp

[Chad Schaffer]

it's also complaining about "lcm_destroy" and "lcm_publish" in the
same file.

I thought this might have something to do with the code I was writing
so I tried compiling the tutorial example and got the same error so I
suspect it's my install...

Does anyone have an idea's about this?

[Albert Huang]

Hi Chad,

It sounds like you're not linking your program correctly. Are you
using -llcm or `pkg-config --libs lcm` ?

Albert

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[Chad Schaffer]

I'm a novice to programming, and am not sure where these commands should be used.  I have used neither "-llcm" nor "pkg-config --libs lcm".  Is this something done during install?  at what point should I used which command?

[Albert Huang]

Hi Chad,

I would suggest going through some introductory material on compiling
and linking. It's definitely something you'll want to be very
familiar with as you learn more about programming. Based on a cursory
google search, this page seems like it might have some useful
information: http://www.yolinux.com/TUTORIALS/LibraryArchives-StaticAndDynamic.html

Albert

[Chad Schaffer]

thank you so much!

[atefe moosavi]

dear Chad Schaffer
I am using lcm and have a same problem while compiling the lcm example! could you tell me what is the solution? could you compile it?
thanks

[Andrea Nisticò]

I have the exact problem, how did you solve it? Thanks in advance

[Chad Schaffer]

I was just bouncing around and found this thread from so long ago...

I must have missed that people needed help. Sorry!

You need to add  `pkg-config --libs lcm` to your g++ command to properly link lcm files

Be it in command line or makefile

for instance:

g++ main.cpp  `pkg-config --libs lcm` -o test_exe

Hope this helps someone down the line.