DSO missing from command line

Question

I am trying to compile a C++ program like this:

$ g++ -o Sniffer_Train main.cpp Sniffer_train.cpp Sniffer_train.h -lmysqlclient -lpcap

However I get the following error:

/usr/bin/ld: /tmp/cct6xeXD.o: undefined reference to symbol
'pthread_join@@GLIBC_2.4' //lib/arm-linux-gnueabihf/libpthread.so.0:
error adding symbols: DSO missing from command line

collect2: error: ld returned 1 exit status

I have no idea what this error means. Any help will be greatly appreciated.

Solution

DSO here means Dynamic Shared Object; since the error message says it's missing from the command line, I guess you have to add it to the command line.

That is, try adding -lpthread to your command line.

Comments

[Alex]

Thanks, I had a similar problem with some other project and was able to solve it this way. I just want to add that now that I looked closer I can see that the error is actually very unambigious on what the problem is. I mean, it does say that pthread_join is undefined and that it belongs to libpthread.so. But like srai I had no idea what the error meant until I came here. :-)

[acgtyrant]

Does the error show that the ld know the needed DSO is //lib/arm-linux-gnueabihf/libpthread.so.0?