Sometimes when you try to launch an application on Linux, typically one you have built yourself, you might get an error like this:
./myapp: error while loading shared libraries: libpq.so.5: cannot open shared object file: No such file or directory
When this happens, it is up to you to figure out what the problem is. Fortunately, you have a tool called ldd to help.
# using which to get the full path to the executable ldd $(which sh) linux-vdso.so.1 => (0x00007fff44fff000) libtinfo.so.5 => /lib64/libtinfo.so.5 ...
If any of the shared (dynamic) libraries are not found, you will have to locate them and add them to your LD_LIBRARY_PATH environment variable. something like the following should do the trick: