SoX (short for Sound eXchange) is a very useful multi-purpose tool for manipulating sound files. It can convert between many different file formants, and can also add various effects to the signal. It can be downloaded here.
After downloading the source code (version 14.3.0) and succesfully compiling it on Ubuntu 9.04, I received the following error when trying to start up SoX:
$ sox
sox: error while loading shared libraries: libsox.so.1: cannot open shared object file: No such file or directory
After a little poking around, I see that the file libsox.so.1 was installed to /usr/local/lib when SoX was installed. Also, /usr/local/lib is included in the file /etc/ld.so.conf (the system file which contains a list of shared libraries). However, to link these newly installed libraries and make them accessible, I needed to run the following command:
$ sudo ldconfig
After running that, SoX worked just fine.
