I've created a GitHub fork of ChucK, the "strongly-timed, concurrent, and on-the-fly audio programming language." In my fork I've started to add missing features like string methods, and hope to add many more such as raw file I/O and perhaps some form of MIDI file I/O.
So far, I've added string.ch which is a getter and setter for string characters (really one-character length substrings) and string.substr. This allowed me to write a function in ChucK that converts strings like "c#4" to MIDI note numbers.
It looks like ChucK's code was last updated in 2006, so I don't feel to bad about forking it.
Update: I just read in the chuck email list archive that the team is planning to start active development again, and they will be adding file I/O. If they get it done before I do, that would be very nice.