Most of the source code ( 71 % ) was written in the C programming language , but many other languages were used , including C++ , Lisp , assembly language , Perl , Python , Fortran , and various shell scripting languages .
Most of the code ( around 71 % ) was written in the C programming language , and many other languages were used , including C++ , assembly language , Perl , Python , Fortran , and various shell scripting languages .