The command csound is a basic frontend to the system that can be used to generate a sound output from an orchestra file and a score file (or a unified csd file). It is designed to be called from a terminal or DOS window. In addition to it, there are other front-ends, which might be simpler to use. The score file can be in one of many different formats, according to user preference. Translation, sorting, and formatting into orchestra-readable numeric text is handled by various preprocessors; all or part of the score is then sent on to the orchestra. Orchestra performance is influenced by command flags, which set the level of displays and console reports, specify I/0 filenames and sample formats, and declare the nature of real-time sensing and control.
There are five places where options for Csound performance may be set. They are processed in the following order:
Csound's own defaults
File defined by the CSOUNDRC environment variable, or .csoundrc file in the HOME directory
A .csoundrc file in the current directory
<CsOptions> tag in a .csd file
Passed on the Csound command line
The later options in the list will override any earlier ones. As of version 5.01 of Csound, sample and control rate override flags (-r and -k) specified anywhere override sr, kr, and ksmps defined in the orchestra header.