Introduction to tcsh Download location (HTTP): Download location (FTP): Version used: &tcsh-version; Package size: &tcsh-size; Estimated Disk space required: &tcsh-buildsize; Estimated build time: &tcsh-time; The tcsh package contains "an enhanced but completely compatible version of the Berkeley UNIX C shell (csh)". This is useful as an alternative shell for those who prefer C syntax to that of the bash shell, and also because some programs require the C shell in order to install.