Shell

In computing, a shell is a user interface for access to an operating system's services. In general, operating system shells use either a command-line interface (CLI) or graphical user interface (GUI), depending on a computer's role and particular operation. It is named a shell because it is a layer around the operating system kernel.

OS/2 CONFIG.SYS statements

 * PROTSHELL - CONFIG.SYS command to define protected mode shell
 * Example: PROTSHELL=C:\OS2\PMSHELL.EXE


 * SHELL - CONFIG.SYS command to define DOS command interpreter
 * Example: SHELL=C:\OS2\MDOS\COMMAND.COM C:\OS2\MDOS /P


 * OS2_SHELL - Environment variable
 * Example: SET OS2_SHELL=C:\OS2\CMD.EXE

See also: UNIX Shell