In the list below, commands that can accept more than one file name, or a filename including wildcards (* and ?), are said to accept a filespec (file specification) parameter. Copies of these utility command programs had to be on an accessible disk, either on the current drive or on the command path set in the command interpreter. Such utility programs would be stored on disk and loaded just like regular application programs but were distributed with the operating system.
If no match is found, an error message is printed, and the command prompt is refreshed.Įxternal commands were too large to keep in the command processor, or were less frequently used. When the user types a line of text at the operating system command prompt, COMMAND.COM will parse the line and attempt to match a command name to a built-in command or to the name of an executable program file or batch file on disk. Some commands are internal-built into COMMAND.COM others are external commands stored on disk. When an application exits, if the transient portion of the command interpreter in memory was overwritten, DOS will reload it from disk. The command interpreter for DOS runs when no application programs are running.
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