MCQ IN COMPUTER SCIENCE & ENGINEERING

Detailed explanation-1: -External commands are predefined commands for end users. They are operating-system independent and are protected by authorizations, so that normal end users can schedule only those commands that the system administrator permits them to.

Detailed explanation-2: -Internal commands are commands that are already loaded in the system. They can be executed any time and are independent. On the other hand, external commands are loaded when the user requests for them. Internal commands don’t require a separate process to execute them. External commands will have an individual process.

Detailed explanation-3: -An internal command is embedded into the COMMAND.COM file, and an external command is not and requires a separate file to operate. For example, if your computer does not have the fdisk.exe file and you try using the fdisk command, you will receive a “Bad command or file name” error message.

Detailed explanation-4: -Some commands that you type are internal, which means they are built into the shell, and it’s the shell that performs the action. For example, the cd command is built-in. The ls command, on the other hand, is an external program stored in the file /bin/ls.