Final answer:
The student is asked to design a simple shell in Linux that supports six specific commands and terminates with a 'quit!' command, involving the use of system programming concepts like 'fork' and 'exec' functions.
Step-by-step explanation:
The question asks about building a minimal shell program in a Linux environment which can only support six commands: clear, pwd, time, date, ls, and which. Additionally, the shell should terminate upon receiving the 'quit!' command. The implementation of such a shell likely involves the use of system programming concepts such as system calls, specifically fork and the exec family of functions, to create new processes and replace the process's memory space with a new program.'fork()' is used to create a new process which is a duplicate of the current process.'exec()' is a group of functions that replaces the current process image with a new process image, thus executing a new program.Command line arguments should be handled properly when executing these Linux commands.These system calls are essential for creating a functional shell that can execute commands within a Linux operating system.
To implement a shell that supports the given commands, you can use the fork and exec system calls. Here's a general outline:Start an infinite loop to repeatedly read user input.Parse the input to identify the command and its arguments.Use fork to create a child process.In the child process, use exec to execute the command with its arguments.In the parent process, use wait to wait for the child process to complete.If the user enters 'quit!', break out of the loop to terminate the shell.When executing the Linux commands, you can use command line options or arguments provided by the user. For example, 'ls -l' or 'date -u'.