Creating a Child Process
The first task is to modify the main() function in the code shown above so that a child process is forked and executes the command specified by the user. This will require parsing what the user has entered into separate tokens and storing the tokens in an array of character strings (args in above code). For example, if the user enters the command ps -ael at the CS30> prompt, the values stored in the args array are:
args[0] = "ps"
args[1] = "-ael"
args[2] = NULL
This args array will be passed to the execvp() function, which has the following prototype:
execvp(char *command, char *params[]);
Here, command represents the command to be performed and params stores the parameters to this command. For this project, the execvp() function should be invoked as
execvp(args[0], args)
Be sure to check whether the user included an & to determine whether or not the parent process is to wait for the child to exit.