int parseline(const char *cmdline, char **argv);       
   

This function extracts the command line arguments from the string cmdline and stores them in the string array argv that you must declare and pass to parseline. (How big should the array be?)

Parseline adds one more entry - a NULL pointer that is needed by the execvp function.

You should not change this function.

Note: eval should handle the case that the user simply hits the enter key without typing a command by returning to main.

In this case, what does parseline put in argv?