Part $1$: The Simple Shell

Your shell executable should be named sish. Your shell's source code should be in

sish.c$,$

The shell should run continuously and display a prompt when waiting for input. The

prompt should be EXACTLY sish$>.$ Note the space after greater than sign. Example with

a command:

sish$>1s-1$

Your shell should read a line from stdin one at a time. This line should be parsed out

into a command and all its arguments. In other words, tokenize it$.$

You may assume that the only supported delimiter is the whitespace character

$($ASCII character number $32).$

You do not need to handle "special" characters. Do not worry about handling

quotation marks, backslashes, and tab characters. This means your shell will be

unable to support arguments with spaces in them. For example, your shell will not

support file paths with spaces in them.

You may set a reasonable maximum on the number of command line arguments,

but your shell should handle input lines of any length.

After parsing the command, your shell should execute it$.$ A command can either be a

reference to an executable OR a built$-$in shell command $($see Part $2).$ For Part $1,$ just focus

on running executables, and not on built$-$in commands.

Executing commands that are not shell built$-$ins and are just the executable name

$($and not a full path to the executable$)$ is done by invoking fork $()$ and then

invoking execvp $().$

You may NOT use the system $()$ function, as it just invokes the $/$bin$/$sh shell to

do all the work.