Write a program $($myshell$1.$c$)$ to do the following task in a loop

$(1)$ get a command from standard input, into a variable

$(2)$ if the command is "exit"

then exit the program $($to be terminated$)$

else if the command is "listall"

then you replace the input by $"$Is $-$la$"$

else if the command is "showme"

then replace the command by $"$w $|$ grep xyz$"$ where xyz is the first $3$ characters of your netid

for example, w $|$ grep rkm $($for netid$=$rkm$010300)$

else run the command via system call

call a system call to run the input command, e$.$g$.,$ system$("$Is $-$l$")$;

$(3)$ repeat the loop $($that is$,$ back to step $(1)).$

compile the program $($and its executable name is: myshell$1)$ and run the program with the following input commands

date ; hostname ; uname $-$a

Is $-$I

Is $->>$ mydir.txt

Is $-$I $HOME $>$ myhome.txt

who $|$ grep 'whoami'

w $>$ myuser.txt ; w $|$ grep 'whoami'

listall

showme

Is $-$I myshell$1.$c

head myshell$1.$c

exit