$//$ Verify the provided command$-$line argument and execute respective action

if $($strcmp$($argv$[1],"-$ux$")==0||$ strcmp$($argv$[1],"-$ur$")==0||$ strcmp$($argv$[1],"-$uw$")==0||$

strcmp$($argv$[1],"-$gx$")==0||$ strcmp$($argv$[1],"-$gr$")==0||$ strcmp$($argv$[1],"-$gw$")==0||$

strcmp$($argv$[1],"-$ox$")==0||$ strcmp$($argv$[1],"-$or$")==0||$ strcmp$($argv$[1],"-$ow$")==0)\{$

print$\_$files$\_$with$\_$permission$($argv$[3],$ argv$[1])$;

$\}$ else $\{$

printf$("$Invalid command$-$line argument

$")$;

return $1$;

$\}$