sh(1posix) - shell, the standard command language interpreter
-c     Read commands from the command_string operand. Set the value of special parameter 0  (see  Special
       Parameters ) from the value of the command_name operand and the positional parameters ($1, $2, and
       so on) in sequence from the remaining argument operands.  No  commands  shall  be  read  from  the
       standard input.
-i     Specify  that  the  shell is interactive; see below. An implementation may treat specifying the -i
       option as an error if the real user ID of the calling process does not equal the effective user ID
       or if the real group ID does not equal the effective group ID.
-s     Read commands from the standard input.