#ifndef CRYPT$\_$H

#define CRYPT$\_$H

#define MAX$\_$BUFF $1024$

#define STDIN $0$

#define STDOUT $1$

#define STDERR $2$

void client$($int readfd $/*$read head of channel $*/,$ int writefd $/*$write head of channel $*/)$;

void server$($int readfd $/*$read head of channel $*/,$ int writefd $/*$write head of channel $*/)$;

double calculate$($char $*$buf$)$;

#endif

#include

#include

#include

#include

#include

#include

#include

int main$($int argc, char $**$argv$)\{$

$/*************************************************************$

write code for the main process that will establish

the communication channel between cleint and server using

pipes

$*************************************************************/$

pid$\_$t pid;

$//$ TODO:

int fd$[2]$;

int pipe$($int pipefd$[2])$;

if$($pipe$($fd$)=0)\{$

printf$("$Hello$"$

$)$;

exit$(-1)$;

$\}$

pid $=$ fork$()$;

if$($pid $<0)\{$

perror$("$Fork failed

$")$;

return $1$;

$\}$

if$($pid $==0)\{$

$//$ TODO:

$//$call to server here: server$($int readfd, int writefd$)$;

exit$(0)$;

$\}$

$//$ TODO:

$//$call to client here client$($int readfd, int writefd$)$;

return $0$;

$\}$

#include

#include

#include

#include

#include

#include

#include

void client$($int readfd, int writefd$)\{$

$/*************************************************************$

write client code to be used by the parent process

$*************************************************************/$

char buf$[$MAX$\_$BUFF$]$;

size$\_$t len;

$//$ implement client functionality

$\}$

#include

#include

#include

#include

#include

#include

#include

void server$($int readfd, int writefd$)\{$

$/*************************************************************$

write server code to be used by the child process

$*************************************************************/$

char buf$[$MAX$\_$BUFF$]$;

size$\_$t len;

$/*$ Implement server functionlity here

use calculate function to evaluate expression

signature: calculate$($char $*$buf$)$

$*/$

$\}$

#include

#include

#include

#include

#include

#include

#include

double calculate$($char $*$buf$)\{$

$/*************************************************************$

Implement the expression evaluation functionality which

will be invoked by the server whenever required.

$*************************************************************/$

double operands$[20]$;

char op$[20]$;

int oprnInd $=0$;

double result $=0\mathrm{.}0$;

$//$ implement expression evaluation functionality here

return$($result$)$;

$\}$