Need Help in Client and Server Programming in C - c

Question

I am coding a small C program to test the client and server programs so that the client sends an integer to the client. The server multiplies the number by 10 and returns the integer*10 back to the client. When writing the integers to the FIFO, use sizeof(int) as the number of bytes in the 3rd parameter of the write( ) and read( ).
That is my code so far:
The Client task:
#include <sys/types.h>
#include <sys/stat.h>
#include <unistd.h>
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <errno.h>
#include <fcntl.h>
main (void)
{
int fda; // to write to server
int fdb; // to read response from server
int number;
int outputnumber;
if((fda=open("FIFO_to_server", O_WRONLY))<0)
printf("cant open fifo to write");
if((fdb=open("FIFO_to_client", O_RDONLY))<0)
printf("cant open fifo to read");
printf("Client: Please enter an integer: ");
scanf("%d", &number);
write(fda, &number, sizeof(number));
printf("\nClient: Got the number sent, now waiting for response ");
read(fdb, &outputnumber, sizeof(outp utnumber));
printf("\nClient: received from server %s", outputnumber);
close(fda);
close(fdb);
printf ("\nall done!\n");
}
The server task:
#include <stdio.h>
#include <errno.h>
#include <fcntl.h>
main (void)
{
int fda; // to read from client
int fdb; // to write to client
int finish; // lets me know that client is done
int number;
int outputnumber;
/* Create the fifos and open them */
if ((mkfifo("FIFO_to_server",0666)<0 && errno != EEXIST))
{
perror("cant create FIFO_to_server");
exit(-1);
}
if ((mkfifo("FIFO_to_client",0666)<0 && errno != EEXIST))
{
perror("cant create FIFO_to_client");
exit(-1);
}
if((fda=open("FIFO_to_server", O_RDONLY))<0)
printf("cant open fifo to write");
if((fdb=open("FIFO_to_client", O_WRONLY))<0)
printf("cant open fifo to read");
finish=read(fda, number, sizeof(number)); //read the character
printf("Server: just got the number: ,%d", number));
outputnumber = 10*number;
write(fdb, outputnumber,sizeof(outputnumber));
printf("\nServer: Got the number sent");
if(finish == 1)
printf("\nServer: This says I am ready to close ");
close(fda);
close(fdb);
unlink("FIFO_to_server");
unlink("FIFO_to_client");
}
The Client's output show error:
-bash-3.2$ ./client
Client: Please enter an integer: 10
Client: Got the number sent, now waiting for response
Client: received from server ▒+▒▒▒▒▒▒7▒▒x}
all done!
The Server:
-bash-3.2$ ./server
Server: just got the number: 134614968
Server: Got the number sent-bash-3.2$