Answer :
Answer:
client code:
#include <stdio.h>
#include <fcntl.h>
#include <sys/stat.h>
#include <sys/types.h>
#include <unistd.h>
#include <stdlib.h>
#include <string.h>
int main (void)
{
struct values
{
char privateFIFO[14];
int intbuff;
}input;
int fda; // common FIFO to read to write to server
int fdb; // Private FIFO to read from server
int clientID;
int retbuff;
char temp[14];
clientID = getpid();
strcpy(input.privateFIFO, "FIFO_");
sprintf(temp, "%d", clientID);
strcat(input.privateFIFO, temp);
printf("\nFIFO name is %s", input.privateFIFO);
// Open common FIFO to write to server
if((fda=open("FIFO_to_server", O_WRONLY))<0)
printf("cant open fifo to write");
write(fda, &input, sizeof(input)); // write the struct to the server
close(fda);
// Open private FIFO to read
if((fdb=open(input.privateFIFO, O_RDONLY))<0)
read(fdb, &retbuff, sizeof(retbuff));
printf("\nAll done\n");
close(fdb);
}
server code:
#include <stdio.h>
#include <errno.h>
#include <fcntl.h>
#include <sys/stat.h>
#include <sys/types.h>
#include <unistd.h>
#include <stdlib.h>
#include <string.h>
struct values
{
char privateFIFO[14];
int intbuff;
}input;
int main (void)
{
int fda; //common FIFO to read from client
int fdb; //private FIFO to write to client
int retbuff;
int output;
// create the common FIFO
if ((mkfifo("FIFO_to_server",0666)<0 && errno != EEXIST))
{
perror("cant create FIFO_to_server");
exit(-1);
}
// open the common FIFO
if((fda=open("FIFO_to_server", O_RDONLY))<0)
printf("cant open fifo to write");
output = read(fda, &input, sizeof(input));
// create the private FIFO
if ((mkfifo(input.privateFIFO, 0666)<0 && errno != EEXIST))
{
perror("cant create privateFIFO_to_server");
exit(-1);
}
printf("Private FIFO received from the client and sent back from server is: %d", output);
//open private FIFO to write to client
if((fdb=open(input.privateFIFO, O_WRONLY))<0)
printf("cant open fifo to read");
write(fdb, &retbuff, sizeof(retbuff));
close(fda);
unlink("FIFO_to_server");
close(fdb);
unlink(input.privateFIFO);
}
Explanation: