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// -----------------------------------------------------------------------------
// Pipes
//
// Write a program that creates a child process and pipes the string
// "hello child" to the child to be printed. The parent should wait for the
// child to terminate
//
// Template: Implement the TODOs
//
// Expected output:
// Parent Sending: hello child
// Child Received: hello child
// -----------------------------------------------------------------------------
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <sys/wait.h>
#include <unistd.h>
int main(void) {
// Open pipe
int ends[2];
pipe(ends);
char string_to_send[] = "hello child";
int bytes_to_send_recv = strlen(string_to_send) + 1;
// Create child process
pid_t pid = fork();
if (pid < 0) {
// Error
fprintf(stderr, "ERROR: Failed to fork\n");
}
else if (pid > 0) {
// Parent
printf("Parent Sending: %s\n", string_to_send);
// Parent doesn't need read file descriptor
close(ends[0]);
// Write the string to the pipe
write(ends[1], string_to_send, bytes_to_send_recv);
// Done writing
close(ends[1]);
// Wait for child to terminate
wait(NULL);
}
else {
// Child
char *recv_buffer = malloc(bytes_to_send_recv);
// Child doesn't need write file descriptor
close(ends[1]);
// Read the string from the pipe
read(ends[0], recv_buffer, bytes_to_send_recv);
// Done reading
close(ends[0]);
// Print result
printf("Child Received: %s\n", recv_buffer);
free(recv_buffer);
}
return 0;
}
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