Hey guys, i have an assignment for my perl class which is the following:

Create a pipe
Fork a sub-process
Parent gets a message from the user, sends it to the child
Child gets the message, prints it to the screen
Repeat until user doesn't enter a message

This is what I have so far and cant seem to get it to work properly, please help me with this simple code!

 

pipe(PIPE_READ,PIPE_WRITE);
autoflush PIPE_WRITE 1;
my $pid = fork();
if ($pid = fork) {
  &write_pipe ($pid); 
  waitpid($pid,0); 
} 
elsif (defined $pid) {
  &read_pipe;         
}
else {
  die "cannot fork: $!";
}

sub write_pipe {
    print "pid $$ \n";
    print "Enter message: ";
    sleep 1;
    my $usr_msg = <>;
    print "Parent pid = $$  message = $usr_msg";
    print PIPE_WRITE "$usr_msg\n";
}

sub read_pipe {
    print "child pid = $pid";
    my $msg_read = <PIPE_READ>;
    
    print "received from pipe $msg_read";
}

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In reply to Creating a Pipe by grjoe21

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