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/****************************************************************
*
* Purpose: Basic example of pipe.
* Read and write variable length records across a pipe.
*
* Author: M J Leslie
*
* Date: 17 Apr 96
*
****************************************************************/
#include <sys/types.h>
#include <unistd.h> /* pipe. */
#include <signal.h>
void Child (pid_t Handle);
void Parent (pid_t Handle);
main()
{
pid_t Pid;
int fd[2];
pipe(fd); /* Create two file descriptors */
Pid = fork();
if ( Pid == 0) /* Child */
{
close(fd[0]);
Child(fd[1]);
puts("Child end");
}
else /* Parent */
{
close(fd[1]);
Parent(fd[0]);
puts("Parent end");
}
}
/****************************************************************
*
* The Child sends data to the parent.
*
****************************************************************/
void Child(pid_t Handle)
{
int Len;
char Buff[50]="Bass Beer";
Len = strlen(Buff)+1;
write(Handle, &Len, sizeof(Len));
write(Handle, Buff, Len);
strcpy(Buff, "Wild times.");
Len = strlen(Buff)+1;
write(Handle, &Len, sizeof(Len));
write(Handle, Buff, Len);
strcpy(Buff, "Alex was ere.");
Len = strlen(Buff)+1;
write(Handle, &Len, sizeof(Len));
write(Handle, Buff, Len);
strcpy(Buff, "Bon Jovi rules the world.");
Len = strlen(Buff)+1;
write(Handle, &Len, sizeof(Len));
write(Handle, Buff, Len);
close(Handle);
}
/****************************************************************
*
* Read the data sent by the child.
*
****************************************************************/
void Parent(pid_t Handle)
{
int Len;
char Buff[50];
/* ... Perform two reads. THe first gets the length of the data
... the second gets the actual data. */
while (read(Handle, &Len, sizeof(Len)) > 0)
{
read(Handle,Buff, Len);
printf("%s\n", Buff);
}
}
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