Added Process exercise's chapter

cons.c

@@ -0,0 +1,21 @@
+#include <stdio.h>
+#include <stdlib.h>
+#include <fcntl.h>
+#include <unistd.h>
+#include <sys/shm.h>
+#include <sys/mman.h>
+#include <sys/stat.h>
+
+int main()
+{
+  const int SIZE = 4096;
+  const char *name = "OS";
+
+  int shm_fd;
+  void *ptr;
+
+  shm_fd = shm_open(name, O_RDONLY, 0666);
+  ptr = mmap(0, SIZE, PROT_READ, MAP_SHARED, shm_fd, 0);
+  printf("%s", (char *)ptr);
+  shm_unlink(name);
+}