#include #include #include #include /* Test code for 10.c */ int fd; void do_action(int cpu) { char buf[100]; int i; run_on_cpu(cpu); if(cpu == 0) write(fd, buf, sizeof(buf)); else read(fd, buf, sizeof(buf)); } main() { int status, retval, pid; char buf[100]; fd = open("foo", O_RDWR); assert(fd >= 0); if((pid=fork()) == 0) do_action(0); else { do_action(1); wait(&status); } }