| 71 |
|
* |
| 72 |
|
* If the second argument is 1, the call won't block when |
| 73 |
|
* results aren't ready, but will immediately return 0. |
| 74 |
– |
* (A special value of -1 returns 0 unless a ray is |
| 75 |
– |
* ready in the queue and no system calls are needed.) |
| 74 |
|
* If the second argument is 0, the call will block |
| 75 |
|
* until a value is available, returning 0 only if the |
| 76 |
< |
* queue is completely empty. A negative return value |
| 76 |
> |
* queue is completely empty. Setting the second argument |
| 77 |
> |
* to -1 returns 0 unless a ray is ready in the queue and |
| 78 |
> |
* no system calls are needed. A negative return value |
| 79 |
|
* indicates that a rendering process died. If this |
| 80 |
|
* happens, ray_pclose(0) is automatically called to close |
| 81 |
|
* all child processes, and ray_pnprocs is set to zero. |
| 480 |
|
if (r_proc[ray_pnprocs].pid < 0) |
| 481 |
|
error(SYSTEM, "cannot fork child process"); |
| 482 |
|
close(p1[0]); close(p0[1]); |
| 483 |
+ |
if (rand_samp) /* desynchronize random function */ |
| 484 |
+ |
srandom((long)r_proc[ray_pnprocs].pid); |
| 485 |
|
/* |
| 486 |
|
* Close write stream on exec to avoid multiprocessing deadlock. |
| 487 |
|
* No use in read stream without it, so set flag there as well. |
| 508 |
|
if (inclose) |
| 509 |
|
return; |
| 510 |
|
inclose++; |
| 511 |
+ |
/* check no child / in child */ |
| 512 |
+ |
if (ray_pnprocs <= 0) |
| 513 |
+ |
return; |
| 514 |
|
/* check argument */ |
| 515 |
|
if ((nsub <= 0) | (nsub > ray_pnprocs)) |
| 516 |
|
nsub = ray_pnprocs; |
