26 lines
465 B
C
26 lines
465 B
C
|
// Demonstrate lack of fairness in IPC.
|
||
|
|
// Start three instances of this program as envs 1, 2, and 3.
|
||
|
|
// (user/idle is env 0).
|
||
|
|
|
||
|
|
#include <inc/lib.h>
|
||
|
|
|
||
|
|
void
|
||
|
|
umain(int argc, char **argv)
|
||
|
|
{
|
||
|
|
envid_t who, id;
|
||
|
|
|
||
|
|
id = sys_getenvid();
|
||
|
|
|
||
|
|
if (thisenv == &envs[1]) {
|
||
|
|
while (1) {
|
||
|
|
ipc_recv(&who, 0, 0);
|
||
|
|
cprintf("%x recv from %x\n", id, who);
|
||
|
|
}
|
||
|
|
} else {
|
||
|
|
cprintf("%x loop sending to %x\n", id, envs[1].env_id);
|
||
|
|
while (1)
|
||
|
|
ipc_send(envs[1].env_id, 0, 0, 0);
|
||
|
|
}
|
||
|
|
}
|
||
|
|
|