cambda@xxxxxxxxxxxxxxxxx writes: > I found syscall kill() can send signal to a thread id, which is > not the TGID. But the Linux manual page kill(2) said: > > "The kill() system call can be used to send any signal to any > process group or process." > > And the Linux manual page tkill(2) said: > > "tgkill() sends the signal sig to the thread with the thread ID > tid in the thread group tgid. (By contrast, kill(2) can be used > to send a signal only to a process (i.e., thread group) as a > whole, and the signal will be delivered to an arbitrary thread > within that process.)" > > I don't know whether the meaning of this 'process' should be > the TGID? Because I found kill(tid, 0) will return ESRCH on FreeBSD, > while Linux sends signal to the thread group that the thread belongs > to. > > If this is as expected, should we add a notice to the Linux manual > page? Because it's a syscall and the pids not equal to tgid are not > listed under /proc. This may be a little confusing, I guess. How did you come across this? Were you just experimenting? I am wondering if you were tracking a bug, or a portability problem or something else. If the current behavior is causing problems in some way instead of just being a detail that no one really cares about either way it would be worth considering if we want to maintain the current behavior. Eric
