hpux man page for _lwp_kill

_lwp_kill(2)							System Calls Manual						      _lwp_kill(2)

NAME
       _lwp_kill() - send a signal to an LWP (Lightweight Process)

SYNOPSIS
DESCRIPTION
       The function sends a signal to the LWP target_lwp.  The target_lwp can be in any process.  is the LWP equivalent of kill().

       The  signal  to	be  sent is specified by sig and is either one from the list given in signal(5), or 0.	If sig is (the null signal), error
       checking is performed but no signal is actually sent.  This can be used to check the validity of the LWP target_lwp.

       If the LWP target_lwp is in another process, the real or effective user ID of the sending process must match the real or saved user  ID	of
       the receiving process unless the effective user ID of the sending process is a user who has appropriate privileges.

       If the signal action for sig specifies termination, stop or continue, the entire process is terminated, stopped or continued, respectively.

       Uncatchable signals (for example, SIGKILL and SIGSTOP) cannot be sent to an LWP in the init process.

       Signals cannot be sent to kernel daemon threads and helper threads created internally by the HP-UX system.

RETURN VALUE
       Upon  successful  completion,  returns with a value of 0; otherwise, it returns an error number to indicate the error.  The variable is NOT
       set if an error occurs.

ERRORS
       If any of the following conditions occur, the function fails and returns the corresponding error number:

	      sig    is neither a valid signal number nor zero.

	      sig    is SIGKILL or SIGSTOP and target_lwp is an LWP in the process with pid (proc1).

	      The caller does not have the necessary privileges.

	      No LWP can be found with the identity
		     target_lwp.

WARNINGS
       In general, the POSIX pthread interfaces should be used by multi-threaded applications.	This system call may be used  directly	only  when
       the  application has a need to operate on LWPs in another process.  This system call may result in undefined behavior if the usage is mixed
       with POSIX pthread APIs.

SEE ALSO
       kill(1), _lwp_self(2), kill(2), sigaction(2), pthread_kill(3T), signal(5).

																      _lwp_kill(2)