From mboxrd@z Thu Jan  1 00:00:00 1970
References: <56210E7E.1050606@siemens.com>
From: Jan Kiszka <jan.kiszka@siemens.com>
Message-ID: <5621102C.4030902@siemens.com>
Date: Fri, 16 Oct 2015 16:56:44 +0200
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Subject: Re: [Xenomai] Xenomai 3: kill() to non-Xenomai PIDs
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On 2015-10-16 16:49, Jan Kiszka wrote:
> Hi,
> 
> kill() is currently handled by libcobalt such that PIDs <= 0 are
> forwarded to Linux and PIDs > 0 are considered to target only Xenomai
> threads. But what if the user wants to address a regular Linux task from
> within a Xenomai application? Shouldn't we retry kill via the Linux path
> if Xenomai's syscall reports ESRCH?
> 

IOW:

diff --git a/lib/cobalt/signal.c b/lib/cobalt/signal.c
index aac4059..7e03301 100644
--- a/lib/cobalt/signal.c
+++ b/lib/cobalt/signal.c
@@ -99,6 +99,10 @@ COBALT_IMPL(int, kill, (pid_t pid, int sig))
 
 	ret = XENOMAI_SYSCALL2(sc_cobalt_kill, pid, sig);
 	if (ret) {
+		/* Retry with regular kill is no RT target was found. */
+		if (ret == -ESRCH)
+			return __STD(kill(pid, sig));
+
 		errno = -ret;
 		return -1;
 	}

Jan

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