man/man2/kill.2: RETURN VALUE: Fix wording issue with sig=0

The DESCRIPTION says:

	If *sig* is 0, then no signal is sent, but existence and
	permission checks are still performed; this can be used to
	check for the existence of a process ID.

On the other hand, the `RETURN VALUE` section contradicted that.

	On success (at least one signal was sent), zero is returned.  On
	error, -1 is returned...

How can I get 0 when providing sig=0, if no signal was actually
sent, which is the criteria for success of this call???

Reported-by: Amit Pinhas <amitpinhass@gmail.com>
Co-authored-by: Alejandro Colomar <alx@kernel.org>
Signed-off-by: Amit Pinhas <amitpinhass@gmail.com>
Message-ID: <a4fa37e0fc89a3c99982ace3fe381991ebe85b00.1739393685.git.amitpinhass@gmail.com>
Signed-off-by: Alejandro Colomar <alx@kernel.org>

diff --git a/man/man2/kill.2 b/man/man2/kill.2
index 96468622e7216ab73b386e66264dea346f00a8bb..9d3a7411eaf04321b16daeeff9e12af129887d4d 100644 (file)
--- a/man/man2/kill.2
+++ b/man/man2/kill.2
@@ -79,7 +79,9 @@ it suffices when the sending and receiving
 processes belong to the same session.
 (Historically, the rules were different; see HISTORY.)
 .SH RETURN VALUE
-On success (at least one signal was sent), zero is returned.
+On success, zero is returned.
+If signals were sent to a process group,
+success means that at least one signal was delivered.
 On error, \-1 is returned, and
 .I errno
 is set to indicate the error.