From 10d2cc4ac9417cfb2f87c652e6cc4cf545c00bb8 Mon Sep 17 00:00:00 2001 From: Mike Brady <4265913+mikebrady@users.noreply.github.com> Date: Mon, 21 Jun 2021 20:46:26 +0100 Subject: [PATCH] Update README.md --- README.md | 7 +++---- 1 file changed, 3 insertions(+), 4 deletions(-) diff --git a/README.md b/README.md index 962149c..2c2e2bb 100644 --- a/README.md +++ b/README.md @@ -27,11 +27,10 @@ $ ./configure $ make # make install ``` -The `make install` creates the `nqptp` group and installs a `systemd` startup script. You should enable it and start it in the normal way. Note that `nqptp` must run in `root` mode to be able to access ports 319 and 320. +The `make install` installs a `systemd` startup script. You should enable it and start it in the normal way. Note that `nqptp` must run in `root` mode to be able to access ports 319 and 320. # Notes -A unix group called `nqptp` is created by the `make install` step. Members of this group have write access to the shared memory interface. -If you wish to use the shared mutex to ensure records are not altered while you are accessing them, you should open your side of the shared memory interface with read-write permission. Be aware that while your program has the mutex lock, it can halt `nqptp`, so keep any activity while you have the lock very short and very simple, e.g. copying it to local memory. +If you wish to use the shared mutex to ensure records are not altered while you are accessing them, you should open your side of the shared memory interface with read-write permission. Be aware that while your program has the mutex lock, it is in a "critical region" wherer it can halt `nqptp`, so keep any activity while you have the lock very short and very simple, e.g. copying it to local memory. Clock records not updated for a period are deleted. @@ -40,7 +39,7 @@ Since `nqptp` uses ports 319 and 320, it can not coexist with any other user of # Known Issues * It's probably buggy! * At present, `nqptp` does not take advantage of hardware timestamping. -* The daemon is Linux only, and has been developed and tested on a `systemd` Linux only. +* The daemon has been developed and tested on a `systemd` Linux only. # Things Can Change The `nqptp` daemon is under active development and, consequently, everything here can change, possibly very radically. -- 2.47.2