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Date: Tue, 8 Jul 2014 23:07:27 +0200
From: Jilles Tjoelker <jilles@stack.nl>
To: Bryan Drewery <bdrewery@FreeBSD.org>
Subject: Re: sys/proc.h inclusion of sys/time.h
Message-ID: <20140708210727.GA63071@stack.nl>
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On Tue, Jul 08, 2014 at 03:06:33PM -0500, Bryan Drewery wrote:
> In r34924 sys/proc.h was changed to only include sys/time.h if not 
> building in kernel.

> [snip]

> (Why am I doing this? I need PID_MAX and NO_PID for a tcpdump change I 
> am testing that is intended for upstreaming. Perhaps I can use 
> kern.pid_max in __FreeBSD__ and other hacks on other platforms, I have 
> not yet decided on this.)

The kern.pid_max sysctl is mostly intended for running FreeBSD 1.0
binaries, which have a 16-bit pid_t. Therefore, it is run-time
adjustable and existing processes may have a pid higher than its value.

Ideally, you do not need PID_MAX and NO_PID; try to use a variable of
type pid_t only for a process ID and store flags elsewhere. There may be
a problem if you need to read pid_t from an internal structure or
message, though.

-- 
Jilles Tjoelker