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Date: Fri, 03 Sep 2021 00:57:16 +0200
From: Phil Krylov <phil@krylov.eu>
To: Ranier Vilela <ranier.vf@gmail.com>
Cc: Pg Hackers <pgsql-hackers@postgresql.org>
Subject: Re: [PATCH] pg_ctl should not truncate command lines at 1024
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On 2021-09-03 00:36, Ranier Vilela wrote:

> The msvc docs says that limit for the command line is 32,767 
> characters,
> while ok for me, I think if not it would be better to check this limit?

Well, it's ARG_MAX in POSIX, and ARG_MAX is defined as 256K in Darwin, 
512K in FreeBSD, 128K in Linux; _POSIX_ARG_MAX is defined as 4096 on all 
three platforms. Windows may differ too. Anyways, allocating even 128K 
in precious stack space is too much, that's why I suggest to use 
psprintf(). As for checking any hard limit, I don't think it would have 
much value - somehow we got the original command line, thus it is 
supported by the system, so we can just pass it on.

-- Ph.