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From: Lawrence D'Oliveiro <ldo@nz.invalid>
Newsgroups: comp.lang.c
Subject: Re: Memory mapping: MAP_PRIVATE and msync()
Date: Mon, 8 Apr 2024 01:50:07 -0000 (UTC)
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On Sun, 07 Apr 24 15:18:47 +0000, pehache wrote:

> void* p2 = mmap( NULL
>                    , n
>                    , PROT_READ | PROT_WRITE
>                    , MAP_SHARED | MAP_NORESERVE
>                    , fd
>                    , 0 );

Not easy to remember what the arguments mean. Try this:

    void * p2 = mmap
      (
        /*addr =*/ NULL,
        /*length =*/ n,
        /*prot =*/ PROT_READ | PROT_WRITE,
        /*flags =*/ MAP_SHARED | MAP_NORESERVE,
        /*fd =*/ fd,
        /*offset =*/ 0
      );