From: fruktopus@gmail.com (Stephan Müller)
To: kernelnewbies@lists.kernelnewbies.org
Subject: what is the use of #ifndefs
Date: Mon, 20 Jul 2015 18:03:39 +0200 [thread overview]
Message-ID: <55AD1BDB.6030805@gmail.com> (raw)
In-Reply-To: <CA+KS1kZMibbMKwo2n15+EEtZs4P_MpVTXPpiwgxohWgo9OhKeQ@mail.gmail.com>
The keyword is 'include guard'
~frukto
Am 20.07.2015 um 17:55 schrieb leo kirotawa:
> it means you don't want to redefine a .h file
>
> On Mon, Jul 20, 2015 at 7:03 AM, Ahmed Soliman
> <ahmedsoliman0x666@gmail.com> wrote:
>> currently I started reading through the linux kernel and I started
>> reading liunx/include/linux/list.h> I understood some of the functions
>> but still I dont know what does these lines of code do
>> #ifndef _LINUX_LIST_H
>> #define _LINUX_LIST_H
>> which exist at the very beginning of the file
>> I also noticed that there is many similar ifndefs in almost any .h
>> file in the kernel
>> note that I understand wnat does ifndef do bu I dont understand what
>> goal is it supposed to achieve at the beginning of the headerfile
>>
>> _______________________________________________
>> Kernelnewbies mailing list
>> Kernelnewbies at kernelnewbies.org
>> http://lists.kernelnewbies.org/mailman/listinfo/kernelnewbies
>
>
>
next prev parent reply other threads:[~2015-07-20 16:03 UTC|newest]
Thread overview: 11+ messages / expand[flat|nested] mbox.gz Atom feed top
2015-07-20 10:03 what is the use of #ifndefs Ahmed Soliman
2015-07-20 15:55 ` leo kirotawa
2015-07-20 16:03 ` Stephan Müller [this message]
2015-07-20 16:11 ` Greg Freemyer
2015-07-20 17:00 ` anish singh
2015-07-21 2:24 ` Navy
2015-07-21 5:05 ` Raul Piper
2015-07-21 5:34 ` Amit Pandey
2015-07-21 7:01 ` Navy
2015-07-21 8:33 ` Bernd Petrovitsch
2015-07-21 19:44 ` Aruna Hewapathirane
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