Received-SPF: pass (google.com: domain of linux-kernel-owner@vger.kernel.org designates 23.128.96.18 as permitted sender) client-ip=23.128.96.18;
Cc:     mtk.manpages@gmail.com, linux-man@vger.kernel.org,
        linux-kernel@vger.kernel.org, libc-alpha@sourceware.org
Subject: Re: [PATCH v3] getdents.2: Use appropriate types
To:     Alejandro Colomar <colomar.6.4.3@gmail.com>
References: <CAKgNAkgi7MAW9PxKNBFQ07r7p2PFRR3xU2BJBTqk8oiXDJ4NXA@mail.gmail.com>
 <20201029141053.195998-1-colomar.6.4.3@gmail.com>
From:   "Michael Kerrisk (man-pages)" <mtk.manpages@gmail.com>
Message-ID: <bbc1e527-23fd-855e-6a9f-acad1ed97bbd@gmail.com>
Date:   Thu, 29 Oct 2020 20:54:16 +0100
User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:78.0) Gecko/20100101
 Thunderbird/78.3.1
MIME-Version: 1.0
In-Reply-To: <20201029141053.195998-1-colomar.6.4.3@gmail.com>
Content-Type: text/plain; charset=utf-8
Content-Language: en-US
Content-Transfer-Encoding: 7bit
Precedence: bulk

On 10/29/20 3:10 PM, Alejandro Colomar wrote:
> getdents():
> This function has no glibc wrapper.
> As such, we should use the same types the Linux kernel uses:
> Use 'long' as the return type.
> 
> getdents64():
> The glibc wrapper uses:
> ssize_t getdents64(int, void *, size_t);
> 
> Signed-off-by: Alejandro Colomar <colomar.6.4.3@gmail.com>

Thanks, Alex. Applied.

Cheers,

Michael


> ---
> 
> Hi Michael,
> 
> Sorry, I'm being a bit distracted these days :)
> It should be good enough now, I think.
> 
> Cheers,
> 
> Alex
> 
>  man2/getdents.2 | 10 +++++-----
>  1 file changed, 5 insertions(+), 5 deletions(-)
> 
> diff --git a/man2/getdents.2 b/man2/getdents.2
> index a187fbcef..ed3bb40b1 100644
> --- a/man2/getdents.2
> +++ b/man2/getdents.2
> @@ -33,14 +33,13 @@
>  getdents, getdents64 \- get directory entries
>  .SH SYNOPSIS
>  .nf
> -.BI "int getdents(unsigned int " fd ", struct linux_dirent *" dirp ,
> +.BI "long getdents(unsigned int " fd ", struct linux_dirent *" dirp ,
>  .BI "             unsigned int " count );
>  .PP
>  .BR "#define _GNU_SOURCE" "        /* See feature_test_macros(7) */"
>  .B #include <dirent.h>
>  .PP
> -.BI "int getdents64(unsigned int " fd ", struct linux_dirent64 *" dirp ,
> -.BI "             unsigned int " count );
> +.BI "ssize_t getdents64(int " fd ", void *" dirp ", size_t " count );
>  .fi
>  .PP
>  .IR Note :
> @@ -282,7 +281,8 @@ struct linux_dirent {
>  int
>  main(int argc, char *argv[])
>  {
> -    int fd, nread;
> +    int fd;
> +    long nread;
>      char buf[BUF_SIZE];
>      struct linux_dirent *d;
>      char d_type;
> @@ -301,7 +301,7 @@ main(int argc, char *argv[])
>  
>          printf("\-\-\-\-\-\-\-\-\-\-\-\-\-\-\- nread=%d \-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\en", nread);
>          printf("inode#    file type  d_reclen  d_off   d_name\en");
> -        for (int bpos = 0; bpos < nread;) {
> +        for (long bpos = 0; bpos < nread;) {
>              d = (struct linux_dirent *) (buf + bpos);
>              printf("%8ld  ", d\->d_ino);
>              d_type = *(buf + bpos + d\->d_reclen \- 1);
> 


-- 
Michael Kerrisk
Linux man-pages maintainer; http://www.kernel.org/doc/man-pages/
Linux/UNIX System Programming Training: http://man7.org/training/