linux-kernel - Re: [PATCH v2] selftests: splice: Add usage() to splice

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [<thread-prev] [day] [month] [year] [list]

Message-ID: <52a6d4ab-99a4-46b3-bd43-58054602d86b@linuxfoundation.org>
Date: Tue, 3 Sep 2024 16:07:53 -0600
From: Shuah Khan <skhan@...uxfoundation.org>
To: Rong Tao <rtoax@...mail.com>, shuah@...nel.org
Cc: rongtao@...tc.cn,
 "open list:KERNEL SELFTEST FRAMEWORK" <linux-kselftest@...r.kernel.org>,
 open list <linux-kernel@...r.kernel.org>,
 Shuah Khan <skhan@...uxfoundation.org>
Subject: Re: [PATCH v2] selftests: splice: Add usage() to splice_read.c

On 8/30/24 23:14, Rong Tao wrote:
> From: Rong Tao <rongtao@...tc.cn>
> 
> Give the programmer more help information to inform the program on how to
> use it.
> 
> Signed-off-by: Rong Tao <rongtao@...tc.cn>
> ---
>   tools/testing/selftests/splice/splice_read.c | 9 ++++++++-
>   1 file changed, 8 insertions(+), 1 deletion(-)
> 
> diff --git a/tools/testing/selftests/splice/splice_read.c b/tools/testing/selftests/splice/splice_read.c
> index 46dae6a25cfb..73a8bc146f97 100644
> --- a/tools/testing/selftests/splice/splice_read.c
> +++ b/tools/testing/selftests/splice/splice_read.c
> @@ -9,6 +9,12 @@
>   #include <sys/types.h>
>   #include <sys/stat.h>
>   
> +void usage(const char *prog)
> +{
> +	fprintf(stderr, "Usage: %s INPUT [BYTES]\n", prog);
> +	fprintf(stderr, "       %s /etc/os-release | cat\n", prog);

How does replacing %s INPUT [BYTES]\n", prog with /etc/os-release | cat\n" do?
Also what happens on distros that don't have os-release file?

> +}
> +
>   int main(int argc, char *argv[])
>   {
>   	int fd;
> @@ -16,7 +22,7 @@ int main(int argc, char *argv[])
>   	ssize_t spliced;
>   
>   	if (argc < 2) {
> -		fprintf(stderr, "Usage: %s INPUT [BYTES]\n", argv[0]);
> +		usage(argv[0]);
>   		return EXIT_FAILURE;
>   	}
>   
> @@ -49,6 +55,7 @@ int main(int argc, char *argv[])
>   		      size, SPLICE_F_MOVE);
>   	if (spliced < 0) {
>   		perror("splice");
> +		usage(argv[0]);
>   		return EXIT_FAILURE;
>   	}
>   

I don't understand how this change helps user.

thanks,
-- Shuah