Add return value checks for read & write calls in test_listmount_ns
function. This patch resolves below compilation warnings:

```
statmount_test_ns.c: In function ‘test_listmount_ns’:

statmount_test_ns.c:322:17: warning: ignoring return value of ‘write’
declared with attribute ‘warn_unused_result’ [-Wunused-result]

statmount_test_ns.c:323:17: warning: ignoring return value of ‘read’
declared with attribute ‘warn_unused_result’ [-Wunused-result]
```

Signed-off-by: Abhinav Jain <jain.abhinav177@gmail.com>
---
 .../selftests/filesystems/statmount/statmount_test_ns.c    | 7 +++++--
 1 file changed, 5 insertions(+), 2 deletions(-)

diff --git a/tools/testing/selftests/filesystems/statmount/statmount_test_ns.c b/tools/testing/selftests/filesystems/statmount/statmount_test_ns.c
index e044f5fc57fd..70cb0c8b21cf 100644
--- a/tools/testing/selftests/filesystems/statmount/statmount_test_ns.c
+++ b/tools/testing/selftests/filesystems/statmount/statmount_test_ns.c
@@ -319,8 +319,11 @@ static void test_listmount_ns(void)
 		 * Tell our parent how many mounts we have, and then wait for it
 		 * to tell us we're done.
 		 */
-		write(child_ready_pipe[1], &nr_mounts, sizeof(nr_mounts));
-		read(parent_ready_pipe[0], &cval, sizeof(cval));
+		if (write(child_ready_pipe[1], &nr_mounts, sizeof(nr_mounts)) !=
+					sizeof(nr_mounts))
+			ret = NSID_ERROR;
+		if (read(parent_ready_pipe[0], &cval, sizeof(cval)) != sizeof(cval))
+			ret = NSID_ERROR;
 		exit(NSID_PASS);
 	}
 
-- 
2.34.1

On 8/10/24 07:53, Abhinav Jain wrote:
> Add return value checks for read & write calls in test_listmount_ns
> function. This patch resolves below compilation warnings:
> 
> ```
> statmount_test_ns.c: In function ‘test_listmount_ns’:
> 
> statmount_test_ns.c:322:17: warning: ignoring return value of ‘write’
> declared with attribute ‘warn_unused_result’ [-Wunused-result]
> 
> statmount_test_ns.c:323:17: warning: ignoring return value of ‘read’
> declared with attribute ‘warn_unused_result’ [-Wunused-result]
> ```
> 
> Signed-off-by: Abhinav Jain <jain.abhinav177@gmail.com>
> ---
>   .../selftests/filesystems/statmount/statmount_test_ns.c    | 7 +++++--
>   1 file changed, 5 insertions(+), 2 deletions(-)
> 
> diff --git a/tools/testing/selftests/filesystems/statmount/statmount_test_ns.c b/tools/testing/selftests/filesystems/statmount/statmount_test_ns.c
> index e044f5fc57fd..70cb0c8b21cf 100644
> --- a/tools/testing/selftests/filesystems/statmount/statmount_test_ns.c
> +++ b/tools/testing/selftests/filesystems/statmount/statmount_test_ns.c
> @@ -319,8 +319,11 @@ static void test_listmount_ns(void)
>   		 * Tell our parent how many mounts we have, and then wait for it
>   		 * to tell us we're done.
>   		 */
> -		write(child_ready_pipe[1], &nr_mounts, sizeof(nr_mounts));
> -		read(parent_ready_pipe[0], &cval, sizeof(cval));
> +		if (write(child_ready_pipe[1], &nr_mounts, sizeof(nr_mounts)) !=
> +					sizeof(nr_mounts))
> +			ret = NSID_ERROR;
> +		if (read(parent_ready_pipe[0], &cval, sizeof(cval)) != sizeof(cval))
> +			ret = NSID_ERROR;
>   		exit(NSID_PASS);
>   	}
>   

Hi Christian,

Let me know if it is okay to take this patch through kselftest tree.
The change looks good to me.

thanks,
-- Shuah

On 8/16/24 07:11, Shuah Khan wrote:
> On 8/10/24 07:53, Abhinav Jain wrote:
>> Add return value checks for read & write calls in test_listmount_ns
>> function. This patch resolves below compilation warnings:
>>
>> ```
>> statmount_test_ns.c: In function ‘test_listmount_ns’:
>>
>> statmount_test_ns.c:322:17: warning: ignoring return value of ‘write’
>> declared with attribute ‘warn_unused_result’ [-Wunused-result]
>>
>> statmount_test_ns.c:323:17: warning: ignoring return value of ‘read’
>> declared with attribute ‘warn_unused_result’ [-Wunused-result]
>> ```
>>
>> Signed-off-by: Abhinav Jain <jain.abhinav177@gmail.com>
>> ---

> Hi Christian,
> 
> Let me know if it is okay to take this patch through kselftest tree.
> The change looks good to me.
> 
> thanks,
> -- Shuah

Thank you for the patch.

Applied to linux-kselftest next for Linux 6.12-rc1

thanks,
-- Shuah