On Mon, 12 Jun 2023, Frédéric Bérat via Libc-alpha wrote:

> @@ -56,7 +58,7 @@ tf (void *arg)
>  
>    /* This call should block and be cancelable.  */
>    char buf[20];
> -  read (fd[0], buf, sizeof (buf));
> +  xread (fd[0], buf, sizeof (buf));

Since the comment suggests this code is actually testing a property of the 
read function, it seems doubtful whether it's appropriate to change it to 
call xread - which would impose an API requirement on xread that it calls 
read in exactly the way under test.  Calling x* functions is fine in 
testcases when the function in question is not under test - for example, 
when the point of calling xread is just to read some data, with the 
details of how that's done being irrelevant - but questionable when the 
test is a test of read itself.

> @@ -32,7 +34,7 @@ tf (void *arg)
>      }
>  
>    char buf[10];
> -  read (fds[0], buf, sizeof (buf));
> +  xread (fds[0], buf, sizeof (buf));
>  
>    puts ("read returned");

The same might apply here.

-- 
Joseph S. Myers
joseph@codesourcery.com