[PATCH RESEND] lib/vsprintf: Improve vsprintf + sprintf function comments

[PATCH RESEND] lib/vsprintf: Improve vsprintf + sprintf function comments

[Thorsten Blum]

Clarify that the return values of vsprintf() and sprintf() exclude the
trailing NUL character.

Signed-off-by: Thorsten Blum <thorsten.blum@linux.dev>
---
 lib/vsprintf.c | 8 ++++----
 1 file changed, 4 insertions(+), 4 deletions(-)

diff --git a/lib/vsprintf.c b/lib/vsprintf.c
index eb0cb11d0d12..e49f350ee549 100644
--- a/lib/vsprintf.c
+++ b/lib/vsprintf.c
@@ -3054,8 +3054,8 @@ EXPORT_SYMBOL(scnprintf);
  * @fmt: The format string to use
  * @args: Arguments for the format string
  *
- * The function returns the number of characters written
- * into @buf. Use vsnprintf() or vscnprintf() in order to avoid
+ * The return value is the number of characters written into @buf not including
+ * the trailing '\0'. Use vsnprintf() or vscnprintf() in order to avoid
  * buffer overflows.
  *
  * If you're not already dealing with a va_list consider using sprintf().
@@ -3074,8 +3074,8 @@ EXPORT_SYMBOL(vsprintf);
  * @fmt: The format string to use
  * @...: Arguments for the format string
  *
- * The function returns the number of characters written
- * into @buf. Use snprintf() or scnprintf() in order to avoid
+ * The return value is the number of characters written into @buf not including
+ * the trailing '\0'. Use snprintf() or scnprintf() in order to avoid
  * buffer overflows.
  *
  * See the vsnprintf() documentation for format string extensions over C99.
-- 
2.51.1

Re: [PATCH RESEND] lib/vsprintf: Improve vsprintf + sprintf function comments

[Andy Shevchenko]

On Mon, Nov 03, 2025 at 10:09:13AM +0100, Thorsten Blum wrote:
> Clarify that the return values of vsprintf() and sprintf() exclude the
> trailing NUL character.

I dunno if we need this clarification, but I'm not against it either, FWIW,
Reviewed-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
if it helps somebody.

-- 
With Best Regards,
Andy Shevchenko

Re: [PATCH RESEND] lib/vsprintf: Improve vsprintf + sprintf function comments

[Thorsten Blum]

On 3. Nov 2025, at 10:42, Andy Shevchenko wrote:
> On Mon, Nov 03, 2025 at 10:09:13AM +0100, Thorsten Blum wrote:
>> Clarify that the return values of vsprintf() and sprintf() exclude the
>> trailing NUL character.
> 
> I dunno if we need this clarification, but I'm not against it either, FWIW,
> Reviewed-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
> if it helps somebody.

Thanks. It would have helped me :)

Re: [PATCH RESEND] lib/vsprintf: Improve vsprintf + sprintf function comments

[Petr Mladek]

On Mon 2025-11-03 10:09:13, Thorsten Blum wrote:
> Clarify that the return values of vsprintf() and sprintf() exclude the
> trailing NUL character.
> 
> Signed-off-by: Thorsten Blum <thorsten.blum@linux.dev>

Looks good to me:

Reviewed-by: Petr Mladek <pmladek@suse.com>

Best Regards,
Petr

PS: I am sorry that the first email somehow slipped though the cracks.

Re: [PATCH RESEND] lib/vsprintf: Improve vsprintf + sprintf function comments

[Petr Mladek]

On Mon 2025-11-03 10:09:13, Thorsten Blum wrote:
> Clarify that the return values of vsprintf() and sprintf() exclude the
> trailing NUL character.
> 
> Signed-off-by: Thorsten Blum <thorsten.blum@linux.dev>

JFYI, the patch has been comitted into printk/linux.git,
branch for-6.19.

Best Regards,
Petr

PS: The patch was trivial so I was not waiting for any additional
    feedback. And better to do not forget about the patch again ;-)