linux-kernel - [PATCH] lib/vsprintf: Improve vsprintf + sprintf function comments

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Message-ID: <20251007141905.202067-2-thorsten.blum@linux.dev>
Date: Tue,  7 Oct 2025 16:19:06 +0200
From: Thorsten Blum <thorsten.blum@...ux.dev>
To: Petr Mladek <pmladek@...e.com>,
	Steven Rostedt <rostedt@...dmis.org>,
	Andy Shevchenko <andriy.shevchenko@...ux.intel.com>,
	Rasmus Villemoes <linux@...musvillemoes.dk>,
	Sergey Senozhatsky <senozhatsky@...omium.org>,
	Andrew Morton <akpm@...ux-foundation.org>
Cc: Thorsten Blum <thorsten.blum@...ux.dev>,
	linux-kernel@...r.kernel.org
Subject: [PATCH] lib/vsprintf: Improve vsprintf + sprintf function comments

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

Signed-off-by: Thorsten Blum <thorsten.blum@...ux.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.
-- 
2.51.0