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@linux.dev>
Reviewed-by: Petr Mladek <pmladek@suse.com>
Reviewed-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Link: https://patch.msgid.link/20251103090913.2066-2-thorsten.blum@linux.dev
Signed-off-by: Petr Mladek <pmladek@suse.com>

diff --git a/lib/vsprintf.c b/lib/vsprintf.c
index eb0cb11d0d126f02d8884b3ebbcdcf75beb8a621..e49f350ee549de9b06ac21c364279814d52d26c1 100644 (file)
--- 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.