log10f-ieee: Work around test failure on NetBSD 5.1.

[gnulib.git] / doc / posix-functions / isascii.texi

diff --git a/doc/posix-functions/isascii.texi b/doc/posix-functions/isascii.texi
index 19a7037..72312ea 100644 (file)
--- a/doc/posix-functions/isascii.texi
+++ b/doc/posix-functions/isascii.texi
@@ -2,7 +2,7 @@
 @section @code{isascii}
 @findex isascii
 
-POSIX specification: @url{http://www.opengroup.org/susv3xsh/isascii.html}
+POSIX specification:@* @url{http://www.opengroup.org/onlinepubs/9699919799/functions/isascii.html}
 
 Gnulib module: ---
 
@@ -13,3 +13,18 @@ Portability problems fixed by Gnulib:
 Portability problems not fixed by Gnulib:
 @itemize
 @end itemize
+
+Note: This function's behaviour depends on the locale, but requires special
+handling for the multibyte characters that occur in strings in locales with
+@code{MB_CUR_MAX > 1} (this includes all the common UTF-8 locales).
+There are two alternative APIs:
+
+@table @code
+@item c_isascii
+This function operates in a locale independent way and returns true only for
+ASCII characters.  It is provided by the Gnulib module @samp{c-ctype}.
+
+@item mb_isascii
+This function operates in a locale dependent way, on multibyte characters.
+It is provided by the Gnulib module @samp{mbchar}.
+@end table