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

diff --git a/doc/posix-functions/_setjmp.texi b/doc/posix-functions/_setjmp.texi
index 7c1dc32..abf1825 100644 (file)
--- a/doc/posix-functions/_setjmp.texi
+++ b/doc/posix-functions/_setjmp.texi
@@ -15,7 +15,10 @@ Portability problems not fixed by Gnulib:
 @item
 This function is missing on some platforms:
 Solaris 2.5.1.
-
-@item
-This function is obsolete; use @code{sigsetjmp} instead.
 @end itemize
+
+Note: A future revision of POSIX later than the 2008/2009 one may drop the
+functions @code{_setjmp} and @code{_longjmp}.  Still, in 2008, on all
+systems which have @code{_setjmp}, it is the fastest way to save the
+registers but not the signal mask (up to 30 times faster than @code{setjmp}
+on some systems).