docs: mention cygwin shortcoming in <sys/un.h>

[gnulib.git] / doc / posix-headers / unistd.texi

diff --git a/doc/posix-headers/unistd.texi b/doc/posix-headers/unistd.texi
index 855eefb..7beb4c2 100644 (file)
--- a/doc/posix-headers/unistd.texi
+++ b/doc/posix-headers/unistd.texi
@@ -1,14 +1,15 @@
 @node unistd.h
 @section @file{unistd.h}
 
-POSIX specification: @url{http://www.opengroup.org/susv3xbd/unistd.h.html}
+POSIX specification:@* @url{http://www.opengroup.org/onlinepubs/9699919799/basedefs/unistd.h.html}
 
 Gnulib module: unistd
 
 Portability problems fixed by Gnulib:
 @itemize
 @item
-This header file is missing on some platforms: msvc.
+This header file is missing on some platforms:
+MSVC 9.
 @item
 The SEEK_* macros are not defined in this file on some platforms:
 mingw.
@@ -18,6 +19,11 @@ OS/2 EMX, mingw.
 @item
 The @code{_exit} function is not declared in this file on some platforms:
 mingw.
+
+@item
+Some platforms provide a @code{NULL} macro that cannot be used in arbitrary
+expressions:
+NetBSD 5.0
 @end itemize
 
 Portability problems not fixed by Gnulib: