Provide more POSIX-complaint ttyname_r(3) interface[1], which is slightly

different from what has been offered in libc_r (the one spotted in the
original PR which is found in libthr has already been removed by David's
commit, which is rev. 1.44 of lib/libthr/thread/thr_private.h):
	- Use POSIX standard prototype for ttyname_r, which is,
		int ttyname_r(int, char *, size_t);
	  Instead of:
	  	char *ttyname_r(int, char *, size_t);
	  This is to conform IEEE Std 1003.1, 2004 Edition [1].
	- Since we need to use standard errno for return code, include
	  errno.h in ttyname.c
	- Update ttyname(3) implementation according to reflect the API
	  change.
	- Document new ttyname_r(3) behavior
	- Since we already make use of a thread local storage for
	  ttyname(3), remove the BUGS section.
	- Remove conflicting ttyname_r related declarations found in libc_r.

Hopefully this change should not have changed the API/ABI, as the ttyname_r
symbol was never introduced before the last unistd.h change which happens a
couple of days before.

[1] http://www.opengroup.org/onlinepubs/009695399/functions/ttyname.html

Requested by:	Tom McLaughlin <tmclaugh sdf lonestar org>
Through PR:	threads/76938
Patched by:	Craig Rodrigues <rodrigc crodrigues org> (with minor changes)
Prompted by:	mezz@

1 files changed, 1 insertions, 1 deletions

diff --git a/include/unistd.h b/include/unistd.h
index c56fb4f11b41..9bc7af71e27f 100644
--- a/include/unistd.h
+++ b/include/unistd.h
@@ -365,7 +365,7 @@ long	 sysconf(int);
 pid_t	 tcgetpgrp(int);
 int	 tcsetpgrp(int, pid_t);
 char	*ttyname(int);
-char	*ttyname_r(int, char *, size_t);
+int	ttyname_r(int, char *, size_t);
 int	 unlink(const char *);
 ssize_t	 write(int, const void *, size_t);