O_NDELAY versus O_NONBLOCK

[Joel Sherrill]

Chris Faylor wrote:
> 
> On Sun, Sep 03, 2000 at 01:15:13PM -0500, Joel Sherrill wrote:
> >
> >Simple question.  They have different values in newlib but
> >appear to have the same meaning.  Under Linux, they have
> >the same value.
> >
> >What should newlib do?  If they are supposed to be treated semantically
> >the same, then can they be the same value?
> 
> That's a good question.  I notice that cygwin sporadically attempts to test
> both values but it isn't consistent.

This is the same thing inside RTEMS.  I started tracked down a 
problem with fcntl and it turned out to be that the path did not
check one of the part.

> Having them equal makes sense to me.

In starting to fix this, I came across another similar constant --
FNBIO.  I don't even see it in the Linux headers, so it can't
be that important. :)  Regardless, should this one be the same
value as well -- or does it have different semantics?

Regardless, attached is a patch that makes O_NDELAY and O_NONBLOCK 
the same.

2000-09-05	Joel Sherrill <joel@OARcorp.com>

	* libc/include/fcntl.h: Make O_NDELAY and O_NONBLOCK
	have the same value.


 
> cgf

-- 
Joel Sherrill, Ph.D.             Director of Research & Development
joel@OARcorp.com                 On-Line Applications Research
Ask me about RTEMS: a free RTOS  Huntsville AL 35805
   Support Available             (256) 722-9985
--- ../original/newlib-1.8.2/newlib/libc/include/sys/fcntl.h	Mon Apr 26 20:22:30 1999
+++ newlib-1.8.2/newlib/libc/include/sys/fcntl.h	Tue Sep  5 08:13:42 2000
@@ -20,7 +20,7 @@
 #define	_FEXCL		0x0800	/* error on open if file exists */
 #define	_FNBIO		0x1000	/* non blocking I/O (sys5 style) */
 #define	_FSYNC		0x2000	/* do all writes synchronously */
-#define	_FNONBLOCK	0x4000	/* non blocking I/O (POSIX style) */
+#define	_FNONBLOCK	_FNDELAY /* non blocking I/O (POSIX style) */
 #define	_FNOCTTY	0x8000	/* don't assign a ctty on this open */
 
 #define	O_ACCMODE	(O_RDONLY|O_WRONLY|O_RDWR)