Path: utzoo!attcan!uunet!seismo!sundc!pitstop!sun!decwrl!labrea!agate!pasteur!ames!elroy!spl1!laidbak!katzung
From: katzung@laidbak.UUCP (Brian Katzung)
Newsgroups: comp.os.minix
Subject: Re: new and improved freopen.c (I hope)
Summary: Bugs, extensions, 1 opinion on naming
Message-ID: <1782@laidbak.UUCP>
Date: 14 Nov 88 17:09:03 GMT
References: <260@cst.UUCP>
Reply-To: katzung@laidbak.UUCP (Brian Katzung)
Organization: Lachman Associates, Inc., Naperville, Illinois
Lines: 45

In article <260@cst.UUCP> meulenbr@cst.UUCP (Frans Meulenbroeks) writes:
>X#define  PMODE    0644

Shouldn't this be 0666 so that umask can be used to get the desired mode?

>X	flags = flags & !WRITEMODE & !READMODE;

That sets all bits to zero (perhaps those are network-mangled tildas??).
I believe you meant

	flags &= ~(WRITEMODE | READMODE);

>X	case 'a': 
>X		flags |= WRITEMODE;
>X		if (( fd = open(name,1)) < 0 )
>X			return((FILE *)NULL);
>X		lseek(fd,0L,2);
>X		break;         

Append is really two attempts:

	if ((fd = open(name, 1)) < 0 && (fd = creat(name, PMODE)) < 0)
		return ((FILE *) NULL);

Does Minix support O_APPEND mode?  If not, perhaps there needs to be
an APPENDMODE bit (see flame below) to achieve nearly the same effect.
The only reference I have handy right now (SVID) guarantees writes at
the end.

Do the original routines support r+, w+, and a+ modes?  These are nice
to have.  I'm not near a Minix machine at the moment.  Does Minix support
open with 3 arguments?  This would make an implementation a little
easier/cleaner.

>Frans Meulenbroeks        (meulenbr@cst.prl.philips.nl)
>	Centre for Software Technology
>	( or try: ...!mcvax!philmds!prle!cst!meulenbr)

VERY small flame/spark (but not aimed at Frans) on a related topic:
Aren't READMODE and WRITEMODE rather "central" in the name-space
for "semi-invisible" definitions?  It seems to me that something
like _SIO_READ and _SIO_WRITE might have been a bit less likely to
collide with application definitions.

-- Brian Katzung  ...!spl1!laidbak!katzung