On Sun, Feb 22, 2009 at 09:43:36PM -0500, Carlos O'Donell wrote: > flock is not POSIX, it's an interface invented by 4.2BSD, and was > previously emulated by glibc. The glibc wrapper implemented flock with > fcntl and made sure to return EWOULDBLOCK. > Right, I had confused flock and flockfile in the index. > > This is really going to suck, it looks like a lot of the locking > > primitives used EAGAIN and EWOULDBLOCK interchangeably... The fcntl > > manpage says 'EAGAIN or EWOULDBLOCK' so is flock(2) the only problem > > here? From a quick glance at posix, fcntl(2) returning EAGAIN is > > correct. > > I would warn you that the linux man pages are often incorrect. > > I use http://www.opengroup.org/onlinepubs/009695399/ for check POSIX > requirements. > I wouldn't be nearly so negative. > A more robust solution would be? > > if ((ret == -EAGAIN) || (ret == -EWOULDBLOK)) > ret = -EWOULDBLOCK > > This covers our ass since POSIX says that EAGAIN and EWOULDBLOCK *may* > be the same. > I have no idea what you're on about here, this is a parisc specific file, where we know they aren't. I don't want to pollute generic linux code with workarounds for moronic HPUX "let's be different for difference sake" crap. > > but somehow I suspect this interchangeable use of EAGAIN and EWOULDBLOCK > > is going to reveal latent problems in this part of the kernel I would > > rather not delve into... > > The ABI is fixed, so all we can do is cleanup the uses in the kernel, > and make sure we adhere to the documented APIs. > I ain't volunteering... > Don't get too upset ;-) -- To unsubscribe from this list: send the line "unsubscribe linux-arch" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
