Re: [PATCH] 2.4.19-pre3 - readv/writev should return EINVAL for count=0

[Alex Riesen <Alexander.Riesen@synopsys.com>]

may be not. SunOS, HPUX, and AIX return EINVAL (unless it's their libc).
Maybe it is useful for compatibility with read/write.
And it's not really an error, after all, whereas EINVAL also means
overflow (sum of all iovec's longer than ssize_t) for readv/writev.
-alex

On Thu, Mar 21, 2002 at 07:28:50AM -0600, Paul Larson wrote:
> On Thu, 2002-03-21 at 01:34, Alex Riesen wrote:
> > I would disagree. According to the spec "The iovcnt argument is valid
> > if greater than 0 and less than or equal to {IOV_MAX}, as defined in
> > <limits.h>" (http://www.opengroup.org/onlinepubs/007904975/).
> > The behaviour you want to achieve is described as optional, besides
> > there is programs depending on the old behaviour (of my own at least :).
> > It's very handy to skip extra zero-parameter check...
> > -alex
> ^-This is the one I was referring to.  Is there any reason for it to not
> be in compliance with this?
> "The iovcnt argument is valid if greater than 0 and less than or equal to {IOV_MAX}, as defined in
>  <limits.h>" (http://www.opengroup.org/onlinepubs/007904975/)
> 
> Sorry, I just noticed that there was a previous thread here in which a
> patch was submitted by balbir_soni@yahoo.com.  I think the same person
> who started it might have been the same person that pointed out that one
> of our LTP testcases was passing when it shouldn't be and brought it to
> my attention.  It doesn't look like that thread got resolved though.
> 
> Paul Larson