Re: kernel bug in socketpair()

[Glenn Fowler <gsf@research.att.com>]

On Wed, 23 Jul 2003 12:14:36 -0700 David S. Miller wrote:
> I missed the reason why you can't use pipes and bash
> is able to, what is it?

we have some applications, ksh included, with semantics that require
stdin be read at most one line at a time; an inefficient implementation
of this does 1 byte read()s until newline is read; an efficient
implementation does a peek read (without advancing the read/seek offset),
determines how many chars to read up to and including the newline,
and then read()s that much

linux has ioctl(I_PEEK) for stream devices and recv() for sockets,
and neither of these work on pipes; if there is a linux alternative
for pipes then we'd be glad to use it

we switched from pipe() to socketpair() to take advantage of the linux
recv() peek read