Mail Archives: cygwin-developers/2001/03/25/16:47:58
----- Original Message -----
From: "Egor Duda" <deo AT logos-m DOT ru>
Subject: Re: setup will have to wait :[
> Hi!
>
> Saturday, 24 March, 2001 Robert Collins robert DOT collins AT itdomain DOT com DOT au
wrote:
>
> RC> 1. Do "non-unix" apps understand the concept of a FIFO file?
>
> directly -- not, but they can possibly inherit, say, stdout handle
> from parent cygwin process, and it can possibly be a handle of fifo.
> For example, you run
> "sh -c ./some-script.sh >fifo-to-script-log-processor"
> and 'some-script.sh' contains non-cygwin apps
Right, so _how do we pass the fd_ to the child process? I'll look into
spawn and fork. Worst case though: fifos are cygwin only. Best case I
find some way of tricking the OS into loading up the cygwin code and
writing "through it". Hmm I wonder if an IFS could do this (How much
work did I think this was going to be ?!).
> RC> I know that cygwin already has named pipe support
>
> ? what do you mean by this? do you mean native calls such as
> CreateNamedPipe () etc. or something else?
From comments about sshd and cvs on 9x and the syncronisation problems -
so I may be off base. I haven't checked the code. Implementing this via
Named Pipes will be just as tricky as far as non-cygwin programs though
won't it?.
> RC> so is there any reason to try and make FIFO support interoperate
> RC> (and what should it appear as?)
>
> RC> 2. Do you have a reference? So far I've found lots of sys/stat.h
header
> RC> files :]. If you don't are writes and reads atomic?
>
> no, at least i don't think that they must be.
>
> RC> Do all readers recieve all the same data from each writer -
>
> no, every byte written to fifo is read by only one reader, though it
> can be anyone of them.
>
> RC> or do they pair off? (That sounds rather dirty I know :])
>
> i generally use linux and freebsd as reference. just logon to the
> nearest linux box and try :) i've also found it quite helpful to look
> into linux and/or bsd kernel sources to understand how things work.
>
> Egor. mailto:deo AT logos-m DOT ru ICQ 5165414 FidoNet
2:5020/496.19
>
Well I've only got an openBSD boxen handy. I'll write up a four way test
script and see what it does.
Rob
- Raw text -