From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: by sourceware.org (Postfix, from userid 2155) id 6E8E73858D33; Sun, 27 Aug 2023 12:35:17 +0000 (GMT) DKIM-Filter: OpenDKIM Filter v2.11.0 sourceware.org 6E8E73858D33 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=cygwin.com; s=default; t=1693139717; bh=bu/3eLQSiCw9FIlht9SC26nq0UOixUY1gwiJbrcrsz4=; h=Date:From:To:Subject:Reply-To:References:In-Reply-To:From; b=n3YgfGvxJPeNG+8s1PIRAGQY0uOl3BVxs1KAfe/Ymg64OqdR/aCMXg1FkD/SaNzGf uIgha5ah4Sn0/9j//rcM++Eyj2dJSHyNzWQMzxm0wvnsvCcvewjrGig9KUOb0PUPqP NFKqU/5o4nSIdYC8u6kM0NYSQ2AivToUM+HHRCFY= Received: by calimero.vinschen.de (Postfix, from userid 500) id 7F68FA8098F; Sun, 27 Aug 2023 14:35:15 +0200 (CEST) Date: Sun, 27 Aug 2023 14:35:15 +0200 From: Corinna Vinschen To: cygwin@cygwin.com Subject: Re: Documenting Cygwin on NFS, no longer only exchange-medium! Re: How to fix |mkfifo()| failure if |pathname| is on NFS ? / was: Re: [EXTERNAL] Re: mkfifo: cannot set permissions of 'x.fifo': Not a directory Message-ID: Reply-To: cygwin@cygwin.com Mail-Followup-To: cygwin@cygwin.com References: MIME-Version: 1.0 Content-Type: text/plain; charset=utf-8 Content-Disposition: inline Content-Transfer-Encoding: 8bit In-Reply-To: List-Id: On Aug 26 19:44, Martin Wege via Cygwin wrote: > On Fri, Aug 25, 2023 at 2:19 PM Corinna Vinschen via Cygwin > wrote: > > > > On Aug 23 01:05, Roland Mainz via Cygwin wrote: > > > Note that Cygwin does not interpret the file |myfifo.fifo| as FIFO, > > > instead it comes back as a symlink "myfifo.fifo -> ':\0:c4:1000'". > > > > > > AFAIK there are (at least) these two options to fix the problems: > > > 1. Check whether the filesystem for the fifos path is NFS > > > (cgywin.dll's |fs.fs_is_nfs()|), and if it is a symlink check if it > > > starts with ':\0:c4:' (assuming "c4" is the prefix for inodes created > > > with |mkfifo()|). If this condition is |true|, then cygwin |stat()|, > > > |open()| etc. should treat this inode as FIFO. > > > > The downside is that it is not possible to diffentiate between Cygwin > > FIFOs and real FIFOs created from the remote side in `ls -l' > > output. Note that Cygwin returns the NFS stat info verbatim, so > > a real FIFO is returned as a real FIFO: > > > > linux$ mkfifo bar > > cygwin$ ls -l bar > > prw-r--r-- 1 corinna vinschen 0 Aug 25 13:58 bar > > > > The idea was always to use NFS as exchange medium, but not as > > installation medium for the entire distro or to keep Cygwin home > > dirs on NFS. There were times where NFS was pretty unstable. > > I used NFS for quite some time to build Cygwin packages, but at one > > point I got trouble (performance problems with multiple concurrent > > processes accessing an NFS share, build errors out of the blue), > > so I switched to Samba shares, albeit grudgingly. I'm not yet > > sure if the problems are fixed. At least a recent OpenSSH build > > ran through without problems... > > Corinna, could you please update the Cygwin documentation then? We use > NFS, both Windows builtin and CITI NFSv4.1, with Cygwin for years > without major problems, so that comment about exchange-medium-only is > clearly wrong! I'm talking about the idea how users would use NFS, and the idea was that nobody in their right mind would use a crippled filesystem (from the Windows POV) for the entire installation. Before you came up with your complaints, nobody here even knew that somebody actually did that. NFS is a niche filesystem on Windows and was never in the focus of anybody here, except me, because I was toying around with it and was happy to have it working. As far as I knew until a few days ago, I was the only user of Cygwin's NFS support. As for FIFOs on NFS, as I wrote, they never worked as desired on NFS. For kicks I tried back until Cygwin 3.3. Given this isn't a regression, it won't be fixed for Cygwin 3.4. As Brian wrote in his reply to your mail, we are all volunteers here. Everybody working on Cygwin is working in their spare time and/or on the goodwill of their employer. Cygwin is open source. You can fix or implement stuff yourself and send the patches to the cygwin-patches ML for review. Otherwise you will have to let us, the people actually working on the project, decide when and how something gets implemented. Having said that, I have a local patch enabling FIFOs on NFS. I might push it at one point to the main branch, but the pressure you guys are currently building up on this mailing list puts me right off. Corinna