Trent W. Buck <trentbuck@gmail.com> wrote:
I assume you're referring to SFTP's (and thus sshfs's) lack of support for locking. While annoying, IMO it's no worse than the locking issues I've run into with NFSv3 and Samba3, and I vaguely remember AFS has "advisory" locks (meaning it doesn't stop you).
Are there other places where SFTP doesn't comply with SUS 2008?
That's the right question to ask, and my quick Web search didn't locate a good attempt at an answer. As you note, locking issues are common to network-based file systems (in which regard, NFSv4 is an improvement, as I recall). The SSHFS FAQ indicates that rename operations are not implemented correctly, though there's a partially satisfactory work-around: http://sourceforge.net/apps/mediawiki/fuse/?title=SshfsFaq whereby the rename() is not atomic, but the link to an existing file/directory is removed. The rename(3posix) manual page reads, in part: "If the link named by the new argument exists, it shall be removed and old renamed to new. In this case, a link named new shall remain visible to other processes throughout the renaming operation and refer either to the file referred to by new or old before the operation began." I think that's what the FAQ is referring to.