link(2) to rename files in sftp

[Darren Tucker]

Carson Gaspar wrote:
> --On Tuesday, April 06, 2004 12:00:57 +1000 Darren Tucker wrote:
[about non-racy renames without clobbering existing files]
>> I have no idea how to implement that portably for filesystems without
>> Unix semantics without the race.
> 
> Well, if they are reasonably sane, you can do:
> 
> if (fd = open(newpath, O_CREAT|O_EXCL, 0)) {
>     ret = rename(oldpath, newpath);
>     close(fd);

> Unless I'm missing something...

For one thing, the Linux (RH9) open(2) man page says that 
O_CREATE|O_EXCL is racy on NFS filesystems.  Probably other platforms too.

-- 
Darren Tucker (dtucker at zip.com.au)
GPG key 8FF4FA69 / D9A3 86E9 7EEE AF4B B2D4  37C9 C982 80C7 8FF4 FA69
     Good judgement comes with experience. Unfortunately, the experience
usually comes from bad judgement.