On Thu, Oct 06, 2011 at 05:05:06PM -0600, Eric Blake wrote: > On 10/06/2011 05:01 PM, Michael Schwendt wrote: > >>> you would not notice any troubles. > >> > >> Umm, yes you would. That's not atomic, and risks leaving things in an > >> inconsistent state. > >> > >> http://www.flamingspork.com/talks/2007/06/eat_my_data.odp > >> http://www.pixelbeat.org/docs/unix_file_replacement.html > > > > cp -f ${grub_cfg}.new ${grub_cfg} ; rm -f ${grub_cfg}.new > > > > Better? > > No. cp is not atomic. I think that in this particular case you are overdoing that concern. These are small files and real writes are in blocks and not characters. > rename(2) (via mv(1), if both files are on the > same device) is. Any solution that does not use rename(2) is flawed, Only with this caveat that the current use of mv in grub2-mkconfig is not only flawed but also clearly completely broken. If you want to keep 'mv' then you first have to use 'readlink' on a target and replace that target if readlink returns a non-empty string. Why not after all? Something like that while target="$(readlink ${grub_cfg})" ; do grub_cfg="${target}" done in case you would have multilevel symlinks. Michal -- test mailing list test@xxxxxxxxxxxxxxxxxxxxxxx To unsubscribe: https://admin.fedoraproject.org/mailman/listinfo/test
