On Thu, Oct 13, 2011 at 10:05:05AM +0100, Pádraig Brady wrote: > Note the above is easier to express in shell like: > > [ -e "$file" ] || touch "$file"
Thanks, I'm familiar with it. :) > But that is racy. If you were using touch for locking purposes I'm using touch to make sure the file exists before an operation that will yield an error if it doesn't exist. For example: resolv=/etc/resolv.conf touch $resolv ci -l -t-$resolv -m"check-in existing" $resolv grep -q domain $resolv || echo domain $domain >> $resolv ci -l -m"add domain $domain" $resolv The intent of code like the above is to make sure a certain file is in revision control and contains a certain setting. If the file already is in revision control and has the setting, the code should do nothing. But touch changes the mtime. The problem could be fixed by slinging around ifs, but that's inelegant. - Morty
