I'm packaging a new release of lftp. The default config file (/etc/lftp.conf) is slightly different from the one in the previous release. This raises a problem: how should I determine whether to replace the old config file? There are at least three approaches, in increasing order of complexity:
(1) Copy the new default config in only if none already exists: [ -e /etc/lftp.conf ] || cp /etc/defaults/etc/lftp.conf /etc I've used this approach in my other packages, e.g. orpie. Gerrit, I think it was, told me it was a bug, but looking around I see that some other packages also use it. It's simple, but anyone who's ever installed lftp before won't get the new default config file. (2) Ask the user what they want to do, if /etc/lftp.conf already exists. It seems to me that this could get to be quite elaborate; if I'm going to ask the user what they want to do, then I need to offer them some good alternatives, e.g. look at the diffs. If this is the preferred method for Cygwin, then I shouldn't be writing it ad hoc. We should develop a standard postinstall script or shell function to handle it. (3) Compute a checksum of the current /etc/lftp.conf, and compare it to the checksum of the old default. If they're the same, then the user hasn't touched the old default so copy the new default in. If they're different, then prompt the user as in (2). So we need to store checksums of default config files somewhere. This is Debian's method. Again if this is the preferred method, then someone should develop a standard method to handle it. Is one of these approaches, or some other one, preferred for Cygwin? Or is it up to my discretion? Thanks, Andrew.
