the option in pkg_create. Now preserved files start with a . and are
named .<filename>.<pkgname>.backup so that their purpose is more clear.
Note that just using the preserve option without proper pkg_deps
is also foolish since packages being deleted in the incorrect order with
preserve on can generate some odd results.
before replacing them (using pkgname to make this hopefully unique).
Delete also moves them back, if they exist, resulting in a package
which can be "backed out" with reasonable safety.
This will make a number of things easier in the future, as well as (finally!)
avoiding the Id-smashing problem which has plagued developers for so long.
Boy, I'm glad we're not using sup anymore. This update would have been
insane otherwise.
later at pkg_delete time to verify that you're deleting what you added.
This, of course, does NOT cover the case where a file you still need
hasn't changed! That's a tougher problem to solve, and this provides
only the minimal amount of safety belt. MD5 checksums are stored in comment
fields, so packages produced with these tools are backwards compatible with
the older ones.
2. Fix a long-standing bug in pkg_add where the failure of one package in
a multipackage installation (pkg_add *.tgz) would blow you right out of
the water. Ick.
