This is an automated email from the git hooks/post-receive script. guillem pushed a commit to branch main in repository dpkg.
View the commit online: https://git.dpkg.org/cgit/dpkg/dpkg.git/commit/?id=2bd0171aac3178bf193b1d8c26b6497b0b92241c commit 2bd0171aac3178bf193b1d8c26b6497b0b92241c Author: Guillem Jover <[email protected]> AuthorDate: Sun Oct 22 12:50:49 2023 +0200 man: Document the intermediary filenames used during unpack and configure There did not seem to be any explicit documentation anywhere about these filenames nor their functions. Prompted-by: Florian Weimer <[email protected]> Ref: https://sourceware.org/pipermail/libc-alpha/2023-October/152245.html --- man/dpkg.pod | 46 ++++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 46 insertions(+) diff --git a/man/dpkg.pod b/man/dpkg.pod index 8594e8e71..7effd8033 100644 --- a/man/dpkg.pod +++ b/man/dpkg.pod @@ -1448,6 +1448,52 @@ useful if it's lost or corrupted due to filesystems troubles. The format and contents of a binary package are described in L<deb(5)>. +=head2 Filesystem filenames + +During unpacking and configuration B<dpkg> uses various filenames for +backup and rollback purposes. +The following is a simplified explanation of how these filenames get used +during package installation. + +=over + +=item F<*.dpkg-new> + +During unpack, B<dpkg> extracts new filesystem objects into +I<pathname>B<.dpkg-new> +(except for existing directories or symlinks to directories which get skipped), +once that is done and after having performed backups of the old objects, +the objects get renamed to I<pathname>. + +=item F<*.dpkg-tmp> + +During unpack, B<dpkg> makes backups of the old filesystem objects into +I<pathname>B<.dpkg-tmp> after extracting the new objects. +These backups are performed as either a rename for directories +(but only if they switch file type), +a new symlink copy for symlinks, +or a hard link for any other filesystem object, +except for conffiles which get no backups because they are processed +at a later stage. + +In case of needing to rollback, these backups get used to restore the +previous contents of the objects. +These get removed automatically after the installation is complete. + +=item F<*.dpkg-old> + +During configuration, when installing a new version, +B<dpkg> cam make a backup of the previous modified conffile into +I<pathname>B<.dpkg-old>. + +=item F<*.dpkg-dist> + +During configuration, when keeping the old version, +B<dpkg> can make a backup of the new unmodified conffile into +I<pathname>B<.dpkg-dist>. + +=back + =head1 SECURITY Any operation that needs write access to the database or the filesystem -- Dpkg.Org's dpkg
