Provided by: bup-doc_0.25-1_all bug


       bup-index - print and/or update the bup filesystem index


       bup  index <-p|-m|-s|-u> [-H][-l] [-x][\--fake-valid] [--no-check-device][\--fake-invalid]
       [--check][\--clear]      [-f      indexfile][\--exclude      *path*]       [--exclude-from
       filename][\--exclude-rx *pattern*] [-v] <filenames...>


       bup index  prints  and/or  updates  the  bup  filesystem  index,  which  is a cache of the
       filenames, attributes, and sha-1 hashes of each file and directory in the filesystem.  The
       bup   index   is   similar  in  function  to  the  git(1)  index,  and  can  be  found  in

       Creating a backup in bup consists of two steps: updating the index  with  bup index,  then
       actually  backing  up  the files (or a subset of the files) with bup save.  The separation
       exists for these reasons:

       1. There is more than one way to generate a list of files that need to be backed up.   For
          example, you might want to use inotify(7) or dnotify(7).

       2. Even  if  you  back  up files to multiple destinations (for added redundancy), the file
          names, attributes, and hashes will be the same each  time.   Thus,  you  can  save  the
          trouble of repeatedly re-generating the list of files for each backup set.

       3. You  may want to use the data tracked by bup index for other purposes (such as speeding
          up other programs that need the same information).


       bup makes accommodations for the expected "worst-case" filesystem timestamp resolution  --
       currently  one  second;  examples  include  VFAT,  ext2, ext3, small ext4, etc.  Since bup
       cannot know  the  filesystem  timestamp  resolution,  and  could  be  traversing  multiple
       filesystems  during  any given run, it always assumes that the resolution may be no better
       than one second.

       As a practical matter, this means that index updates are a bit imprecise, and so  bup save
       may occasionally record filesystem changes that you didn't expect.  That's because, during
       an index update, if bup encounters a path whose actual timestamps are more recent than one
       second  before  the update started, bup will set the index timestamps for that path (mtime
       and ctime) to exactly one second before the run, -- effectively capping those values.

       This ensures that no subsequent changes to those paths can result in timestamps  that  are
       identical  to  those  in  the  index.   If  that  were  possible,  bup  could overlook the

       You can see the effect of this behavior in this example (assume that less than one  second
       elapses between the initial file creation and first index run):

              $ touch src/1 src/2
              # A "sleep 1" here would avoid the unexpected save.
              $ bup index src
              $ bup save -n src src  # Saves 1 and 2.
              $ date > src/1
              $ bup index src
              $ date > src/2         # Not indexed.
              $ bup save -n src src  # But src/2 is saved anyway.

       Strictly  speaking,  bup  should  not  notice the change to src/2, but it does, due to the
       accommodations described above.


       -u, --update
              recursively update the index for the given filenames and their descendants.  One or
              more filenames must be given.  If no mode option is given, this is the default.

       -p, --print
              print  the  contents of the index.  If filenames are given, shows the given entries
              and their descendants.  If no filenames are given, shows the  entries  starting  at
              the current working directory (.).

       -m, --modified
              prints  only files which are marked as modified (ie.  changed since the most recent
              backup) in the index.  Implies -p.

       -s, --status
              prepend a status code (A, M, D, or space) before each filename.  Implies  -p.   The
              codes  mean,  respectively,  that a file is marked in the index as added, modified,
              deleted, or unchanged since the last backup.


       -H, --hash
              for each file printed, prepend the most recently recorded hash code.  The hash code
              is  normally generated by bup save.  For objects which have not yet been backed up,
              the hash code will be 0000000000000000000000000000000000000000.  Note that the hash
              code  is  printed  even if the file is known to be modified or deleted in the index
              (ie.  the file on the filesystem no longer matches the recorded hash).  If this  is
              a problem for you, use --status.

       -l, --long
              print  more  information  about  each file, in a similar format to the -l option to

       -x, --xdev, --one-file-system
              don't cross filesystem boundaries when  recursing  through  the  filesystem.   Only
              applicable if you're using -u.

              mark specified filenames as up-to-date even if they aren't.  This can be useful for
              testing, or to avoid unnecessarily backing up files that you know are boring.

              mark specified filenames as not up-to-date, forcing the  next  "bup  save"  run  to
              re-check their contents.

              carefully  check index file integrity before and after updating.  Mostly useful for
              automated tests.

              clear the default index.

       -f, --indexfile=indexfile
              use a different index filename instead of $BUP_DIR/bupindex.

              exclude path from the backup; bup will not expand path in any way (can be used more
              than once).

              read --exclude paths from filename, one path per-line (can be used more than once).

              exclude  any  path  matching  pattern,  which  must  be a Python regular expression
              (  The pattern will be compared against the
              full  path,  without  anchoring,  so "x/y" will match "ox/yard" or "box/yards".  To
              exclude the contents of /tmp, but not the directory itself, use "^/tmp/.".  (can be
              specified more than once)


              · '/foo$' - exclude any file named foo

              · '/foo/$' - exclude any directory named foo

              · '/foo/.' - exclude the content of any directory named foo

              · '^/tmp/.' - exclude root-level /tmp's content, but not /tmp itself

              don't  mark a an entry invalid if the device number (stat(2) st_dev) changes.  This
              can be useful when indexing remote, automounted, or (LVM) snapshot filesystems.

       -v, --verbose
              increase log output during update (can be used more than once).  With one -v, print
              each directory as it is updated; with two -v, print each file too.


              bup index -vux /etc /var /usr


       bup-save(1), bup-drecurse(1), bup-on(1)


       Part of the bup(1) suite.


       Avery Pennarun <>.