coreutils/TODO

restore djgpp, eventually
merge TODO lists
add unit tests for lib/*.c
rewrite lib/ftw.c not to use explicit recursion, and then use nftw in
  chown, chgrp, chmod, du

strip: add an option to specify the program used to strip binaries.
  suggestion from Karl Berry

doc/coreutils.texi:
  Address this comment: FIXME: mv's behavior in this case is system-dependent
  Better still: fix the code so it's *not* system-dependent.

implement --target-directory=DIR for install (per texinfo documentation)

ls: add --format=FORMAT option that controls how each line is printed.

cp --no-preserve=X should not attempt to preserve attribute X
  reported by Andreas Schwab

copy.c: Address the FIXME-maybe comment in copy_internal.
And once that's done, add an exclusion so that `cp --link'
no longer incurs the overhead of saving src. dev/ino and dest. filename
in the hash table.

See if we can be consistent about where --verbose sends its output:
  These all send --verbose output to stdout:
    head, tail, rm, cp, mv, ln, chmod, chown, chgrp, install, ln
  These send it to stderr:
    shred mkdir split
  readlink is different

Write an autoconf test to work around build failure in HPUX's 64-bit mode.
See notes in README -- and remove them once there's a work-around.

Integrate use of sendfile, suggested here:
  http://mail.gnu.org/archive/html/bug-fileutils/2003-03/msg00030.html
I don't plan to do that, since a few tests demonstrate no significant benefit.

Should printf '\0123' print "\n3"?
  per report from TAKAI Kousuke on Mar 27
  http://mail.gnu.org/archive/html/bug-coreutils/2003-03/index.html

printf: consider adapting builtins/printf.def from bash

df: add `--total' option, suggested here http://bugs.debian.org/186007

seq: give better diagnostics for invalid formats:
   e.g. no or too many % directives
seq: consider allowing format string to contain no %-directives

dd: consider adding an option to suppress `bytes/block read/written'
output to stderr.  Suggested here:
  http://bugs.debian.org/cgi-bin/bugreport.cgi?bug=165045

m4: rename all macros that start with AC_ to start with another prefix

resolve RH report on cp -a forwarded by Tim Waugh

Martin Michlmayr's patch to provide ls with `--sort directory' option

tail: don't use xlseek; it *exits*.
  Instead, maybe use a macro and return nonzero.

add mktemp?  Suggested by Nelson Beebe

Now that AC_FUNC_LSTAT and AC_FUNC_STAT are in autoconf,
remove m4/stat.m4 and m4/lstat.m4.

df: alignment problem of `Used' heading with e.g., -mP
  reported by Karl Berry

tr: support nontrivial equivalence classes, e.g. [=e=] with LC_COLLATE=fr_FR

fix tail -f to work with named pipes; reported by Ian D. Allen
  $ mkfifo j; tail -f j & sleep 1; echo x > j
  ./tail: j: file truncated
  ./tail: j: cannot seek to offset 0: Illegal seek

lib/strftime.c: Since %N is the only format that we need but that
  glibc's strftime doesn't support, consider using a wrapper that
  would expand /%(-_)?\d*N/ to the desired string and then pass the
  resulting string to glibc's strftime.

sort: Compress temporary files when doing large external sort/merges.
  This improves performance when you can compress/uncompress faster than
  you can read/write, which is common in these days of fast CPUs.
  suggestion from Charles Randall on 2001-08-10

sort: Add an ordering option -R that causes 'sort' to sort according
  to a random permutation of the correct sort order.  Also, add an
  option --random-seed=SEED that causes 'sort' to use an arbitrary
  string SEED to select which permutations to use, in a deterministic
  manner: that is, if you sort a permutation of the same input file
  with the same --random-seed=SEED option twice, you'll get the same
  output.  The default SEED is chosen at random, and contains enough
  information to ensure that the output permutation is random.
  suggestion from Feth AREZKI, Stephan Kasal, and Paul Eggert on 2003-07-17

unexpand: [http://www.opengroup.org/onlinepubs/007908799/xcu/unexpand.html]
  printf 'x\t \t y\n'|unexpand -t 8,9 should print its input, unmodified.
  printf 'x\t \t y\n'|unexpand -t 5,8 should print "x\ty\n"

Let GNU su use the `wheel' group if appropriate.
  (there are a couple patches, already)

sort: Investigate better sorting algorithms; see Knuth vol. 3.

  We tried list merge sort, but it was about 50% slower than the
  recursive algorithm currently used by sortlines, and it used more
  comparisons.  We're not sure why this was, as the theory suggests it
  should do fewer comparisons, so perhaps this should be revisited.
  List merge sort was implemented in the style of Knuth algorithm
  5.2.4L, with the optimization suggested by exercise 5.2.4-22.  The
  test case was 140,213,394 bytes, 426,4424 lines, text taken from the
  GCC 3.3 distribution, sort.c compiled with GCC 2.95.4 and running on
  Debian 3.0r1 GNU/Linux, 2.4GHz Pentium 4, single pass with no
  temporary files and plenty of RAM.

  Since comparisons seem to be the bottleneck, perhaps the best
  algorithm to try next should be merge insertion.  See Knuth section
  5.3.1, who credits Lester Ford, Jr. and Selmer Johnson, American
  Mathematical Monthly 66 (1959), 387-389.

doc/coreutils.texi:
  Document the exit status of each and every program.
  Suggestion from Dan Jacobson.
  The sentence or two describing the common case must appear just once,
  and then it must be made to appear in the 70+ places where it's needed.

du: rewrite to use something other than nftw to perform directory traversal.
  Due to design limitations of nftw, ...
    using -D makes du dereference each command
    line argument that is a symlink to a directory.
    A symlink to non-directory is not dereferenced.

cp --recursive: perform dir traversals in source and dest hierarchy rather
  than forming full file names.  The latter (current) approach fails
  unnecessarily when the names become very long.

`tail --follow=name --retry' should elicit a diagnostic, since no file name
  was specified.