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[4.1.11]
* `rm symlink-to-unwritable' doesn't prompt [introduced in 4.1.10]
[4.1.10]
* rm once again gives a reasonable diagnostic when failing to remove a file
    owned by someone else in a sticky directory [introduced in 4.1.9]
* df now rounds all quantities up, as per POSIX.
* New ls time style: long-iso, which generates YYYY-MM-DD HH:MM.
* Any time style can be preceded by "posix-"; this causes "ls" to
  use traditional timestamp format when in the POSIX locale.
* The default time style is now posix-long-iso instead of posix-iso.
  Set TIME_STYLE="posix-iso" to revert to the behavior of 4.1.1 thru 4.1.9.
* `rm dangling-symlink' doesn't prompt [introduced in 4.1.9]
* stat: remove support for --secure/-s option and related %S and %C format specs
* stat: rename --link/-l to --dereference/-L.
    The old options will continue to work for a while.
[4.1.9]
* rm can now remove very deep hierarchies, in spite of any limit on stack size
* new programs: link, unlink, and stat
* New ls option: --author (for the Hurd).
* `touch -c no-such-file' no longer fails, per POSIX
[4.1.8]
* mv no longer mistakenly creates links to preexisting destination files
    that aren't moved
[4.1.7]
* rm: close a hole that would allow a running rm process to be subverted
[4.1.6]
* New cp option: --copy-contents.
* cp -r is now equivalent to cp -R.  Use cp -R -L --copy-contents to get the
  traditional (and rarely desirable) cp -r behavior.
* ls now accepts --time-style=+FORMAT, where +FORMAT works like date's format
* The obsolete usage `touch [-acm] MMDDhhmm[YY] FILE...' is no longer
  supported on systems conforming to POSIX 1003.1-2001.  Use touch -t instead.
* cp and inter-partition mv no longer give a misleading diagnostic in some
    unusual cases
[4.1.5]
* cp -r no longer preserves symlinks
* The block size notation is now compatible with SI and with IEC 60027-2.
  For example, --block-size=1MB now means --block-size=1000000,
  whereas --block-size=1MiB now means --block-size=1048576.
  A missing `B' (e.g. `1M') has the same meaning as before.
  A trailing `B' now means decimal, not binary; this is a silent change.
  The nonstandard `D' suffix (e.g. `1MD') is now obsolescent.
* -H or --si now outputs the trailing 'B', for consistency with the above.
* Programs now output trailing 'K' (not 'k') to mean 1024, as per IEC 60027-2.
* New df, du short option -B is short for --block-size.
* You can omit an integer `1' before a block size suffix,
  e.g. `df -BG' is equivalent to `df -B 1G' and to `df --block-size=1G'.
* The following options are now obsolescent, as their names are
  incompatible with IEC 60027-2:
   df, du: -m or --megabytes (use -BM or --block-size=1M)
   df, du, ls: --kilobytes (use --block-size=1K)
[4.1.4]
* df --local no longer lists smbfs file systems whose name starts with //
* dd now detects the Linux/tape/lseek bug at run time and warns about it.
[4.1.3]
* ls -R once again outputs a blank line between per-directory groups of files.
    This was broken by the cycle-detection change in 4.1.1.
* dd once again uses `lseek' on character devices like /dev/mem and /dev/kmem.
    On systems with the linux kernel (at least up to 2.4.16), dd must still
    resort to emulating `skip=N' behavior using reads on tape devices, because
    lseek has no effect, yet appears to succeed.  This may be a kernel bug.
[4.1.2]
* cp no longer fails when two or more source files are the same;
    now it just gives a warning and doesn't copy the file the second time.
    E.g., cp a a d/ produces this:
    cp: warning: source file `a' specified more than once
* chmod would set the wrong bit when given symbolic mode strings like
    these: g=o, o=g, o=u.  E.g., `chmod a=,o=w,ug=o f' would give a mode
    of --w-r---w- rather than --w--w--w-.
[4.1.1]
* mv (likewise for cp), now fails rather than silently clobbering one of
    the source files in the following example:
    rm -rf a b c; mkdir a b c; touch a/f b/f; mv a/f b/f c
* ls -R detects directory cycles, per POSIX.  It warns and doesn't infloop.
* cp's -P option now means the same as --no-dereference, per POSIX.
    Use --parents to get the old meaning.
* When copying with the -H and -L options, cp can preserve logical
    links between source files with --preserve=links
* cp accepts new options:
    --preserve[={mode,ownership,timestamps,links,all}]
    --no-preserve={mode,ownership,timestamps,links,all}
* cp's -p and --preserve options remain unchanged and are equivalent
    to `--preserve=mode,ownership,timestamps'
* mv and cp accept a new option: --reply={yes,no,query};  provides a consistent
    mechanism to control whether one is prompted about certain existing
    destination files.  Note that cp's and mv's -f options don't have the
    same meaning: cp's -f option no longer merely turns off `-i'.
* remove portability limitations (e.g., PATH_MAX on the Hurd, fixes for
    64-bit systems)
* mv now prompts before overwriting an existing, unwritable destination file
    when stdin is a tty, unless --force (-f) is specified, as per POSIX.
* mv: fix the bug whereby `mv -uf source dest' would delete source,
    even though it's older than dest.
* chown's --from=CURRENT_OWNER:CURRENT_GROUP option now works
* cp now ensures that the set-user-ID and set-group-ID bits are cleared for
    the destination file when when copying and not preserving permissions.
* `ln -f --backup k k' gives a clearer diagnostic
* ls no longer truncates user names or group names that are longer
    than 8 characters.
* ls's new --dereference-command-line option causes it to dereference
  symbolic links on the command-line only.  It is the default unless
  one of the -d, -F, or -l options are given.
* ls -H now means the same as ls --dereference-command-line, as per POSIX.
* ls -g now acts like ls -l, except it does not display owner, as per POSIX.
* ls -n now implies -l, as per POSIX.
* ls can now display dates and times in one of four time styles:

  - The `full-iso' time style gives full ISO-style time stamps like
    `2001-05-14 23:45:56.477817180 -0700'.
  - The 'iso' time style gives ISO-style time stamps like '2001-05-14 '
    and '05-14 23:45'.
  - The 'locale' time style gives locale-dependent time stamps like
    'touko  14  2001' and 'touko  14 23:45' (in a Finnish locale).
  - The 'posix-iso' time style gives traditional POSIX-locale
    time stamps like 'May 14  2001' and 'May 14 23:45' unless the user
    specifies a non-POSIX locale, in which case it uses ISO-style dates.
    This is the default.

  You can specify a time style with an option like --time-style='iso'
  or with an environment variable like TIME_STYLE='iso'.  GNU Emacs 21
  and later can parse ISO dates, but older Emacs versions cannot, so
  if you are using an older version of Emacs outside the default POSIX
  locale, you may need to set TIME_STYLE="locale".

* --full-time is now an alias for "-l --time-style=full-iso".

Changes in release 4.1:
[4.0.45]
* dd conv=sync,block now pads only with spaces
* ls's -1 option no longer cancels the effect of a preceding -l
* regenerate configure using a patched version of autoconf-2.49e to work
    around a bug in its test for a working memcmp function
* ls: fix off-by-one error introduced with the previous change
[4.0.44]
* ls: When given two or more arguments but the only one that exists is a
    directory, don't treat it as if it were the only argument.  Before,
    `mkdir d; ls no-dir d 2>/dev/null' would act like `ls d' and produce
    no output.  Now, it prints `d:'.
* touch -d 'last friday' would use a time stamp that was one hour off
    (e.g., 23:00 on *thursday* rather than 00:00 of the preceding friday)
    when run such that the current time and the target date/time fall on
    opposite sides of a daylight savings time transition.
    This problem arises only with relative date strings like `last monday'.
    It is not a problem with strings that include absolute dates.
[4.0.43]
* regenerate configure-related files using autoconf-2.49d
[4.0.42]
* Using ls's short-named `-H' option evokes the warning that the
   meaning of `-H' will soon change.  Use `--si' instead.
[4.0.41]
* fix bug in rm introduced in 4.0.38: `chmod 0 f; rm f' would no longer prompt
    before removal.
[4.0.40]
* portability fixes, mainly for UnixWare 7.1.1
[4.0.39]
* cp and mv accept --strip-trailing-slashes, not just --strip-trailing-slash
[4.0.38]
* ls --full-time now implies -l;  before, without -l it was a no-op
[4.0.37]
* portability fixes for SunOS4.1.1, Fujitsu (f300-fujitsu-uxpv4.1_ES),
    and Unicos (alphaev5-cray-unicosmk2.0.5.X)
[4.0.36]
* `mv dir/ new-name' no longer fails on SunOS4.1.1U
* attempting to use mv to move a symlink onto itself no longer removes
    the symlink
* `cp -R directory file' no longer removes `file'.  now it fails and gives
    a diagnostic
* The manual now warns that ls's --full-time format string is planned
    to change in a future release.
* ls -l's time stamp format now depends on LC_TIME, not LC_MESSAGES,
    as POSIX requires.
* ls -l now reports the year for files even slightly in the future, as
    POSIX requires.  This helps warn users about clock skew problems.
* `cp -d file symlink-to-some-other-file' no longer fails
* performance improvements for ls
[4.0.35]
* ln --backup=simple --suffix=SUFFIX once again uses SUFFIX
* install: Likewise.
[4.0.34]
* fix a bug (introduced in 4.0z) that made `chown 123:456 file' act like
    `chown 123:123 file'.  Other uses with a numeric group ID would cause
    chown to fail when it shouldn't have.
* the chown and chgrp programs preserve set-uid and set-gid bits, even on
    systems for which the chown function call resets those bits.
* `ls -L dangling-symlink' now fails (per POSIX) rather than printing the
    link name
* dd no longer honors the just-added `B' suffix on skip= and seek= arguments.
* `mkdir no-such-dir/' no longer fails on NetBSD systems
[4.0.33]
* dd now accepts skip=nB and seek=nB, to advance past some number of bytes, n,
    that need not be a multiple of the block size.
* dd (without conv=notrunc) now complains only when ftruncate fails on a
    regular file, a directory, or a shared memory object -- not when it fails
    to truncate other types of files, like /dev/fd0.
* chmod --changes (-c) once again issues diagnostics only for the files
    with changed permissions
* mkdir now gives one diagnostic (rather than two) for certain failures
* mkdir portability fix for NetBSD
[4.0.32]
* touch now interprets a lone numeric argument of 8 or 10 digits as a file name,
  rather than as a date/time in the obsolescent `MMDDhhmm[YY]' format.
* mkdir no longer sets the permissions of the final directory component
  if it already exists (this bug, too, was introduced recently)
* ls's --full-time format string is now locale dependent
[4.0.31]
* mkdir: fix a bug introduced in 4.0.30 whereby `mkdir existing-dir' would
  succeed.  Now it fails, as it should (and used to).
[4.0.30]
* mkdir: fix a bug introduced in 4.0.28 whereby parent directories created
  via `mkdir -p' would have permissions that did not account for the umask
[4.0.29]
* ls.c wouldn't compile on some systems: fix it
* `cp -R --parents dir1/ dir2' failed on NetBSD, due to a portability problem
[4.0.28]
* ls is much more efficient on systems (e.g., linux-2.4.*) that store file
    type information in directory entries.
* shred now automatically determines the size of each block device argument
* ls's date/time format strings are now locale dependent
* mkdir, mknod, mkfifo, and chmod work better in conjunction with ACLs
* `cp --parents dir1/ dir2' no longer gets a failed assertion
* shred now determines the size of block devices like /dev/fd0
* `shred --exact file1 file2' now erases `file1', too
[4.0.27]
* install once again unlinks an existing destination before trying to open it
* mv no longer gets a failed assertion when moving a directory (specified with
    a trailing slash) from one partition to another, and giving it a different
    name at the destination.
* `cp --link -f src existing-dest' no longer fails (bug introduced in 4.0z)
* cp's new --remove-destination option now works with -R
[4.0z]
* `cp -p' once again preserves `special' permission bits (this bug was
    introduced in 4.0y)
* mv's --force (-f) option now controls solely whether mv prompts (per POSIX)
* `cp -f' now first attempts to open an existing destination file, and only
    if that fails does it resort to unlinking the file and retrying the open.
    Before, it would unlink the file before trying to open it.
* cp accepts a new option, --remove-destination, that provides the old behavior
* cp's -f option no longer cancels the effect of --interactive (-i) (per POSIX)
* when ls sorts directory entries, it now honors the current locale settings
* dd's `skip=BLOCKS' operator once again works on systems with a buggy lseek
  function (Linux, at least on SCSI tape devices)
* fix a typo in install-sh
[4.0y]
* cp now accepts the POSIX-mandated -H and -L options.
* cp -p and mv now try to preserve uid even if you're not root, as per POSIX.2.
  This affects behavior only on hosts that let you give files away via chmod.
* du would fail when given `.' or `..' followed by other command line arguments
* Using cp's short-named `-P' option evokes the warning that the
   meaning of `-P' will soon change.  Use `--parents' instead.
* chgrp, chmod, and chown: when used with the --verbose option, might give an