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Changes in release 2.1
[2.0.22]
* `od -t f8' works once again [bug introduced in textutils-2.0.8]
* various portability fixes, and general clean-up
* various minor, corner-case bug fixes
[2.0.21]
* split accepts new option -a or --suffix-length.
* split no longer generates longer suffixes than requested; instead, it reports
  an error when suffixes are exhausted.  POSIX requires this behavior.
* The _POSIX2_VERSION environment variable lets you select which version
  of POSIX the utilities should conform to.  Its default value is system
  dependent.  Set _POSIX2_VERSION=199209 to cause the utilities to support
  obsolete usage like "sort +1".
* The following obsolete usages are no longer supported when conforming
  to POSIX 1003.1-2001, which prohibits most digit-string options:
    expand -N	(instead, use expand -t N)
    head -N	(instead, use head -c N or head -n N)
    fold -N	(instead, use fold -w N)
    split -N	(instead, use split -l N)
    tail -N	(instead, use tail -c N or tail -n N)
    unexpand -N	(instead, use unexpand --first-only -t N)
    uniq -N	(instead, use uniq -f N)
  The following obsolete usages (options without arguments) are no
  longer supported when conforming to POSIX 1003.1-2001, which
  prohibits most options with optional arguments:
    od -s	(instead, use od --strings)
    od -w	(instead, use od --width)
    pr -S	(instead, use pr --sep-string)
[2.0.20]
* tr no longer gets failed a assertion for [==] or [::]
* The following obsolete usages are no longer supported when conforming
  to POSIX 1003.1-2001, which prohibits most options with leading "+":
    sort +POS1 -POS2	(instead, use sort -k)
    tail +N		(instead, use tail -c +N or tail -n +N)
    uniq +N		(instead, use uniq -s N)
* Warnings are issued for obsolete usages on older hosts,
  unless POSIXLY_CORRECT is set in the environment.
* sort -m no longer segfaults when given an empty file
* sort -S now accepts 'K' as a synonym for 'k'.
* wc recognizes all locale-defined white-space characters, not just those
    in the "C" locale.
[2.0.19]
* portability tweak to make lib/regex.c compile
* split translatable strings only in the middle of sentences
[2.0.18]
* sort could segfault on systems without a working mkstemp function and
    with a gettimeofday function that clobbers the static buffer that
    localtime uses for it's return value -- introduced in 2.0.17
[2.0.17]
* csplit no longer gets a failed assertion for this:
    printf 'a\n\n'|csplit - '/^$/' 2
* sort detects physical memory attributes more portably
* tail no longer gets a segfault on Linux's /proc/ksyms
* sum -s produces the proper 16-bit checksum for large files
    (this fixes a bug that was introduced in 2.0f)
* uniq is now about 3 times faster than the version from 2.0 on Linux systems;
    the code uses lock-avoiding variants of common I/O functions
[2.0.16]
* tail -F no longer segfaults
[2.0.15]
* `head -c N' and `od -N N' now read no more than N bytes of input
* tail accepts new option: -F, equivalent to `--follow=name --retry',
    for compatibility with the FreeBSD and NetBSD versions of tail.
* fmt no longer segfaults when using a maximum line width larger than 32767
* uniq's --all-repeated option has new modes to delimit groups
    of duplicate lines: --all-repeated={precede,separate,none(default)}
[2.0.14]
* sort now accepts long options like "--reverse" and "--".
* sort now checks option syntax as POSIX requires, except that (as usual
  for GNU) options can follow file names unless POSIXLY_CORRECT is set.
  For example, invalid positional combinations like "sort +1 -r -2" are
  now rejected as per POSIX.
* The next POSIX standard will require that obsolescent 'sort'
  positional options like +1 be treated as file names, not options.
  Please use 'sort -k' instead.
[2.0.13]
* pr accepts new -D or --date option, to specify date format.
* The following changes are required by POSIX:
  - If POSIXLY_CORRECT is set, dates in pr headers now look something like
    'Dec  4 23:59 2001', with the exact appearance affected by LC_TIME.
  - pr -h now affects only the center header string, not the entire header.
  - pr no longer truncates headers.
* Spacing in pr headers has been adjusted slightly.
* `fmt --prefix=S' now works when S contains a byte with the high bit set
[2.0.12]
* sort has improved performance when using very little main memory
* sort has improved memory management
* sort is no longer susceptible to certain denial of service attacks
* sort no longer suffers from a race condition whereby an interrupt received
    during cleanup could cause it to fail to remove temporary files.
    This problem could arise only on hosts without sigaction.
[2.0.11]
* sort accepts new -S SIZE option, to specify main-memory usage.
[2.0.10]
* od is faster and more portable than it was in 2.0.9
* tail avoids an uninitialized memory reference
[2.0.9]
* od now prints valid addresses for offsets of 2^32 and larger, and allows
    the byte offset (-j) and byte count (-N) arguments to be 2^32 and larger.
* tail now works with line and byte counts of 2^32 and larger, on systems
    with large file support
* join now works with an 8-bit delimiter
* fix a compilation failure on some Solaris systems with wc.c
[2.0.8]
* od now supports 8-byte integers, assuming they're printable with e.g., %lld
* new program: sha1sum
* wc accepts new -m option: count (potentially multi-byte) characters
* wc's `--chars' option is now equivalent to -m, not --bytes as it used to be
* `cat -n' works properly when processing 2^31 or more lines
[2.0g]
* sort's --help output now warns that it is locale-aware
* tail: fix a buffer underrun error that occurred on an empty pipe,
  also thanks to bounded pointers
* pr: fix a bounds violation found by Greg McGary's bounded-pointers-enabled gcc
  It could have caused (with low probability) the columns on the last page of
  output *not* to be `balanced' when they should have been.
* sort: if the -T tmpdir option is given multiple times, all the given
  directories are used; this can improve performance for huge sort/merges.
[2.0f]
* all programs fail when printing --help or --version output to a full device
* cut no longer gets a segfault under some circumstances
* unexpand accepts new option: --first-only
[2.0e]
* `tail -f directory' no longer gets a failed assertion
* sort: big performance improvement when sorting many small files;
  from Charles Randall
* configure and portability changes in m4/ and lib/
[2.0d]
* preliminary sort performance improvements
* tsort now works more like the traditional UNIX tsort.  Before it would
  exit when it found a loop.  Now it continues and outputs all items.
* unexpand no longer infloops on certain sequences of white space
* unified lib/: now that directory and most of the configuration framework
  is common between fileutils, textutils, and sh-utils
[2.0c]
* include lib/nanosleep.h.
[2.0b]
* portability tweaks for error.c vs. systems with deficient strerror_r
[2.0a]
* `tail --follow=name' no longer gets a failed assertion for a
  dev,inode-reusing race condition
* sort and comm no longer consider newlines to be part of the line,
  as this requirement will likely be removed from POSIX.2.
  This undoes some changes made for textutils 1.22m and 1.22n.
* tail's (short only) -f option no longer accepts an optional argument,
  so e.g., `tail -fn 2 file' works again.
* tail no longer refuses to operate on certain types of files
* fixed bug in tsort's handling of cycles

Changes in release 2.0
[1.22q]
* HPUX portability fix: md5sum would dump core due to use of libc's getline
[1.22p]
* portability fixes from Paul Eggert based largely on tar-1.13 reports
* `tail --pid=PID' now works even when PID belongs to some other user
[1.22o]
* tail accepts new option: --pid=PID
[1.22n]
* tail accepts the following new options (some of which were added in 1.22g):
  --retry
  --follow[={name|descriptor}]
  --max-unchanged-stats=N
  --max-consecutive-size-changes=N
  --sleep-interval=S
* wc uses the POSIX-mandated output format when POSIXLY_CORRECT is set
* To maintain compatibility with sort, comm and join now obey the LC_COLLATE
  locale, and comm now considers newlines to be part of the lines.
* use lib/memchr.c only if it's not provided by the system -- this means
  that on systems with a fast library memchr function you may notice an
  improvement.  If you use a system with a buggy or signifcantly slower
  memchr, please report it.
[1.22m]
* sort now considers newlines to be part of the line, as required by POSIX.2.
  E.g. a line starting with a tab now sorts before an empty line,
  since tab precedes newline in the ASCII collating sequence.
* sort handles NUL bytes correctly when configured/compiled with --enable-nls
* fix typos in my version of AC_SEARCH_LIBS.
* fix dates on config files so builders don't need autoconf/automake
[1.22l]
* sort no longer autodetects the locale of numbers and months,
   as that conflicts with POSIX.2
* `join -tC' now works when input contains trailing spaces
* portability tweaks for Irix's cc
[1.22k]
* `sort -n' works with negative numbers when configured/compiled
   with --enable-nls
* head accepts byte and line counts of type uintmax_t (so up to 2^64 - 1)
[1.22j]
* tail: fix bug introduced in 1.22i
[1.22i]
* tail now terminates in `yes > k & sleep 1; tail -2c k'
* `tail -f' now ensures that stdout is unbuffered
* fix a bug in cut to allow use of 8-bit delimiters
* pr accepts POSIX compliant options -s and -w,
  the new capital letter options -J, -S and _W turn off the
  unexpected interferences of the small letter options -s and -w
  if used together with the column options.
* pr output has been adapted to other UNIXes in some cases.
[1.22h]
* portability tweaks
* Window/NT/DOS support
[1.22g]
* uniq accepts new option: --all-repeated (-D).
* Windows/DOS portability fixes
* new program: tsort
* tail has several new options
* md5sum can handle file names with embedded backslash characters
* pr accepts long option names (see `pr --help')
* new program: ptx (moved to this package from being its own distribution)
[1.22f]
* cut accepts new --output-delimiter=STR option
* `sort -o no-such-file no-such-file' now fails, as it should
* fix pr bug: pr -td didn't double space
* fix tac bug when using -b, -r, and -s SEPARATOR
* fix sort bug whereby using key-local `d' option would cause following
  key specs to be ignored when any two keys (in the `d'-modified test)
  compared equal.
[1.22e]
* remove maintainer mode
[1.22d]
* wc accepts new option: --max-line-length (-L)
* sort can sort according to your locale if your C library supports that
[1.22c]
[1.22b]
* od supports a new trailing `z' character in a type specification:
    $ od -tx1z .
    0000000 be ef c6 0f fd f9 d7 e0 ec cb f3 c6 00 db e8 00  >................<
    0000020 00 00 d2 00 00 00 00 00 00 00 00 00 00 00 00 00  >................<
    0000040 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00  >................<