This file is of historic interest. For recent changes in both ksh 93u+m and
the accompanying libraries, see the file NEWS in the top-level directory.
____

This is a list of changes that have been made since the 12/28/93 version
of ksh.

1.	New features in 12/28/93b
	a.  If IFS contains two consecutive identical characters belonging
	    to the [:space:] class, then this character is treated as
	    a non-space delimiter so that each instance will delimit
	    a field.  For example, IFS=$'\t\t' will cause two consecutive
	    tabs to delimit a null field.
	b.  The getopts command has a -a name option that specifies a
	    name that will be used for usage messages.

2.	New features in 12/28/93e
	a.  The math functions, atan2, hypot, fmod, and pow were added.
	b.  When a shared library is loaded, if the function lib_init()
	    is defined in the library, it is invoked the first time that
	    the library is loaded with builtin -f library.

3.	New features in 12/28/93f
	a.  Hostnames in addition to host addresses can be given in
	    /dev/tcp/host/port virtual file names.
	b.  File name completion and expansion now quotes special
	    characters in file names from both emacs and vi edit modes.

4.	New features in 12/28/93g
	a.  The pipefail option has been added.  With pipefail
	    enabled, a pipeline will not complete until all
	    commands are complete, and the return value will
	    be that of the last command to fail, or zero if
	    all complete successfully.
	b.  When an executable is found on a given path,
	    the appropriate library path variable is prepended
	    with a corresponding library directory.
5.	New features in 12/28/93h
	a.  The PATH search algorithm has been modified to look
	    for a file named .fpath in each bin directory and if
	    found, to search for functions in this directory if
	    it cannot find the command in that directory.
	b.  When performing pathname expansion, the shell checks
	    to see whether each directory it reads is case sensitive
	    or not, and performs the matching accordingly.
	c.  The %T format for printing formatted date/time.
6.	New features in 12/28/93i
	a.  Most of the built-in commands and ksh itself are now
            self documenting.  Running command --man will produce
            screen output.  Running command --html produces the
            man page in html format.
	b.  The getopts builtin can process command description
            strings to produce man pages.

7.	Bugs fixed in 12/28/93a for default OPTIONS
	a.  An expansion bug which causes portions of a word after
	    a $((...)) expansion that contains a nested $var expansion
	    to be lost has been fixed.
	b.  A bug that caused a core dump when a script that did not
	    have PWD set and did a cd inside command substitution
	    has been fixed.
	c.  A bug which caused a core dump on some machines when
	    the LANG variable was assigned to has been fixed.
	d.  A bug which incorrectly handled set disciplines that
	    performed arithmetic evaluation when the discipline
	    was called from the arithmetic evaluator has been fixed.
	e.  A bug caused by an EXIT trap inside a function that
	    was executed in a subshell was fixed.
	f.  If foo is a function, and not a program, then command foo
	    now reports that foo isn't found rather than invoking foo.
	g.  The previous version incorrectly listed -A as an
	    invocation option.  The -A option is only for set.
	h.  A bug was fixed which caused ksh to loop when execution trace
	    was enabled and the PS4 prompt required command substitution.
	i.  A bug which could cause the job control switch character
	    to be disabled when a script that enabled monitor mode
	    terminated was fixed.
	j.  A bug in the macro expansion global replacement operator //,
	    when the pattern began with a [ or +( has been fixed.
	k.  A bug which prevented ~ expansion from occurring when
	    it was terminated with a colon inside an assignment
	    has been fixed.
	l.  A bug in the dot command which prevented autoload functions
	    from working has been fixed.
	m.  A bug which caused a variable to be unset if the
	    its value were expanded inside a set discipline has
	    been fixed.
	n.  Whence -a now longer reports that a defined function
	    is undefined.
	o.  A bug on some systems in which $0 would be incorrect
	    in scripts invoked by name has been fixed.
	p.  Here documents with an empty body now work.
	1.  A bug which disabled argument passing and resetting
	    of options for a script invoked by name inside a
	    function has been fixed.
	r.  A bug in which an EXIT trap set the caller of a function
	    would be executed if a command called inside a function
	    was not found has been fixed.
	s.  A bug which allowed a script to trap signals that are
	    ignored at the time that the shell was invoked has
	    been fixed.
	t.  A bug which caused 2<&1- when applied to a shell built-in
	    to leave standard input closed has been fixed.
	u.  A bug which caused the shell to incorrectly parse
	    $() command substitutions with nested case statements
	    has been fixed.

8.	Bugs fixed in 12/28/93b for default OPTIONS
	a.  A bug which caused unset RANDOM to dump core has been
	    fixed.
	b.  A bug which prevented return for terminating a profile
	    or ENV file has been fixed.
	c.  A bug which prevented standard input from being
	    directed to /dev/null for background jobs when
	    monitor mode was turned off has been fixed.
	d.  Statements of the form typeset -options var[expr]=value
	    did not perform substitutions on expr as expected.
	e.  A bug which prevented the shell from sending a HUP
	    signal to some background jobs that were not disowned
	    has been fixed.
	f.  A bug which allowed a script to trap signals that are
	    ignored at the time that the shell was invoked by exec
	    has been fixed.
	g.  A bug which could cause a core dump when a discipline
	    function was unset within a discipline was fixed.
	h.  The typeset builtin now accepts a first argument of
	    + or - for compatibility with ksh88.
	i.  For compatibility with ksh88, the results of expansions
	    of command arguments will treat the extended character
	    match characters ()|& as ordinary characters.
	j.  A bug which caused read to fail on a file that was
	    open for read/write with <> when the first operation
	    was print or printf has been fixed.
	k.  When a job is suspended, it is put on the top of
	    the job list as required by the POSIX standard.
	l.  The value of OPTARG when an option that required
	    an argument but didn't have one was incorrect in the
	    case the option string began with a :.
	m.  A bug which caused the terminal to get into a bad
	    state with some KEYBD traps in vi-mode has been fixed.
	n.  A bug which caused an invalid trap to cause a script
	    to terminate, rather than just return an error, has
	    been fixed.
	o.  Backreferencing sub-expressions in patterns and replacement
	    strings now works.
	p.  A bug in chmod which caused the -R option to fail has
	    been fixed.

9.	Bugs fixed in 12/28/93c for default OPTIONS
	a.  The expansion of "$@" was incorrect when $1 was the null
	    string.
	b.  A bug which could incorrectly report a syntax error in
	    a backquoted expression when a $ was preceded by \\
	    has been fixed.
	c.  A bug which prevented the shell from exiting after
	    reporting an error when failing to open a script
	    has been fixed.
	d.  A bug that could lead to memory corruption when a
	    large here document that required parameter or command
	    substitution was expanded has been fixed.
	e.  A bug that could cause a core dump on some systems
	    after ksh detected an error when reading a function
	    has been fixed.
	f.  A bug which could cause a coprocess to hang when
	    reading from a process that has terminated has been fixed.
	g.  A bug which caused a script to terminate when set -e
	    was on and the first command of and && or || list
	    failed has been fixed.
	h.  A bug with here documents inside $(...) when the delimiter
	    word is an identifier has been fixed.
	i.  A bug which caused $0 to display the wrong value when
	    a script was invoked as an argument to the . command
	    and the eval command has been fixed.
	j.  A bug that could cause the built-in sleep to hang
	    has been fixed.
	k.  A bug introduces in 12/28/93b which caused the backslash
	    to be removed when it was followed by digit inside double
	    quotes in some instances has been fixed.
	l.  A bug which could cause a core dump if ksh was invoked with
	    standard input closed has been fixed.
	m.  A bug which could cause a core dump if typeset -A was
	    specified for an existing variable has been fixed.
	n.  Variables that were unset but had attributes such as readonly
	    and export were not listed with readonly, export and typeset.
	o.  Several problems with signals have been fixed.
	p.  A bug which prevented ulimit -t from working has been fixed.
	    Also, a bug in which failed ulimits could cause a core dump
	    has also been fixed.
	q.  A bug in expansion of the form ${name/#pattern/string} and
	    ${name/%pattern/string} has been fixed.
	r.  A bug which caused read -r on a line that contained only
	    blanks to get a non-null value has been fixed.
	s.  A bug introduced in the 'a' point release in which
	    ${x='\\'} expanded to \ when x was unset has been fixed.
	t.  A bug which prevented a trap on EXIT from being executed
	    when the last command in a script was a function invocation
	    has been fixed.
	u.  A bug which caused an interactive shell ignore input when
	    standard error was redirected to a file with exec,
	    and then restored with exec 2>&1 has been fixed.
	v.  An interactive shell turns on monitor mode even when
	    standard error has been redirected to a file.
	w.  A bug which could cause standard input to be incorrectly
	    positioned for the last command of a script has been fixed.
	y.  A bug in the edit modes which allowed walking back in
	    the history file for more than HISTSIZE commands has
	    been fixed.
	z.  A bug which could cause a core dump if variable TMPDIR was
	    changed between two command substitutions has been fixed.
	aa. A bug which prevented a trap on EXIT from being cleared
	    has been fixed.

10.	Bugs fixed in 12/28/93d for default OPTIONS
	a.  The \ character was not handled correctly in replacement
	    patterns with ${x/pattern/replace}.
	b.  A bug with read in which the line did not end with
	    a new-line has been fixed.
	c.  A bug in file name generation which sometimes
	    appended a . for filenames that ended in / has
	    been fixed.
	d.  If a process is waited for after a status has
	    been returned by a previous wait, wait now
	    returns 127.
	e.  A bug with hist (fc) -e which prevented a command
	    to re-executed after it had been edited has been fixed.
	f.  A bug which prevented quoting from removing the meaning
	    of unary test operators has been fixed.

11.	Bugs fixed in 12/28/93e for default OPTIONS
	a.  Empty command substitutions of the form $() now work.
	b.  whence -v foo now gives the correct result after calling
	    builtin -d foo.
	c.  A bug in right to left arithmetic assignment for which
	    the arithmetic expression (( y = x = 1.5 )) did not
	    yield 1 for y when x was declared typeset -i was fixed.
	d.  printf has been fixed to handle format containing \0
	    and/or \0145 correctly.  In addition, characters following
	    %b in the format string are no longer displayed when
	    the operand contains \c.
	e.  A bug in printf that could cause the %E format to
	    produce unnormalized results has been fixed.
	f.  A bug which causes some arithmetic expressions to be
	    incorrectly evaluated as integer expressions rather
	    that floating point has been fixed.
	g.  Functions defined inside a subshell no longer remain
	    defined when the subshell completes.
	h.  The error message from sh -c ';echo foo' has been
	    corrected.
	i.  The format for umask -S has been changed to agree
	    with the specification in the POSIX standard.
	j.  A bug that caused side effects in subscript evaluation
	    when tracing was enabled for subscripts using ++ or --
	    has been fixed.
	k.  To conform to the POSIX standard getopts has been changed
	    so that the option char is set to ? when it returns with
	    a non-zero exit status.
	l.  The handling of \} inside ${name...} has been fixed so
	    that the \ quotes the }.
	m.  A bug that caused the read builtin to resume execution
	    after processing a trap has been fixed.
	n.  [[ -s file ]] has been fixed so that if file is open
	    by ksh, it is flushed first.
	o.  In some cases attributes and sizes for non exported
	    variables weren't being reset before running a script.
	p.  The value of TMOUT was affected by changes make to
	    it in a subshell.
	q.  The jobs command did not reflect changes make by
	    sending the CONT signal to a command.
	r.  The error message for ksh -o unknown was incorrect.
	s.  Functions invoked as name=value name, did not use
	    values from the calling scope when evaluating value.
	t.  A bug in which the shell would re-execute previously
	    executed code when a shell script or coprocess was
	    run in the background has been fixed.
	u.  A bug in which an empty here-document would leave
	    a file descriptor open has been fixed.
	v.  A bug in which $(set -A array ...) would leave a
	    side effect has been fixed.
	w.  A discipline function for a global variable defined
	    within a function defined with the function keyword,
	    incorrectly created a local variable of the same name
	    and applied the discipline to it.

12.	Bugs fixed in 12/28/93f for default OPTIONS
	a.  A bug which would cause the secondary prompt to be
	    displayed when a user entered a literal carriage
	    return has been fixed.
	b.  I bug which caused ksh read -s name to core dump was
	    fixed.
	c.  I bug with the expansion of \} and \] inside double
	    quoted strings that also contained variable expansions
	    has been fixed
	d.  Changes in the 'e' point release caused autoload
	    functions invoked from within command substitution
	    to fail.  This has been fixed.
	e.  A bug in the processing of here-documents that could
	    prevent variable substitution to occur after $(...) command
	    substitution for long here documents has been fixed.
	f.  A bug caused by a race condition that could cause SIGTERM
	    to be ignored by a child process has been fixed.
	g.  A bug which prevented the startup of a coprocess immediately
	    after killing a running coprocess has been fixed.
	h.  ulimit foobar, where foobar is not an arithmetic
	    expression, now gives an error message as it did with ksh88
	    instead of setting the file size limit to 0.
	i.  A bug which could cause an interactive shell to terminate when
	    the last process of a pipeline was a POSIX function was fixed.
	j.  A bug which could cause command substitution of a shell script
	    to core dump has been fixed.
	k.  A security hole was fixed in suid_exec.
	l.  Arithmetic functions such as pow() that take more than
	    one argument, did not work if arguments other than the
	    first contained parenthesized sub-expression.
	m.  The error message from a script containing an incomplete
	    arithmetic expression has been corrected.
	n.  A bug which caused a core dump on some machines when
	    the value of a name reference contained a positional
	    parameter and the name reference was not defined inside
	    a function has been fixed.
	o.  Arithmetic expressions now correctly handle hexadecimal
	    constants.
	p.  A bug in which integer variables could be expanded
	    with a leading 10# when declared with typeset -i
	    multiple times has been corrected.
	q.  A bug in which IFS wasn't correctly restored when
	    set within command substitution has been fixed.
	r.  The _ character is now considered as part of a word
	    with the M-f and M-b emacs directives as it was in ksh88.

13.	Bugs fixed in 12/28/93g for default OPTIONS
	a.  A bug in which a name reference could be created to
	    itself and later cause the shell to get into an infinite
	    loop has been fixed.
	b.  A bug in shcomp relating to compound variables was fixed.
	c.  A bug introduced in 'e' in which leading 0's in -Z
	    fields caused the value to be treated as octal for arithmetic
	    evaluation has been fixed.
	d.  A bug when a name reference with a shorter name than
            the variable it references was the subject of a compound
	    assignment has been fixed.
	e.  A bug which in which assignment to array variables in
	    a subshell could affect the parent shell has been
	    fixed.
	f.  read name?prompt was putting a 0 byte at the end of the
	    prompt on standard error.
	g.  A bug in [[ string1 > string2 ]] when ksh was run with -x
	    has been fixed.
	k.  A bug in which the escape character was not processed
	    correctly inside {...} when brace expansion is enabled
	    has been fixed, for example {\$foo}.
	l.  A bug in line continuation in here-documents has been
	    fixed.
	m.  The default base when not specified with typeset -i is
	    10 in accordance with the documentation.  Previously,
	    the value was determined by the first assignment.
	n.  A parsing bug in which a # preceded alphanumeric
	    characters inside a command substitution caused
	    a syntax error to be reported has been fixed.
	o.  A bug in which a decimal constant represented as 10#ddd
	    where ddd was more than five digits generated a syntax
	    error has been fixed.
	p.  A bug in here document expansion in which ${...} expansions
	    were split across buffer boundaries has been fixed.

14.	Bugs fixed in 12/28/93h for default OPTIONS
	a.  I bug in shcomp for compilation of unary operators with [[ ... ]]
	    has been fixed.
	b.  A bug in which the value of $? was changed when executing
	    a keyboard trap has been fixed.
	c.  The handling of SIGCHLD has been changed so that the
	    trap is not triggered while executing trap commands
	    to avoid recursive trap calls.
	d.  I bug in which a local variable in a function declared readonly
	    would generated an error when the function went out of
	    scope has been fixed.
	e.  I bug in which \<new_line> entered from the keyboard
	    with the KEYBD trap enabled has been fixed.
	f.  The error message for a misplaced ((, for example print ((3),
	    was often garbled and has been fixed.
	g.  I bug in the KEYBD trap in which escape sequences of the form
	    <ESC>[#~ were not being handled as a unit has been fixed.
	h.  A bug in which ksh would consider expressions like [[ (a) ]]
	    as syntax errors has been fixed.
	i.  A function defined as foo() without a function body
	    was not reported as a syntax error.
	j.  A bug in which ksh could run out of file descriptors when
	    a stream was repeatedly opened with exec and read from
	    has been fixed.
	k.  A bug introduced when fixing item n from the 'g' point
	    release has been fixed.

15.	Bugs fixed in 12/28/93i for default OPTIONS
        a.  A bug in which a script could terminate when getopts
            encountered an error when invoked inside a function
            has been fixed.
        b.  When a symbolic link was specified as the name of
            the script to invoke by name, the value of $0 was
            set to the real file name rather than the link name
            in some cases and this has been fixed.

16.	Bug fixes for specific non-default option combinations.
	a.  More signal names have been added for Solaris
	b.  A bug fixed for the v directive in vi MULTIBYTE has been
	    fixed.
	c.  Code to for IFS handling of multibyte characters has
	    been added.
	d.  The displaying of multibyte strings in export, readonly,
	    typeset, and execution traces has been fixed.
	e.  A bug with type ahead and KEYBOARD traps with the
	    MULTIBYTE option set has been fixed.
	f.  The k-shell information abstraction database option, KIA,
	    has been revamped for the 'e' point release.
	g.  A bug in brace pattern expansions that caused expressions
	    such as {foo\,bar,bam} to expand incorrectly have been fixed.
	h.  On the U/WIN version for Window 95 and Windows NT,
	    when a directory beginning with a letter followed by
	    a colon is given to cd, it is assumed to be an absolute
	    directory.
	i.  There was a bug in the compile option that does not
	    use fork() in which the current option settings where
	    not propagated to subshells.
	j.  A bug in setting .sh.editchar during the KEYBD trap
	    for the MULTIBYTE option was fixed in release 'h'.
	k.  A bug in which the precision given as an argument
	    to printf was not working has been fixed.

17.	Other changes to 12/28/93[abcdefghi]
	a.  A couple of minor changes to make adding built-ins easier.
	b.  Variables inside functions are now statically scoped.
	    The previous behavior was never documented.
	c.  A few changes have been made to the name-value library
	    that affect built-ins that use disciplines.  The
	    changes allow disciplines to be shared by variables
	    and should make it possible to add new disciplines
	    without recompilation.
	d.  The name-value library interface has undergone significant
	    change for this revision.  See the new nval.3 man page.
	e.  Builtin functions can take a third argument which is
	    a void*.
	f.  The nv_scan() function can restrict the scope of a walk
	    to the top scope.  Starting in 'f', nv_scan() has an
	    additional pointer argument that is passed to each invoked
	    function.
	g.  Starting with release 'f', an empty for list behave like
	    a for list with null expansions.  It produces a warning
	    message with sh -n.
	h.  Starting with release 'f' the code has been modified to
	    work with EBCDIC as well as ASCII.
	i.  Starting with the release 'g', the name-value pair library
	    uses the cdt library rather than the hash library.
	j.  The sh_fun() function now takes third argument which
	    is an argument list for the invoked discipline function
	    or built-in.
	k.  A callback function can be installed which will give
	    notification of file duplications and file closes.

18.	Incompatibilities with 12/28/93 version.
	None intentional.
