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****************************************************************/

This file lists all bug fixes, changes, etc., made since the AWK book

was sent to the printers in August, 1987.

Oct 25, 2018:

	Added test in maketab.c to prevent generating a proctab entry

	for YYSTYPE_IS_DEFINED.  It was harmless but some gcc settings

	generated a warning message.  Thanks to Nan Xiao for report.

Aug 27, 2018:

	Disallow '$' in printf formats; arguments evaluated in order

	and printed in order.

	Added some casts to silence warnings on debugging printfs.

	(Thanks, Arnold.)

Aug 23, 2018:

        A long list of fixes courtesy of Arnold Robbins,

        to whom profound thanks.

        1. ofs-rebuild: OFS value used to rebuild the record was incorrect.

        Fixed August 19, 2014. Revised fix August 2018.

        2. system-status: Instead of a floating-point division by 256, use

        the wait(2) macros to create a reasonable exit status.

        Fixed March 12, 2016.

        3. space: Use provided xisblank() function instead of ispace() for

        matching [[:blank:]].

        4. a-format: Add POSIX standard %a and %A to supported formats. Check

        at runtime that this format is available.

        5. decr-NF: Decrementing NF did not change $0. This is a decades-old

        bug. There are interactions with the old and new value of OFS as well.

        Most of the fix came from the NetBSD awk.

        6. string-conv: String conversions of scalars were sticky.  Once a

        conversion to string happened, even with OFMT, that value was used until

        a new numeric value was assigned, even if OFMT differed from CONVFMT,

        and also if CONVFMT changed.

        7. unary-plus: Unary plus on a string constant returned the string.

        Instead, it should convert the value to numeric and give that value.

	Also added Arnold's tests for these to awktest.tar as T.arnold.

Aug 15, 2018:

	fixed mangled awktest.tar (thanks, Arnold), posted all

	current (very minor) fixes to github / onetrueawk

Jun 7, 2018:

	(yes, a long layoff)

	Updated some broken tests (beebe.tar, T.lilly)

	[thanks to Arnold Robbins]

Mar 26, 2015:

	buffer overflow in error reporting; thanks to tobias ulmer

	and john-mark gurney for spotting it and the fix.

Feb 4, 2013:

	cleaned up a handful of tests that didn't seem to actually

	test for correct behavior: T.latin1, T.gawk.

Jan 5, 2013:

	added ,NULL initializer to static Cells in run.c; not really

	needed but cleaner.  Thanks to Michael Bombardieri.

Dec 20, 2012:

	fiddled makefile to get correct yacc and bison flags.  pick yacc

	(linux) or bison (mac) as necessary.

	added  __attribute__((__noreturn__)) to a couple of lines in

	proto.h, to silence someone's enthusiastic checker.

	fixed obscure call by value bug in split(a[1],a) reported on

	9fans.  the management of temporary values is just a mess; i

	took a shortcut by making an extra string copy.  thanks

	to paul patience and arnold robbins for passing it on and for

	proposed patches.

	tiny fiddle in setfval to eliminate -0 results in T.expr, which

	has irritated me for 20+ years.

Aug 10, 2011:

	another fix to avoid core dump with delete(ARGV); again, many thanks

	to ruslan ermilov.

Aug 7, 2011:

	split(s, a, //) now behaves the same as split(s, a, "")

Jun 12, 2011:

	/pat/, \n /pat/ {...} is now legal, though bad style to use.

	added checks to new -v code that permits -vnospace; thanks to

	ruslan ermilov for spotting this and providing the patch. 

	removed fixed limit on number of open files; thanks to aleksey

	cheusov and christos zoulos. 

	fixed day 1 bug that resurrected deleted elements of ARGV when

	used as filenames (in lib.c).

	minor type fiddles to make gcc -Wall -pedantic happier (but not

	totally so); turned on -fno-strict-aliasing in makefile.

May 6, 2011:

	added #ifdef for isblank.

	now allows -ffoo as well as -f foo arguments.

	(thanks, ruslan)

May 1, 2011:

	after advice from todd miller, kevin lo, ruslan ermilov,

	and arnold robbins, changed srand() to return the previous

	seed (which is 1 on the first call of srand).  the seed is

	an Awkfloat internally though converted to unsigned int to

	pass to the library srand().  thanks, everyone. 

	fixed a subtle (and i hope low-probability) overflow error

	in fldbld, by adding space for one extra \0.  thanks to 

	robert bassett for spotting this one and providing a fix.

	removed the files related to compilation on windows.  i no

	longer have anything like a current windows environment, so

	i can't test any of it.

May 23, 2010:

	fixed long-standing overflow bug in run.c; many thanks to

	nelson beebe for spotting it and providing the fix.

	fixed bug that didn't parse -vd=1 properly; thanks to santiago

	vila for spotting it.

Feb 8, 2010:

	i give up.  replaced isblank with isspace in b.c; there are

	no consistent header files.

Nov 26, 2009:

	fixed a long-standing issue with when FS takes effect.  a

	change to FS is now noticed immediately for subsequent splits.

	changed the name getline() to awkgetline() to avoid yet another

	name conflict somewhere.

Feb 11, 2009:

	temporarily for now defined HAS_ISBLANK, since that seems to

	be the best way through the thicket.  isblank arrived in C99,

	but seems to be arriving at different systems at different

	times.

Oct 8, 2008:

	fixed typo in b.c that set tmpvec wrongly.  no one had ever

	run into the problem, apparently.  thanks to alistair crooks.

Oct 23, 2007:

	minor fix in lib.c: increase inputFS to 100, change malloc

	for fields to n+1.  

	fixed memory fault caused by out of order test in setsval.

	thanks to david o'brien, freebsd, for both fixes.

May 1, 2007:

	fiddle in makefile to fix for BSD make; thanks to igor sobrado.

Mar 31, 2007:

	fixed some null pointer refs calling adjbuf.

Feb 21, 2007:

	fixed a bug in matching the null RE in sub and gsub.  thanks to al aho

	who actually did the fix (in b.c), and to wolfgang seeberg for finding

	it and providing a very compact test case.

	fixed quotation in b.c; thanks to Hal Pratt and the Princeton Dante

	Project.

	removed some no-effect asserts in run.c.

	fiddled maketab.c to not complain about bison-generated values.

	removed the obsolete -V argument; fixed --version to print the

	version and exit.

	fixed wording and an outright error in the usage message; thanks to igor

	sobrado and jason mcintyre.

	fixed a bug in -d that caused core dump if no program followed.

Jan 1, 2007:

	dropped mac.code from makefile; there are few non-MacOSX

	mac's these days.

Jan 17, 2006:

	system() not flagged as unsafe in the unadvertised -safe option.

	found it while enhancing tests before shipping the ;login: article.

	practice what you preach.

	removed the 9-years-obsolete -mr and -mf flags.

	added -version and --version options.

	core dump on linux with BEGIN {nextfile}, now fixed.

	removed some #ifdef's in run.c and lex.c that appear to no 

	longer be necessary.

Apr 24, 2005:

	modified lib.c so that values of $0 et al are preserved in the END

	block, apparently as required by posix.  thanks to havard eidnes

	for the report and code.

Jan 14, 2005:

	fixed infinite loop in parsing, originally found by brian tsang.

	thanks to arnold robbins for a suggestion that started me

	rethinking it.

Dec 31, 2004:

	prevent overflow of -f array in main, head off potential error in 

	call of SYNTAX(), test malloc return in lib.c, all with thanks to 

	todd miller.

Dec 22, 2004:

	cranked up size of NCHARS; coverity thinks it can be overrun with

	smaller size, and i think that's right.  added some assertions to b.c

	to catch places where it might overrun.  the RE code is still fragile.

Dec 5, 2004:

	fixed a couple of overflow problems with ridiculous field numbers:

	e.g., print $(2^32-1).  thanks to ruslan ermilov, giorgos keramidas

	and david o'brien at freebsd.org for patches.  this really should

	be re-done from scratch.

Nov 21, 2004:

	fixed another 25-year-old RE bug, in split.  it's another failure

	to (re-)initialize.  thanks to steve fisher for spotting this and

	providing a good test case.

Nov 22, 2003:

	fixed a bug in regular expressions that dates (so help me) from 1977;

	it's been there from the beginning.  an anchored longest match that

	was longer than the number of states triggered a failure to initialize

	the machine properly.  many thanks to moinak ghosh for not only finding

	this one but for providing a fix, in some of the most mysterious

	code known to man.

	fixed a storage leak in call() that appears to have been there since

	1983 or so -- a function without an explicit return that assigns a 

	string to a parameter leaked a Cell.  thanks to moinak ghosh for 

	spotting this very subtle one.

Jul 31, 2003:

	fixed, thanks to andrey chernov and ruslan ermilov, a bug in lex.c

	that mis-handled the character 255 in input.  (it was being compared

	to EOF with a signed comparison.)

Jul 29, 2003:

	fixed (i think) the long-standing botch that included the beginning of

	line state ^ for RE's in the set of valid characters; this led to a

	variety of odd problems, including failure to properly match certain

	regular expressions in non-US locales.  thanks to ruslan for keeping

	at this one.

Jul 28, 2003:

	n-th try at getting internationalization right, with thanks to volker

	kiefel, arnold robbins and ruslan ermilov for advice, though they

	should not be blamed for the outcome.  according to posix, "."  is the

	radix character in programs and command line arguments regardless of

	the locale; otherwise, the locale should prevail for input and output

	of numbers.  so it's intended to work that way.

	i have rescinded the attempt to use strcoll in expanding shorthands in

	regular expressions (cclenter).  its properties are much too

	surprising; for example [a-c] matches aAbBc in locale en_US but abBcC

	in locale fr_CA.  i can see how this might arise by implementation

	but i cannot explain it to a human user.  (this behavior can be seen

	in gawk as well; we're leaning on the same library.)

	the issue appears to be that strcoll is meant for sorting, where

	merging upper and lower case may make sense (though note that unix

	sort does not do this by default either).  it is not appropriate

	for regular expressions, where the goal is to match specific

	patterns of characters.  in any case, the notations [:lower:], etc.,

	are available in awk, and they are more likely to work correctly in

	most locales.

	a moratorium is hereby declared on internationalization changes.

	i apologize to friends and colleagues in other parts of the world.

	i would truly like to get this "right", but i don't know what

	that is, and i do not want to keep making changes until it's clear.

Jul 4, 2003:

	fixed bug that permitted non-terminated RE, as in "awk /x".

Jun 1, 2003:

	subtle change to split: if source is empty, number of elems

	is always 0 and the array is not set.

Mar 21, 2003:

	added some parens to isblank, in another attempt to make things

	internationally portable.

Mar 14, 2003:

	the internationalization changes, somewhat modified, are now

	reinstated.  in theory awk will now do character comparisons

	and case conversions in national language, but "." will always

	be the decimal point separator on input and output regardless

	of national language.  isblank(){} has an #ifndef.

	this no longer compiles on windows: LC_MESSAGES isn't defined

	in vc6++.

	fixed subtle behavior in field and record splitting: if FS is

	a single character and RS is not empty, \n is NOT a separator.

	this tortuous reading is found in the awk book; behavior now

	matches gawk and mawk.

Dec 13, 2002:

	for the moment, the internationalization changes of nov 29 are

	rolled back -- programs like x = 1.2 don't work in some locales,

	because the parser is expecting x = 1,2.  until i understand this

	better, this will have to wait.

Nov 29, 2002:

	modified b.c (with tiny changes in main and run) to support

	locales, using strcoll and iswhatever tests for posix character

	classes.  thanks to ruslan ermilov (ru@freebsd.org) for code.

	the function isblank doesn't seem to have propagated to any

	header file near me, so it's there explicitly.  not properly

	tested on non-ascii character sets by me.

Jun 28, 2002:

	modified run/format() and tran/getsval() to do a slightly better

	job on using OFMT for output from print and CONVFMT for other

	number->string conversions, as promised by posix and done by 

	gawk and mawk.  there are still places where it doesn't work

	right if CONVFMT is changed; by then the STR attribute of the

	variable has been irrevocably set.  thanks to arnold robbins for

	code and examples.

	fixed subtle bug in format that could get core dump.  thanks to

	Jaromir Dolecek <jdolecek@NetBSD.org> for finding and fixing.

	minor cleanup in run.c / format() at the same time.

	added some tests for null pointers to debugging printf's, which

	were never intended for external consumption.  thanks to dave

	kerns (dkerns@lucent.com) for pointing this out.

	GNU compatibility: an empty regexp matches anything (thanks to

	dag-erling smorgrav, des@ofug.org).  subject to reversion if

	this does more harm than good.

	pervasive small changes to make things more const-correct, as

	reported by gcc's -Wwrite-strings.  as it says in the gcc manual,

	this may be more nuisance than useful.  provoked by a suggestion

	and code from arnaud desitter, arnaud@nimbus.geog.ox.ac.uk

	minor documentation changes to note that this now compiles out

	of the box on Mac OS X.

Feb 10, 2002:

	changed types in posix chars structure to quiet solaris cc.

Jan 1, 2002:

	fflush() or fflush("") flushes all files and pipes.

	length(arrayname) returns number of elements; thanks to 

	arnold robbins for suggestion.

	added a makefile.win to make it easier to build on windows.

	based on dan allen's buildwin.bat.

Nov 16, 2001:

	added support for posix character class names like [:digit:],

	which are not exactly shorter than [0-9] and perhaps no more

	portable.  thanks to dag-erling smorgrav for code.

Feb 16, 2001:

	removed -m option; no longer needed, and it was actually

	broken (noted thanks to volker kiefel).

Feb 10, 2001:

	fixed an appalling bug in gettok: any sequence of digits, +,-, E, e,

	and period was accepted as a valid number if it started with a period.

	this would never have happened with the lex version.

	other 1-character botches, now fixed, include a bare $ and a

	bare " at the end of the input.

Feb 7, 2001:

	more (const char *) casts in b.c and tran.c to silence warnings.

Nov 15, 2000:

	fixed a bug introduced in august 1997 that caused expressions

	like $f[1] to be syntax errors.  thanks to arnold robbins for

	noticing this and providing a fix.

Oct 30, 2000:

	fixed some nextfile bugs: not handling all cases.  thanks to

	arnold robbins for pointing this out.  new regressions added.

	close() is now a function.  it returns whatever the library

	fclose returns, and -1 for closing a file or pipe that wasn't

	opened.

Sep 24, 2000:

	permit \n explicitly in character classes; won't work right

	if comes in as "[\n]" but ok as /[\n]/, because of multiple

	processing of \'s.  thanks to arnold robbins.

July 5, 2000:

	minor fiddles in tran.c to keep compilers happy about uschar.

	thanks to norman wilson.

May 25, 2000:

	yet another attempt at making 8-bit input work, with another

	band-aid in b.c (member()), and some (uschar) casts to head 

	off potential errors in subscripts (like isdigit).  also

	changed HAT to NCHARS-2.  thanks again to santiago vila.

	changed maketab.c to ignore apparently out of range definitions

	instead of halting; new freeBSD generates one.  thanks to

	jon snader <jsnader@ix.netcom.com> for pointing out the problem.

May 2, 2000:

	fixed an 8-bit problem in b.c by making several char*'s into

	unsigned char*'s.  not clear i have them all yet.  thanks to

	Santiago Vila <sanvila@unex.es> for the bug report.

Apr 21, 2000:

	finally found and fixed a memory leak in function call; it's

	been there since functions were added ~1983.  thanks to

	jon bentley for the test case that found it.

	added test in envinit to catch environment "variables" with

	names beginning with '='; thanks to Berend Hasselman.

Jul 28, 1999:

	added test in defn() to catch function foo(foo), which

	otherwise recurses until core dump.  thanks to arnold

	robbins for noticing this.

Jun 20, 1999:

	added *bp in gettok in lex.c; appears possible to exit function

	without terminating the string.  thanks to russ cox.

Jun 2, 1999:

	added function stdinit() to run to initialize files[] array,

	in case stdin, etc., are not constants; some compilers care.

May 10, 1999:

	replaced the ERROR ... FATAL, etc., macros with functions

	based on vprintf, to avoid problems caused by overrunning

	fixed-size errbuf array.  thanks to ralph corderoy for the

	impetus, and for pointing out a string termination bug in

	qstring as well.

Apr 21, 1999:

	fixed bug that caused occasional core dumps with commandline

	variable with value ending in \.  (thanks to nelson beebe for

	the test case.)

Apr 16, 1999:

	with code kindly provided by Bruce Lilly, awk now parses 

	/=/ and similar constructs more sensibly in more places.

	Bruce also provided some helpful test cases.

Apr 5, 1999:

	changed true/false to True/False in run.c to make it

	easier to compile with C++.  Added some casts on malloc

	and realloc to be honest about casts; ditto.  changed

	ltype int to long in struct rrow to reduce some 64-bit

	complaints; other changes scattered throughout for the

	same purpose.  thanks to Nelson Beebe for these portability

	improvements.

	removed some horrible pointer-int casting in b.c and elsewhere

	by adding ptoi and itonp to localize the casts, which are

	all benign.  fixed one incipient bug that showed up on sgi

	in 64-bit mode.

	reset lineno for new source file; include filename in error

	message.  also fixed line number error in continuation lines.

	(thanks to Nelson Beebe for both of these.)

Mar 24, 1999:

	Nelson Beebe notes that irix 5.3 yacc dies with a bogus

	error; use a newer version or switch to bison, since sgi

	is unlikely to fix it.

Mar 5, 1999:

	changed isnumber to is_number to avoid the problem caused by

	versions of ctype.h that include the name isnumber.

	distribution now includes a script for building on a Mac,

	thanks to Dan Allen.

Feb 20, 1999:

	fixed memory leaks in run.c (call) and tran.c (setfval).

	thanks to Stephen Nutt for finding these and providing the fixes.

Jan 13, 1999:

	replaced srand argument by (unsigned int) in run.c;

	avoids problem on Mac and potentially on Unix & Windows.

	thanks to Dan Allen.

	added a few (int) casts to silence useless compiler warnings.

	e.g., errorflag= in run.c jump().

	added proctab.c to the bundle outout; one less thing

	to have to compile out of the box.

	added calls to _popen and _pclose to the win95 stub for

	pipes (thanks to Steve Adams for this helpful suggestion).

	seems to work, though properties are not well understood

	by me, and it appears that under some circumstances the

	pipe output is truncated.  Be careful.

Oct 19, 1998:

	fixed a couple of bugs in getrec: could fail to update $0

	after a getline var; because inputFS wasn't initialized, 

	could split $0 on every character, a misleading diversion.

	fixed caching bug in makedfa: LRU was actually removing

	least often used.

	thanks to ross ridge for finding these, and for providing

	great bug reports.

May 12, 1998:

	fixed potential bug in readrec: might fail to update record

	pointer after growing.  thanks to dan levy for spotting this

	and suggesting the fix.

Mar 12, 1998:

	added -V to print version number and die.

[notify dave kerns, dkerns@dacsoup.ih.lucent.com]

Feb 11, 1998:

	subtle silent bug in lex.c: if the program ended with a number

	longer than 1 digit, part of the input would be pushed back and

	parsed again because token buffer wasn't terminated right.

	example:  awk 'length($0) > 10'.  blush.  at least i found it

	myself.

Aug 31, 1997:

	s/adelete/awkdelete/: SGI uses this in malloc.h.

	thanks to nelson beebe for pointing this one out.

Aug 21, 1997:

	fixed some bugs in sub and gsub when replacement includes \\.

	this is a dark, horrible corner, but at least now i believe that

	the behavior is the same as gawk and the intended posix standard.

	thanks to arnold robbins for advice here.

Aug 9, 1997:

	somewhat regretfully, replaced the ancient lex-based lexical

	analyzer with one written in C.  it's longer, generates less code,

	and more portable; the old one depended too much on mysterious

	properties of lex that were not preserved in other environments.

	in theory these recognize the same language.

	now using strtod to test whether a string is a number, instead of

	the convoluted original function.  should be more portable and

	reliable if strtod is implemented right.

	removed now-pointless optimization in makefile that tries to avoid

	recompilation when awkgram.y is changed but symbols are not.

	removed most fixed-size arrays, though a handful remain, some

	of which are unchecked.  you have been warned.

Aug 4, 1997:

	with some trepidation, replaced the ancient code that managed

	fields and $0 in fixed-size arrays with arrays that grow on

	demand.  there is still some tension between trying to make this

	run fast and making it clean; not sure it's right yet.

	the ill-conceived -mr and -mf arguments are now useful only

	for debugging.  previous dynamic string code removed.

	numerous other minor cleanups along the way.

Jul 30, 1997:

	using code provided by dan levy (to whom profuse thanks), replaced

	fixed-size arrays and awkward kludges by a fairly uniform mechanism

	to grow arrays as needed for printf, sub, gsub, etc.

Jul 23, 1997:

	falling off the end of a function returns "" and 0, not 0.

	thanks to arnold robbins.

Jun 17, 1997:

	replaced several fixed-size arrays by dynamically-created ones

	in run.c; added overflow tests to some previously unchecked cases.

	getline, toupper, tolower.

	getline code is still broken in that recursive calls may wind

	up using the same space.  [fixed later]

	increased RECSIZE to 8192 to push problems further over the horizon.

	added \r to \n as input line separator for programs, not data.

	damn CRLFs.

	modified format() to permit explicit printf("%c", 0) to include

	a null byte in output.  thanks to ken stailey for the fix.

	added a "-safe" argument that disables file output (print >,

	print >>), process creation (cmd|getline, print |, system), and

	access to the environment (ENVIRON).  this is a first approximation

	to a "safe" version of awk, but don't rely on it too much.  thanks

	to joan feigenbaum and matt blaze for the inspiration long ago.

Jul 8, 1996:

	fixed long-standing bug in sub, gsub(/a/, "\\\\&"); thanks to

	ralph corderoy.

Jun 29, 1996:

	fixed awful bug in new field splitting; didn't get all the places

	where input was done.

Jun 28, 1996:

	changed field-splitting to conform to posix definition: fields are

	split using the value of FS at the time of input; it used to be

	the value when the field or NF was first referred to, a much less

	predictable definition.  thanks to arnold robbins for encouragement

	to do the right thing.

May 28, 1996:

	fixed appalling but apparently unimportant bug in parsing octal

	numbers in reg exprs.

	explicit hex in reg exprs now limited to 2 chars: \xa, \xaa.

May 27, 1996:

	cleaned up some declarations so gcc -Wall is now almost silent.

	makefile now includes backup copies of ytab.c and lexyy.c in case

	one makes before looking; it also avoids recreating lexyy.c unless

	really needed.

	s/aprintf/awkprint, s/asprintf/awksprintf/ to avoid some name clashes

	with unwisely-written header files.

	thanks to jeffrey friedl for several of these.

May 26, 1996:

	an attempt to rationalize the (unsigned) char issue.  almost all

	instances of unsigned char have been removed; the handful of places

	in b.c where chars are used as table indices have been hand-crafted.

	added some latin-1 tests to the regression, but i'm not confident;

	none of my compilers seem to care much.  thanks to nelson beebe for

	pointing out some others that do care.

May 2, 1996:

	removed all register declarations.

	enhanced split(), as in gawk, etc:  split(s, a, "") splits s into

	a[1]...a[length(s)] with each character a single element.

	made the same changes for field-splitting if FS is "".

	added nextfile, as in gawk: causes immediate advance to next

	input file. (thanks to arnold robbins for inspiration and code).

	small fixes to regexpr code:  can now handle []], [[], and

	variants;  [] is now a syntax error, rather than matching 

	everything;  [z-a] is now empty, not z.  far from complete

	or correct, however.  (thanks to jeffrey friedl for pointing out

	some awful behaviors.)

Apr 29, 1996:

	replaced uchar by uschar everywhere; apparently some compilers

	usurp this name and this causes conflicts.

	fixed call to time in run.c (bltin); arg is time_t *.

	replaced horrible pointer/long punning in b.c by a legitimate

	union.  should be safer on 64-bit machines and cleaner everywhere.

	(thanks to nelson beebe for pointing out some of these problems.)

	replaced nested comments by #if 0...#endif in run.c, lib.c.

	removed getsval, setsval, execute macros from run.c and lib.c.

	machines are 100x faster than they were when these macros were

	first used.

	revised filenames: awk.g.y => awkgram.y, awk.lx.l => awklex.l,

	y.tab.[ch] => ytab.[ch], lex.yy.c => lexyy.c, all in the aid of

	portability to nameless systems.

	"make bundle" now includes yacc and lex output files for recipients

	who don't have yacc or lex.

Aug 15, 1995:

	initialized Cells in setsymtab more carefully; some fields

	were not set.  (thanks to purify, all of whose complaints i

	think i now understand.)

	fixed at least one error in gsub that looked at -1-th element

	of an array when substituting for a null match (e.g., $).

	delete arrayname is now legal; it clears the elements but leaves

	the array, which may not be the right behavior.

	modified makefile: my current make can't cope with the test used

	to avoid unnecessary yacc invocations.

Jul 17, 1995:

	added dynamically growing strings to awk.lx.l and b.c

	to permit regular expressions to be much bigger.

	the state arrays can still overflow.

Aug 24, 1994:

	detect duplicate arguments in function definitions (mdm).

May 11, 1994:

	trivial fix to printf to limit string size in sub().

Apr 22, 1994:

	fixed yet another subtle self-assignment problem:

	$1 = $2; $1 = $1 clobbered $1.

	Regression tests now use private echo, to avoid quoting problems.

Feb 2, 1994:

	changed error() to print line number as %d, not %g.

Jul 23, 1993:

	cosmetic changes: increased sizes of some arrays,

	reworded some error messages.

	added CONVFMT as in posix (just replaced OFMT in getsval)

	FILENAME is now "" until the first thing that causes a file

	to be opened.

Nov 28, 1992:

	deleted yyunput and yyoutput from proto.h;

	different versions of lex give these different declarations.

May 31, 1992:

	added -mr N and -mf N options: more record and fields.

	these really ought to adjust automatically.

	cleaned up some error messages; "out of space" now means

	malloc returned NULL in all cases.

	changed rehash so that if it runs out, it just returns;

	things will continue to run slow, but maybe a bit longer.

Apr 24, 1992:

	remove redundant close of stdin when using -f -.

	got rid of core dump with -d; awk -d just prints date.

Apr 12, 1992:

	added explicit check for /dev/std(in,out,err) in redirection.

	unlike gawk, no /dev/fd/n yet.

	added (file/pipe) builtin.  hard to test satisfactorily.

	not posix.

Feb 20, 1992:

	recompile after abortive changes;  should be unchanged.

Dec 2, 1991:

	die-casting time:  converted to ansi C, installed that.

Nov 30, 1991:

	fixed storage leak in freefa, failing to recover [N]CCL.

	thanks to Bill Jones (jones@cs.usask.ca)

Nov 19, 1991:

	use RAND_MAX instead of literal in builtin().

Nov 12, 1991:

	cranked up some fixed-size arrays in b.c, and added a test for

	overflow in penter.  thanks to mark larsen.

Sep 24, 1991:

	increased buffer in gsub.  a very crude fix to a general problem.

	and again on Sep 26.

Aug 18, 1991:

	enforce variable name syntax for commandline variables: has to

	start with letter or _.

Jul 27, 1991:

	allow newline after ; in for statements.

Jul 21, 1991:

	fixed so that in self-assignment like $1=$1, side effects

	like recomputing $0 take place.  (this is getting subtle.)

Jun 30, 1991:

	better test for detecting too-long output record.

Jun 2, 1991:

	better defense against very long printf strings.

	made break and continue illegal outside of loops.

May 13, 1991:

	removed extra arg on gettemp, tempfree.  minor error message rewording.

May 6, 1991:

	fixed silly bug in hex parsing in hexstr().

	removed an apparently unnecessary test in isnumber().

	warn about weird printf conversions.

	fixed unchecked array overwrite in relex().

	changed for (i in array) to access elements in sorted order.

	then unchanged it -- it really does run slower in too many cases.

	left the code in place, commented out.

Feb 10, 1991:

	check error status on all writes, to avoid banging on full disks.

Jan 28, 1991:

	awk -f - reads the program from stdin.

Jan 11, 1991:

	failed to set numeric state on $0 in cmd|getline context in run.c.

Nov 2, 1990:

	fixed sleazy test for integrality in getsval;  use modf.

Oct 29, 1990:

	fixed sleazy buggy code in lib.c that looked (incorrectly) for

	too long input lines.

Oct 14, 1990:

	fixed the bug on p. 198 in which it couldn't deduce that an

	argument was an array in some contexts.  replaced the error

	message in intest() by code that damn well makes it an array.

Oct 8, 1990:

	fixed horrible bug:  types and values were not preserved in

	some kinds of self-assignment. (in assign().)

Aug 24, 1990:

	changed NCHARS to 256 to handle 8-bit characters in strings

	presented to match(), etc.

Jun 26, 1990:

	changed struct rrow (awk.h) to use long instead of int for lval,

	since cfoll() stores a pointer in it.  now works better when int's

	are smaller than pointers!

May 6, 1990:

	AVA fixed the grammar so that ! is uniformly of the same precedence as

	unary + and -.  This renders illegal some constructs like !x=y, which

	now has to be parenthesized as !(x=y), and makes others work properly:

	!x+y is (!x)+y, and x!y is x !y, not two pattern-action statements.

	(These problems were pointed out by Bob Lenk of Posix.)

	Added \x to regular expressions (already in strings).

	Limited octal to octal digits; \8 and \9 are not octal.

	Centralized the code for parsing escapes in regular expressions.

	Added a bunch of tests to T.re and T.sub to verify some of this.

Feb 9, 1990:

	fixed null pointer dereference bug in main.c:  -F[nothing].  sigh.

	restored srand behavior:  it returns the current seed.

Jan 18, 1990:

	srand now returns previous seed value (0 to start).

Jan 5, 1990:

	fix potential problem in tran.c -- something was freed,

	then used in freesymtab.

Oct 18, 1989:

	another try to get the max number of open files set with

	relatively machine-independent code.

	small fix to input() in case of multiple reads after EOF.

Oct 11, 1989:

	FILENAME is now defined in the BEGIN block -- too many old

	programs broke.

	"-" means stdin in getline as well as on the commandline.

	added a bunch of casts to the code to tell the truth about

	char * vs. unsigned char *, a right royal pain.  added a

	setlocale call to the front of main, though probably no one

	has it usefully implemented yet.

Aug 24, 1989:

	removed redundant relational tests against nullnode if parse

	tree already had a relational at that point.

Aug 11, 1989:

	fixed bug:  commandline variable assignment has to look like

	var=something.  (consider the man page for =, in file =.1)

	changed number of arguments to functions to static arrays

	to avoid repeated malloc calls.

Aug 2, 1989:

	restored -F (space) separator

Jul 30, 1989:

	added -v x=1 y=2 ... for immediate commandline variable assignment;

	done before the BEGIN block for sure.  they have to precede the

	program if the program is on the commandline.

	Modified Aug 2 to require a separate -v for each assignment.

Jul 10, 1989:

	fixed ref-thru-zero bug in environment code in tran.c

Jun 23, 1989:

	add newline to usage message.

Jun 14, 1989:

	added some missing ansi printf conversion letters: %i %X %E %G.

	no sensible meaning for h or L, so they may not do what one expects.

	made %* conversions work.

	changed x^y so that if n is a positive integer, it's done

	by explicit multiplication, thus achieving maximum accuracy.

	(this should be done by pow() but it seems not to be locally.)

	done to x ^= y as well.

Jun 4, 1989:

	ENVIRON array contains environment: if shell variable V=thing,

		ENVIRON["V"] is "thing"

	multiple -f arguments permitted.  error reporting is naive.

	(they were permitted before, but only the last was used.)

	fixed a really stupid botch in the debugging macro dprintf

	fixed order of evaluation of commandline assignments to match

	what the book claims:  an argument of the form x=e is evaluated

	at the time it would have been opened if it were a filename (p 63).

	this invalidates the suggested answer to ex 4-1 (p 195).

	removed some code that permitted -F (space) fieldseparator,

	since it didn't quite work right anyway.  (restored aug 2)

Apr 27, 1989:

	Line number now accumulated correctly for comment lines.

Apr 26, 1989:

	Debugging output now includes a version date,

	if one compiles it into the source each time.

Apr 9, 1989:

	Changed grammar to prohibit constants as 3rd arg of sub and gsub;

	prevents class of overwriting-a-constant errors.  (Last one?)

	This invalidates the "banana" example on page 43 of the book.

	Added \a ("alert"), \v (vertical tab), \xhhh (hexadecimal),

	as in ANSI, for strings.  Rescinded the sloppiness that permitted

	non-octal digits in \ooo.  Warning:  not all compilers and libraries

	will be able to deal with \x correctly.

Jan 9, 1989:

	Fixed bug that caused tempcell list to contain a duplicate.

	The fix is kludgy.

Dec 17, 1988:

	Catches some more commandline errors in main.

	Removed redundant decl of modf in run.c (confuses some compilers).

	Warning:  there's no single declaration of malloc, etc., in awk.h

	that seems to satisfy all compilers.

Dec 7, 1988:

	Added a bit of code to error printing to avoid printing nulls.

	(Not clear that it actually would.)

Nov 27, 1988:

	With fear and trembling, modified the grammar to permit

	multiple pattern-action statements on one line without

	an explicit separator.  By definition, this capitulation

	to the ghost of ancient implementations remains undefined

	and thus subject to change without notice or apology.

	DO NOT COUNT ON IT.

Oct 30, 1988:

	Fixed bug in call() that failed to recover storage.

	A warning is now generated if there are more arguments

	in the call than in the definition (in lieu of fixing

	another storage leak).

Oct 20, 1988:

	Fixed %c:  if expr is numeric, use numeric value;

	otherwise print 1st char of string value.  still

	doesn't work if the value is 0 -- won't print \0.

	Added a few more checks for running out of malloc.