===================================================================
RCS file: /cvsrepo/anoncvs/cvs/src/usr.bin/awk/FIXES,v
retrieving revision 1.6
retrieving revision 1.7
diff -c -r1.6 -r1.7
*** src/usr.bin/awk/FIXES	1997/08/25 16:17:07	1.6
--- src/usr.bin/awk/FIXES	1999/04/18 17:06:29	1.7
***************
*** 1,4 ****
! /*	$OpenBSD: FIXES,v 1.6 1997/08/25 16:17:07 kstailey Exp $	*/
  /****************************************************************
  Copyright (C) Lucent Technologies 1997
  All Rights Reserved
--- 1,4 ----
! /*	$OpenBSD: FIXES,v 1.7 1999/04/18 17:06:29 millert Exp $	*/
  /****************************************************************
  Copyright (C) Lucent Technologies 1997
  All Rights Reserved
***************
*** 26,547 ****
  This file lists all bug fixes, changes, etc., made since the AWK book
  was sent to the printers in August, 1987.
  
! Sep 12, 1987:
! 	Very long printf strings caused core dump;
! 	fixed aprintf, asprintf, format to catch them.
! 	Can still get a core dump in printf itself.
  
! Sep 17, 1987:
! 	Error-message printer had printf(s) instead of
! 	printf("%s",s);  got core dumps when the message
! 	included a %.
  
! Oct xx, 1987:
! 	Reluctantly added toupper and tolower functions.
! 	Subject to rescinding without notice.
  
! Dec 2, 1987:
! 	Newer C compilers apply a strict scope rule to extern
! 	declarations within functions.  Two extern declarations in
! 	lib.c and tran.c have been moved to obviate this problem.
  
! Mar 25, 1988:
! 	main.c fixed to recognize -- as terminator of command-
! 	line options.  Illegal options flagged.
! 	Error reporting slightly cleaned up.
  
! May 10, 1988:
! 	Fixed lib.c to permit _ in commandline variable names.
  
! May 22, 1988:
! 	Removed limit on depth of function calls.
  
! May 28, 1988:
! 	srand returns seed value it's using.
! 	see 1/18/90
  
! June 1, 1988:
! 	check error status on close
  
! July 2, 1988:
! 	performance bug in b.c/cgoto(): not freeing some sets of states.
! 	partial fix only right now, and the number of states increased
! 	to make it less obvious.
  
! July 2, 1988:
! 	flush stdout before opening file or pipe
  
! July 24, 1988:
! 	fixed egregious error in toupper/tolower functions.
! 	still subject to rescinding, however.
  
! Aug 23, 1988:
! 	setting FILENAME in BEGIN caused core dump, apparently
! 	because it was freeing space not allocated by malloc.
  
! Sep 30, 1988:
! 	Now guarantees to evaluate all arguments of built-in
! 	functions, as in C;  the appearance is that arguments
! 	are evaluated before the function is called.  Places
! 	affected are sub (gsub was ok), substr, printf, and
! 	all the built-in arithmetic functions in bltin().
! 	A warning is generated if a bltin() is called with
! 	the wrong number of arguments.
  
! 	This requires changing makeprof on p167 of the book.
  
! Oct 12, 1988:
! 	Fixed bug in call() that freed local arrays twice.
  
! 	Fixed to handle deletion of non-existent array right;
! 	complains about attempt to delete non-array element.
  
! 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.
  
! 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).
  
! 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.
  
! Dec 7, 1988:
! 	Added a bit of code to error printing to avoid printing nulls.
! 	(Not clear that it actually would.)
  
! 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.
  
! Jan 9, 1989:
! 	Fixed bug that caused tempcell list to contain a duplicate.
! 	The fix is kludgy.
  
! 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.
  
! Apr 26, 1989:
! 	Debugging output now includes a version date,
! 	if one compiles it into the source each time.
  
! Apr 27, 1989:
! 	Line number now accumulated correctly for comment lines.
  
! 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)
  
! 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 23, 1989:
! 	add newline to usage message.
  
! Jul 10, 1989:
! 	fixed ref-thru-zero bug in environment code in tran.c
  
! 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.
  
! Aug 2, 1989:
! 	restored -F (space) separator
  
! 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 24, 1989:
! 	removed redundant relational tests against nullnode if parse
! 	tree already had a relational at that point.
  
! 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.
  
! 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.
  
! Jan 5, 1990:
! 	fix potential problem in tran.c -- something was freed,
! 	then used in freesymtab.
  
! Jan 18, 1990:
! 	srand now returns previous seed value (0 to start).
  
! Feb 9, 1990:
! 	fixed null pointer dereference bug in main.c:  -F[nothing].  sigh.
  
! 	restored srand behavior:  it returns the current seed.
  
! 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.
  
! 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!
  
! Aug 24, 1990:
! 	changed NCHARS to 256 to handle 8-bit characters in strings
! 	presented to match(), etc.
  
! Oct 8, 1990:
! 	fixed horrible bug:  types and values were not preserved in
! 	some kinds of self-assignment. (in assign().)
  
! 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 29, 1990:
! 	fixed sleazy buggy code in lib.c that looked (incorrectly) for
! 	too long input lines.
  
! Nov 2, 1990:
! 	fixed sleazy test for integrality in getsval;  use modf.
  
! Jan 11, 1991:
! 	failed to set numeric state on $0 in cmd|getline context in run.c.
  
! Jan 28, 1991:
! 	awk -f - reads the program from stdin.
  
! Feb 10, 1991:
! 	check error status on all writes, to avoid banging on full disks.
  
! 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.
  
! May 13, 1991:
! 	removed extra arg on gettemp, tempfree.  minor error message rewording.
  
! Jun 2, 1991:
! 	better defense against very long printf strings.
! 	made break and continue illegal outside of loops.
  
! Jun 30, 1991:
! 	better test for detecting too-long output record.
  
! Jul 21, 1991:
! 	fixed so that in self-assignment like $1=$1, side effects
! 	like recomputing $0 take place.  (this is getting subtle.)
  
! Jul 27, 1991:
! 	allow newline after ; in for statements.
  
! Aug 18, 1991:
! 	enforce variable name syntax for commandline variables: has to
! 	start with letter or _.
  
! Sep 24, 1991:
! 	increased buffer in gsub.  a very crude fix to a general problem.
! 	and again on Sep 26.
  
  Nov 12, 1991:
  	cranked up some fixed-size arrays in b.c, and added a test for
  	overflow in penter.  thanks to mark larsen.
  
! Nov 19, 1991:
! 	use RAND_MAX instead of literal in builtin().
  
! Nov 30, 1991:
! 	fixed storage leak in freefa, failing to recover [N]CCL.
! 	thanks to Bill Jones (jones@skorpio.usask.ca)
  
! Dec 2, 1991:
! 	die-casting time:  converted to ansi C, installed that.
  
! Feb 20, 1992:
! 	recompile after abortive changes;  should be unchanged.
  
! 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.
  
! Apr 24, 1992:
! 	remove redundant close of stdin when using -f -.
  
! 	got rid of core dump with -d; awk -d just prints date.
  
! 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.
  
! Nov 28, 1992:
! 	deleted yyunput and yyoutput from proto.h;
! 	different versions of lex give these different declarations.
  
! 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.
  
! Feb 2, 1994:
! 	changed error() to print line number as %d, not %g.
  
! 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.
  
! May 11, 1994:
! 	trivial fix to printf to limit string size in sub().
  
! Aug 24, 1994:
! 	detect duplicate arguments in function definitions (mdm).
  
! 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 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.
  
! Apr 29, 1996:
! 	replaced uchar by uschar everwhere; 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.
  
! 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.)
  
! 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 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 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.
  
! 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.
  
! Jun 29, 1996:
! 	fixed awful bug in new field splitting; didn't get all the places
! 	where input was done.
  
! Jul 8, 1996:
! 	fixed long-standing bug in sub, gsub(/a/, "\\\\&"); thanks to
! 	ralph corderoy.
  
! 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 23, 1997:
! 	falling off the end of a function returns "" and 0, not 0.
! 	thanks to arnold robbins.
  
! 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.
  
! 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.
  
! 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 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.
  
--- 26,608 ----
  This file lists all bug fixes, changes, etc., made since the AWK book
  was sent to the printers in August, 1987.
  
! Mar 5, 1999:
! 	after hearing from yet another innocent victim, changed 
! 	isnumber to is_number to avoid the problem caused by
! 	freeBSD gratuitously and incorrectly including the name
! 	isnumber in the standard header file ctype.h.
  
! 	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.
  
! 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 everwhere; 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.
  
! Oct 12, 1988:
! 	Fixed bug in call() that freed local arrays twice.
  
! 	Fixed to handle deletion of non-existent array right;
! 	complains about attempt to delete non-array element.
  
! Sep 30, 1988:
! 	Now guarantees to evaluate all arguments of built-in
! 	functions, as in C;  the appearance is that arguments
! 	are evaluated before the function is called.  Places
! 	affected are sub (gsub was ok), substr, printf, and
! 	all the built-in arithmetic functions in bltin().
! 	A warning is generated if a bltin() is called with
! 	the wrong number of arguments.
  
! 	This requires changing makeprof on p167 of the book.
  
! Aug 23, 1988:
! 	setting FILENAME in BEGIN caused core dump, apparently
! 	because it was freeing space not allocated by malloc.
  
! July 24, 1988:
! 	fixed egregious error in toupper/tolower functions.
! 	still subject to rescinding, however.
  
! July 2, 1988:
! 	flush stdout before opening file or pipe
! 
! July 2, 1988:
! 	performance bug in b.c/cgoto(): not freeing some sets of states.
! 	partial fix only right now, and the number of states increased
! 	to make it less obvious.
! 
! June 1, 1988:
! 	check error status on close
! 
! May 28, 1988:
! 	srand returns seed value it's using.
! 	see 1/18/90
! 
! May 22, 1988:
! 	Removed limit on depth of function calls.
! 
! May 10, 1988:
! 	Fixed lib.c to permit _ in commandline variable names.
! 
! Mar 25, 1988:
! 	main.c fixed to recognize -- as terminator of command-
! 	line options.  Illegal options flagged.
! 	Error reporting slightly cleaned up.
! 
! Dec 2, 1987:
! 	Newer C compilers apply a strict scope rule to extern
! 	declarations within functions.  Two extern declarations in
! 	lib.c and tran.c have been moved to obviate this problem.
! 
! Oct xx, 1987:
! 	Reluctantly added toupper and tolower functions.
! 	Subject to rescinding without notice.
! 
! Sep 17, 1987:
! 	Error-message printer had printf(s) instead of
! 	printf("%s",s);  got core dumps when the message
! 	included a %.
! 
! Sep 12, 1987:
! 	Very long printf strings caused core dump;
! 	fixed aprintf, asprintf, format to catch them.
! 	Can still get a core dump in printf itself.
!