Power-Programmierung/CD2.mdf/c/m_emacs/ue311c/history.c

Text File | 1991-10-30 | 82.6 KB | 1,751 lines

/*
 *    HISTORY.C:    Revision History for
 *
 *    MicroEMACS 3.11
 *        written by Daniel M. Lawrence
 *        based on code by Dave G. Conroy.
 *
 *    (C)Copyright 1988,1989,1990,1991 by Daniel M. Lawrence
 *    MicroEMACS 3.11 can be copied and distributed freely for any
 *    non-commercial purposes. MicroEMACS 3.11 can only be incorporated
 *    into commercial software with the permission of the current author.
 *
 * REVISION HISTORY:
 *
 * 1.0    Steve Wilhite, 30-Nov-85
 *    - Removed the old LK201 and VT100 logic. Added code to support the
 *      DEC Rainbow keyboard (which is a LK201 layout) using the the Level
 *      1 Console In ROM INT. See "rainbow.h" for the function key defs
 *    Steve Wilhite, 1-Dec-85
 *    - massive cleanup on code in display.c and search.c
 *
 * 2.0    George Jones, 12-Dec-85
 *    - Ported to Amiga.
 *
 * 3.0    Daniel Lawrence, 29-Dec-85
 *    - rebound keys/added new fast buffered I/O for AMIGA
 *    - added META- repeat commands
 *    - added reposition default to center screen (yeah!)
 *    - changed exit with modified buffers message
 *    - made filesave tell us what it is doing
 *    - changed search string entry to terminate with <ESC>
 *      so we can use <NL> in search/replace strings
 *    - updated version number in mode line to 3.0
 *    12-Jan-86
 *    - Added code to reconize the search/replace functions
 *    - Added code to perform search/replace & query functions
 *    14-Jan-86
 *    - moved search logic to separate function in search.c
 *    - added replace and query replace functions
 *    - separated out control key expansions to be used by others in search.c
 *    15-Jan-86
 *    - changed "visiting" to finding
 *    - changed yes/no responses to not need return
 *    - cleaned up various messages
 *    16-jan-86
 *    - fixed spurious spawn message in MSDOS
 *    - added ^X-S synonym to save command
 *    - moved escape to shell to ^X-C
 *    21-jan-86
 *    - added code to suspend shell under BSD
 *    22-jan-86
 *    - added function key support (SPEC) under MSDOS
 *    - Abort now prints [Aborted] on message line
 *    23-jan-86
 *    - Added modes and commands to set/unset them
 *    24-jan-86
 *    - Added Goto Line command
 *    - added Rename Buffer command
 *    28-jan-86
 *    - added goto beginning and end of paragraph commands (META-P/META-N)
 *    - re-wrote kdelete to use realloc. Gained MUCH speed here when
 *      doing large wipes on both UNIX and MSDOS. Changed kill buffer
 *      allocation block size from 256 bytes to 1 k
 *    29-jan-86
 *    - moved extern function declarations to efunc.h
 *    - made name[] name binding table
 *    30-jan-86
 *    - fixed Previous/Next paragraph command not to wrap around EOF
 *    - added Fill Paragraph command (META-Q)
 *    4-feb-86
 *    - added code to properly display long lines, scrolling them right
 *      to left
 *    5-feb-85
 *    - rewrote code to right/left scroll...much better
 *    - added shifted arrow keys on IBMPC
 *    6-feb-85
 *    - add option to allow forward-word to jump to beginning of
 *      next word instead of end of current one. This is different from
 *      other emacs' but can be configured off in estruct.h
 *    - added VIEW mode to allow a buffer to be read only
 *       (-v switch on command line will activate this)
 *    - changed quick exit to write out ALL changed buffers!!!
 *      MAKE SURE YOU KNOW THIS WHEN META-Zing
 *    10-feb-86
 *    - added handling of lines longer than allowed on file read in
 *      (they wrap on additional lines)
 *    - made having space clear the message line and NOT insert itself
 *      a configuration option in ed.h
 *    11-feb-86
 *    - added Describe-command and Help commands.
 *    13-feb-86
 *    - added View file command (^X ^V) and finished HELP command
 *    14-feb-86
 *    - added option to let main loop skip update if type ahead commands
 *       are queued up
 *    16-feb-86
 *    - added Insert File command
 *    17-feb-86
 *    - added scroll next window up/down commands
 *    18-feb-86
 *    - added CMODE indentation
 *    - re-arranged header files to standardize extern and global
 *      definitions
 *    - changed version number to 3.2
 *    - added numeric arguments to search, reverse search and
 *      search and replace
 *    24-feb-86
 *    - added Bind To Key function (^C for now) to allow the user
 *      to change his command keys
 *    - added Unbind key function (M-^C for now)
 *    - added execute named command to execute unbound commands (M-X)
 *    - added describe bindings command (not bound)
 *    - changed version number to 3.3
 *    25-feb-86
 *    - scrapped CERROR mode (too many compilers)
 *    - added EXACT mode for case sensitive searchers
 *    26-feb-86
 *    - added command completion on execute named command and
 *      all routined grabbing a command name
 *    - adding execute-command-line command and its support functions
 *      (in preparation for sourcing files)
 *    - added Execute Buffer command
 *    27-feb-86
 *    - added execute(source) file command and added code to automatically
 *      execute emacs.rc (or .emacsrc on UNIX) before initial read in
 *    - changed version number to 3.4
 *    4-mar-86
 *    - changed word delete to be consistant with word move (it gets
 *      rid of the inter word space now) This is configurable with the
 *      NFWORD symbol in estruct.h
 *    - added B_ACTIVE entry to the buffer table. Let emacs read multiple
 *      file names from the command line and only read them in as needed
 *    5-mar-85
 *    - rewrote command line parser to get rid of my patchy code
 *    - changed version number to 3.5
 *    1-apr-86
 *    - added support for Aztec C 3.20e under MSDOS
 *    - fixed bug in mlwrite on ADM3's and their ilk under V7
 *    - added insertion of pounds in column one under CMODE
 *    - changed version number to 3.6
 *    3-apr-86
 *    - added next-buffer command (^X-X)
 *    5-apr-86
 *    - added kill paragraph command (M-^W)
 *    - changed fill-paragraph to leave 2 spaces after a period at the
 *      end of a word.
 *    - added OVERWRITE mode
 *    7-apr-86
 *    - fixed overwrite mode to handle tabs
 *    8-apr-86
 *    - added add/delete global mode (<ESC>M & <ESC> ^M) commands
 *    9-apr-86
 *    - added insert space command
 *    - moved bindings around     ^C    insert space
 *                    M-K    bind-to-key
 *                    INSERT    insert space
 *                    DELETE    forwdel
 *    - added hunt forward and hunt reverse commands
 *    10-apr-86
 *    - fixed bug in DOBUF with non-terminated command string
 *    15-apr-86
 *    - fixed tab expansion bug in DISPLAY which hung the AMIGA
 *      (sent in by Dawn Banks)
 *    - fixed curcol problen if forwline/backline during keyboard
 *      macro execution (sent in by Ernst Christen)
 *    - added AMIGA function/cursor key support
 *    - fixed nonterminating <NL> replacement bug
 *    - fixed word wrapping problems
 *    16-apr-86
 *    - updated documentation and froze development for 3.6 net release
 *    23-apr-86    version 3.6a
 *    - added foreground and background colors. Setable with the
 *      add mode commands for the moment
 *    24-apr-86
 *    - added command to pipe CLI output to a buffer
 *    25-apr-86
 *    - added Dana Hoggatt's code to replace Lattice's sick system()
 *      function. Now we no longer care what the switchar is.
 *    - cleaned up the positioning on several of the spawing commands
 *    26-apr-86
 *    - added an output flush in vttidy(). Unix really appreciates this.
 *    - added filter-buffer (^X#) command to send a buffer through
 *      a DOS filter
 *    - made automatic CMODE on .c and .h file compilation dependant
 *      in estruct.h
 *    1-may-86
 *    - optimized some code in update(). It certainly needs a lot more.
 *    - added Aztec profiling capabilities. These are conditional on
 *      the APROF symbol in estruct.h
 *    2-may-86
 *    - added (u)ndo command in query-replace. undoes last repalce.
 *    6-may-86
 *    - re-organized and wrote the update() function in display.c
 *      Now my color hacks are in the right places and the code can be
 *      understood.
 *    [Released version 3.6f for BETA test sites]
 *    8-may-86
 *    - fixed bug in new display routine to wrap cursor on extended
 *      lines at the right time
 *    - modified the buffer-position command to give reasonable info
 *    9-may-86
 *    - improved the word wrap algorithm as not to discard non-space
 *      delimiters. The backscan now looks for white space rather than
 *      !inword().
 *    [Released version 3.6g to Krannert]
 *    10-may-86
 *    - Added IBMPC.C an IBM-PC specific display driver. This makes paging
 *      4-6 times faster. Also made some conditional changes to DISPLAY.C
 *      to eliminate the pscreen[] if using the PC driver.
 *    [changed version number to 3.6i]
 *    12-may-86
 *    - added delete-window (^X 0) command to dispose of a single window
 *    - fixed problem with multiple prefixes from a command line which
 *      was reported by John Gamble
 *    14-may-86
 *    - Added Aztec support for the IBMPC display driver. Had to
 *      readjust some includes and defines for this.
 *    - fixed bug in delete-window.
 *    - fixed some bizarre behavior with the cursor after coming back
 *      from spawn calls.
 *    [changed version number to 3.7 freezing development for net release]
 *    15-may-86
 *    - (that didn't last long...) Added execute-macro-(1 thru 20) commands
 *      to execute macro buffers (named "[Macro nn]")
 *    - changed BFTEMP to BFINVS and cleaned up treatment of invisible
 *      buffers.
 *    16-may-86
 *    - added store-macro (unbound) to store any executed command lines to
 *      macro buffer.
 *    - added clear-message-line (unbound) command to do just that
 *    - added resize-window command to change a window's size to the
 *      specified argument
 *    - improved help's logic not to re-read the file if it was already
 *      in a buffer
 *    - added MAGIC mode to all structures and command tables, but the
 *      regular expression code that John Gamble is writing is not ready.
 *    18-may-86
 *    - added interactive prompt requests in command line execution (i.e.
 *      while executing a macro, a parameter starting with an at sign (@)
 *      causes emacs to prompt with the rest of the parameter and return
 *      the resulting input as the value of the parameter).
 *    - added arguments to split-current-window to force the cursor into
 *      the upper or lower window.
 *    20-may-86
 *    - added support for the Microsoft C compiler as per the changes
 *      sent in by Oliver Sharp
 *    - made some upgrades and fixes for VMS sent in by Guy Streeter
 *    21-may-86
 *    - fixed an Aztec bug in ttgetc by clearing the upper byte
 *    - fixed buf in CMODE with #preprocesser input (bug fix submitted by
 *      Willis of unknown path)
 *    - added support of alternative startup file ( @<filename> ) in
 *      the command line
 *    - added ^Q quoting in interactive input (mltreply()).
 *    - added re-binding of meta-prefix and ctlx-prefix
 *    22-may-86
 *    - reorganized getkey routines to make more sense and let prefix
 *      binding work properly.
 *    23-may-86
 *    - checked new code on BSD4.2 and made a few fixes
 *    - added optional fence matching while in CMODE
 *    - added goto and search command line arguments by Mike Spitzer
 *    26-may-86
 *    - added parameter fetching from buffers
 *    27-may-86
 *    - fixed some HP150 bugs......
 *    31-may-86
 *    - Added Wang PC keyboard support from modifications by
 *      Sid Shapiro @ Wang Institute
 *    - Fixed some reverse video bugs with code submitted by Peter Chubb
 *    - Fixed bug in nextbuffer reported by Dave Forslund
 *    - added system V support (USG) from Linwood Varney
 *    2-jun-86
 *    - changed defines to just define one Unix define (for example,
 *      just define BSD for Unix BSD 4.2)
 *    - Added Incremental search functions written by D. R. Banks
 *      in file ISEARCH.C
 *    - added insert-string (unbound) command to help the macro
 *      language out.
 *    - added unmark-buffer (M-~) command to turn off the current buffers
 *      change flag
 *    - fixed nxtarg to truncate strings longer than asked for max length
 *    4-jun-86
 *    - added special characters in command line tokens. Tilde (~) is
 *      the special lead-in character for "nrtb".
 *    - Fixed bad ifdef in Aztec code so it could look at HOME dir
 *      for startup, help, and emacs.rc files
 *    6-jun-86
 *    - make delete word commands clear the kill buffer if not after another
 *      kill command
 *    11-jun-86
 *    - made ~@ in string arguments pass as char(192) to nxtarg() so one can
 *      quote @ at the beginning of string arguments
 *    - changed buffer size vars in listbuffers() to long (for big files)
 *    - re-wrote buffer-position command to be much faster
 *    12-jun-86
 *    - added count-words (M-^C) command to count the words/chars and
 *      lines in a region
 *    - changed regions so they could be larger than 65535 (short ->
 *      long in the REGION structure)
 *    - changed ldelete() and all callers to use a long size. The kill
 *      buffer will still have a problem >65535 that can not be solved
 *      until I restructure it.
 *    - grouped paragraph commands and word count together under symbol
 *      WORDPRO to allow them to be conditionally made (or not)
 *    13-jun-86
 *    - re-wrote kill buffer routines again. Now they support an unlimited
 *      size kill buffer, and are (in theory) faster.
 *    - changed delete-next-word (M-D) to not eat the newline after a word,
 *      instead it checks and eats a newline at the cursor.
 *    17-jun-86
 *    - added numeric argument to next/previous-window to access the nth
 *      window from the top/bottom
 *    - added support for the Data General 10 MSDOS machine
 *    - added save-window (unbound) and restore-window (unbound) commands
 *      for the use of the menu script. Save-window remembers which window
 *      is current, and restore-window returns the cursor to that window.
 *    20-jun-86
 *    - fixed a bug with the fence matching locking up PASCAL NEAR the beginning
 *      of a buffer
 *    - added argument to update to selectively force a complete update
 *    - added update-screen (unbound) command so macros can force a
 *      screen update
 *    21-jun-86
 *    - rearranged token() and nxtarg() calls so that command names and
 *      repeat counts could also be prompted and fetched from buffers
 *      [this broke later with the exec re-write....]
 *    - added write-message (unbound) command to write out a message
 *      on the message line (for macros)
 *    - changed ifdef's so that color modes are recognized as legal in
 *      b/w version, and simply do nothing (allowing us to use the same
 *      script files)
 *    [Released version 3.7 on July 1 to the net and elswhere]
 *    2-jul-86
 *    - Changed search string terminator to always be the meta character
 *      even if it is rebound.
 *    3-jul-86
 *    - removed extra calls to set color in startup code. This caused the
 *      original current window to always be the global colors.
 *    7-jul-86
 *    - Fixed bugs in mltreply() to work properly with all terminators
 *      including control and spec characters
 *    22-jul-86
 *    - fixed replaces() so that it will return FALSE properly on the
 *      input of the replacement string.
 *    - added a definition for FAILED as a return type.....
 *    - changed version number to 3.7b
 *    23-jul-86
 *    - fixed o -> 0 problem in TERMIO.C
 *    - made ^U universal-argument re-bindable
 *    - wrote asc_int() for systems (like Aztec) where it acts strangely
 *    - changed version number to 3.7c
 *    25-jul-86
 *    - make ^G abort-command rebindable
 *    29-jul-86
 *    - added HP110 Portable Computer support
 *    - changed version number to 3.7d
 *    30-jul-86
 *    - Fixed a couple of errors in the new VMS code as pointer
 *      out by Ken Shackleford
 *    - split terminal open/close routines into screen and keyboard
 *      open/close routines
 *    - closed the keyboard during all disk I/O so that OS errors
 *      can be respoded to correctly (especially on the HP150)
 *    - changed version number to 3.7e
 *    31-jul-86
 *    - added label-function-key (unbound) command under symbol FLABEL
 *      (primarily for the HP150)
 *    4-aug-86
 *    - added fixes for Microsoft C as suggested by ihnp4!ihuxm!gmd1
 *        <<remember to fix [list] deletion bug as reported
 *          by craig@hp-pcd>>
 *    8-aug-86
 *    - fixed beginning misspelling error everywhere
 *    - fixed some more MSC errors
 *    - changed version number to 3.7g
 *    ?-aug-86 John M. Gamble:
 *    - Made forward and reverse search use the same scan routine.
 *    - Added a limited number of regular expressions - 'any',
 *      'character class', 'closure', 'beginning of line', and
 *      'end of line'.
 *    - Replacement metacharacters will have to wait for a re-write of
 *      the replaces function, and a new variation of ldelete().
 *    - (For those curious as to my references, i made use of
 *      Kernighan & Plauger's "Software Tools."
 *      I deliberately did not look at any published grep or editor
 *      source (aside from this one) for inspiration.  I did make use of
 *      Allen Hollub's bitmap routines as published in Doctor Dobb's Journal,
 *      June, 1985 and modified them for the limited needs of character class
 *      matching.  Any inefficiences, bugs, stupid coding examples, etc.,
 *      are therefore my own responsibility.)
 *    20-aug-86 Daniel Lawrence
 *    - fixed CMODE .h scanning bug
 *    - changed version number to 3.7h
 *    30-aug-86
 *    - fixed killing renamed [list] buffer (it can't) as submitted
 *      by James Aldridge
 *    - Added code to allow multiple lines to display during
 *      vertical retrace
 *      [total disaster....yanked it back out]
 *    9-sep-86
 *    - added M-A (apropos) command to list commands containing a substring.
 *    - fixed an inefficiency in the display update code submitted
 *      by William W. Carlson (wwc@pur-ee)
 *    10-sep-86
 *    - added Dana Hoggatt's code for encryption and spliced it into the
 *      proper commands. CRYPT mode now triggers encryption.
 *    - added -k flag to allow encryption key (no spaces) in command line
 *    14-sep-86
 *    - added missing lastflag/thisflag processing to docmd()
 *    - changed version to 3.7i and froze for partial release via mail
 *      and BBS
 *    05-oct-86
 *    - changed some strcpys in MAIN.C to bytecopys as suggested by John
 *      Gamble
 *    - replaces SEARCH.C and ISEARCH.C with versions modified by
 *      John Gamble
 *    10-oct-86
 *    - removed references to lflick....it just won't work that way.
 *    - removed defines LAT2 and LAT3...the code no longer is Lattice
 *      version dependant.
 *    14-oct-86
 *    - changed spawn so that it will not not pause if executed from
 *      a command line
 *    15-oct-86
 *    - added argument concatination (+) to the macro parsing
 *    - added [] as fence pairs
 *    16-oct-86
 *    - rewrote all macro line parsing routines and rearranged the
 *      mlreply code. Saved 6K!!! Have blazed the path for expanding
 *      the command language.
 *    17-oct-86
 *    - added new keyboard macro routines (plus a new level to the
 *      input character function)
 *    22-oct-86
 *    - improved EGA cursor problems
 *    - added -r (restricted) switch to command line for BBS use
 *    06-nov-86
 *    - fixed terminator declarations from char to int in getarg() and
 *      nxtarg() in EXEC.C as pointed out by John Gamble
 *    07-nov-86
 *    - made wordrap() user callable as wrap-word (M-FNW) and changed
 *      the getckey() routine so that illegal keystrokes (too many
 *      prefixes set) could be used for internal bindings. When word
 *      wrap conditions are met, the keystroke M-FNW is executed. Added
 *      word wrap check/call to newline().
 *    11-nov-86
 *    - added and checked support for Mark Williams C 86
 *    12-nov-86
 *    - added goto-matching-fence (M-^F) command to jump to a matching
 *      fence "({[]})" or beep if there is none. This can reframe the
 *      screen.
 *    - added code and structure elements to support change-screen-size
 *      command (M-^S) to change the number of lines being used by
 *      MicroEMACS.
 *    15-nov-86
 *    - finished debugging change-screen-size
 *    17-nov-86
 *    - Incorporated in James Turner's modifications for the Atari ST
 *        23-sep-86
 *        - added support for the Atari ST line of computers (jmt)
 *          - added a '\r' to the end of each line on output and strip
 *            it on input for the SHOW function from the desktop
 *          - added 3 new mode functions (HIREZ, MEDREZ, and LOREZ);
 *            chgrez routine in TERM structure; and MULTREZ define in
 *            ESTRUCT.H to handle multiple screen resolutions
 *    [note....ST still not running under Lattice yet...]
 *    25-nov-86
 *    - Made the filter-buffer (^X-#) command not work on VIEW mode
 *      buffers
 *    - Made the quick-exit (M-Z) command throw out a newline after
 *      each message so they could be seen.
 *    26-nov-86
 *    - fixed a couple of bugs in change-screen-size (M-^S) command
 *    - changed file read behavior on long lines and last lines
 *      with no newline (it no longer throws the partial line out)
 *    - [as suggested by Dave Tweten] Made adding a ^Z to the end
 *      of an output file under MSDOS configurable under the
 *      CTRL-Z symbol in ESTRUCT.H
 *    - [Dave Tweten] Spawn will look up the "TMP" environment variable
 *      for use during various pipeing commands.
 *    - [Dave Tweten] changed pipe command under MSDOS to use '>>'
 *      instead of '>'
 *    04-dec-86
 *    - moved processing of '@' and '#' so that they can be outside
 *      the quotes in an argument, and added hooks to process '%' for
 *      environment and user variables.
 *    - modified IBMPC.C to sense the graphics adapter (CGA and MONO)
 *      at runtime to cut down on the number of versions.
 *    05-dec-86
 *    - changed macro directive character to "!" instead of "$" (see
 *      below) and fixed the standard .rc file to comply.
 *    - added code to interpret environment variables ($vars). Added
 *      hooks for built in functions (&func). So, to recap:
 *
 *        @<string>    prompt and return a string from the user
 *        #<buffer name>    get the next line from a buffer and advance
 *        %<var>        get user variable <var>
 *        $<evar>     get environment variable <evar>
 *        &<func>     evaluate function <func>
 *
 *    - allowed repeat counts to be any of the above
 *    - added code to allow insert-string (unbound) to use its
 *      repeat count properly
 *    - added set (^X-A) command to set variables. Only works on
 *      environmental vars yet.
 *    9-dec-86
 *    - added some code for user defined variables...more to come
 *    - added options for malloc() memory pool tracking
 *    - preliminary user variables (%) working
 *    - changed terminal calls to macro's (to prepare for the new
 *      terminal drivers)
 *    15-dec-86
 *    - changed previous-line (^P) and next-line (^N) to return a
 *      FALSE at the end or beginning of the file so repeated
 *      macros involving them terminate properly!
 *    - added code for $CURCOL and $CURLINE
 *    20-dec-86
 *    - set (^X-A) now works with all vars
 *    - added some new functions
 *        &ADD &SUB &TIMES &DIV &MOD &NEG &CAT
 *    - once again rearranged functions to control macro execution. Did
 *      away with getarg()
 *    23-dec-86
 *    - added string functions
 *        &LEFt &RIGht &MID
 *    31-dec-86
 *    - added many logical functions
 *        &NOT &EQUal &LESs &GREater
 *    - added string functions
 *        &SEQual &SLEss &SGReater
 *    - added variable indirection with &INDirect
 *    - made fixes to allow recursive macro executions
 *      (improved speed during macro execution as well)
 *    3-jan-87
 *    - added $FLICKER to control flicker supression
 *    - made spawn commands restricted
 *    - cleaned up lots of unintentional int<->char problems
 *    4-jan-87
 *    - Fixed broken pipe-command (^X-@) command under MSDOS
 *    - added !IF  !ELSE  !ENDIF  directives and changed the
 *      name of !END to !ENDM....real slick stuff
 *    5-jan-87
 *    - quick-exit (M-Z) aborts on any filewrite errors
 *    8-jan-87
 *    - debugged a lot of the new directive and evaluation code.
 *      BEWARE of stack space overflows! (increasing stack to
 *      16K under MSDOS)
 *    - removed non-standard DEC Rainbow keyboard support...let someone
 *      PLEASE implement this in the standard manner using key bindings
 *      and send the results to me.
 *    - added change-screen-width () command and $CURWIDTH variable
 *    11-jan-87
 *    - fixed an incredibly deeply buried bug in vtputc and combined
 *      it with vtpute (saving about 200 bytes!)
 *    16-jan-87
 *    - added code to handle controlling multiple screen resolutions...
 *      allowed the IBM-PC driver to force Mono or CGA modes.
 *    - added current buffer name and filename variables
 *      $cbufname and $cfname
 *    18-jan-87
 *    - added $sres variable to control screen resolution
 *    - added $debug variable to control macro debugging code (no longer
 *      is this activated by GLOBAL spell mode)
 *    - fixed bug in -g command line option
 *    - Released Version 3.8 to BBSNET
 *    21-jan-87
 *    - added $status variable to record return status of last command
 *    2-feb-87
 *    - added ATARI 1040 support...runs in all three modes right now
 *    - added $palette var with palette value in it
 *    - undefined "register" in BIND.C and INPUT.C for ST520 & LATTICE
 *      to get around a nasty Lattice bug
 *    4-feb-87
 *    - added, debugged code for switching all 1040ST color modes, added
 *      code for HIGH monochrome mode as well, DENSE still pending
 *    5-feb-87
 *    - with John Gamble, found and corrected the infamous bad matching
 *      fence problems.
 *    - added error return check in various add/delete mode commands
 *    10-feb-87
 *    - re-arrange code in docmd() so that labels are stored in
 *      macro buffers
 *    - fixed !RETURN to only return if (execlevel == 0) [If we are
 *      currently executing]
 *    14-feb-87
 *    - added to outp() calls in the EGA driver to fix a bug in the BIOS
 *    - adding code for 1040ST 40 line DENSE mode (not complete)
 *    25-feb-87
 *    - added auto-save "ASAVE" mode....variables $asave and $acount
 *      control the frequency of saving and count until next save
 *    - added &and and &or as functions for logical anding and oring
 *    - added string length &LEN, upper and lower case string funtions
 *      &LOWER and &UPPER
 *    27-feb-87
 *    - added $lastkey   last keystroke struck and
 *        $curchar    character under cursor
 *    28-feb-87
 *    - added code for trim-line (^X^T) command and table entries
 *      for the entab-line (^X^E) and detab-line (^X^D) commands.
 *      These are conditional on AEDIT (Advanced editing) in estruct.h
 *    18-mar-87
 *    - finished above three commands
 *    - added $version environment variable to return the current
 *      MicroEMACS version number
 *    - added $discmd emvironment variable. This is a logical flag that
 *      indicates if emacs should be echoing commands on the command line.
 *      real useful in order to stop flashing macros and .rc files
 *    - added $progname environment variable. this always returns the
 *      string "MicroEMACS". OEM's should change this so that macros can
 *      tell if they are running on an unmodified emacs or not.
 *    - fixed a minor bug in the CGA/MONO detection routine in IBMPC.C
 *    20-mar-87
 *    - integrated EGAPC.C into IBMPC.C and eliminated the file. Now an
 *      EGA user can switch from EGA to CGA modes at will
 *    - A LOT of little fixes and corrections sent in by John Ruply
 *    25-mar-87
 *    - Fixed buffer variables so they will work when referencing the
 *      current buffer
 *    26-mar-87
 *    - Fixed asc_int() to be more reasonable. trailing whitespace ignored,
 *      only one leading sign, no non-digits allowed after the sign.
 *    - fixed buffer variables to go from the point to the end of
 *      line.
 *    28-mar-87
 *    - fixed bugs with 8 bit chars as submited by Jari Salminen
 *    - replace AZTEC/MSDOS agetc() with a1getc() which won't strip
 *      the high order bit
 *    30-mar-87
 *    - changed list-buffers (^X^B) so that with any argument, it will
 *      also list the normally invisable buffers
 *    - added store-procedure and execute-procedure/run (M-^E)
 *      commands to store and execute named procedures.
 *    31-mar-87
 *    - Fixed infinite loop in ^X-X command (when [LIST] is the
 *      only buffer left) as pointed out by John Maline
 *    - made filenames in getfile() always lower case as pointed
 *      out by John Maline
 *    2-apr-87
 *    - Fixed buffer variables so they would work on non-current displayed
 *      buffers. They should now work with ALL buffers....
 *    3-apr-87
 *    - Yanked AZTEC profiling code....not very useful
 *    - Modified IBMPC driver so it will not start in EGA mode
 *    - allow the next-buffer (^X-X) command to have a preceding
 *      non-negative argument.
 *    14-april-87: John M. Gamble
 *    - Deleted the "if (n == 0) n = 1;" statements in front of the
 *      search/hunt routines.  Since we now use a do loop, these
 *      checks are unnecessary.  Consolidated common code into the
 *      function delins().  Renamed global mclen matchlen,
 *      and added the globals matchline, matchoff, patmatch, and
 *      mlenold.
 *      This gave us the ability to unreplace regular expression searches,
 *      and to put the matched string into an evironment variable.
 *      SOON TO COME: Meta-replacement characters!
 *    14-apr-87 Daniel Lawrence
 *    - added John Gamble's modified search.c. The code has cut apx
 *      200-300 bytes off the executable.
 *    - added the &RND function to generate a random integer between
 *      1 and its arguments value. Also $SEED is availible as the
 *      random number seed.
 *    - changed the -k command line switch so if there is no argument,
 *      it will prompt for one when the file is read
 *    15-apr-87
 *    - added 20 bytes of buffer in getval()'s local argument alloc so
 *      when it returns a value, it has enough stack space to do at least
 *      one strcpy() before stomping on the returned value. ALWAYS call
 *      getval() ONLY from within a strcpy() call.
 *    - made $curcol return a 1 based value instead of a zero based one.
 *      [changed this back later for 3.8o   it was simply wrong.....]
 *    16-apr-87
 *    - re-wrote bytecopy() for AZTEC & MSDOS so it null terminates the
 *      string.
 *    - changed pipe() to pipecmd() to avoid conflicts with various
 *      UNIX systems
 *    24-apr-87
 *    - changed open parameters on AMIGA window open to 0/0/640/200
 *    25-apr-87    DML
 *    - cleaned up an unneccessary if/else in forwsearch() and
 *      backsearch()
 *    - savematch() failed to malloc room for the terminating byte
 *      of the match string (stomp...stomp...). It does now. Also
 *      it now returns gracefully if malloc fails
 *    [Froze and released v3.8i via BBS net]
 *    14-may-87
 *    - added nop (M-FNC) that gets called on every command loop
 *    - added $wline, returns and sets # lines in current window
 *    - added $cwline, returns and set current line within window
 *    - added $target, returns/sets target for line moves
 *    - added $search, returns/sets default search string
 *    - added $replace, returns/sets default replace string
 *    - added $match, returns last matched string in magic search
 *    29-may-87
 *    - rewrote word deletes to not kill trailing non-whitespace after
 *      the last word. Also a zero argument will cause it to just delete
 *      the word and nothing else.
 *    - more fixes for the search pattern environment variables
 *    30-may-87
 *    - forced all windows to redraw on a width change
 *    2-jun-87
 *    - forced clear-message-line to overide $discmd
 *    - added mlforce() routine and call it in clear-message-line,
 *      write-message and when $debug is TRUE
 *    - recoded the startup sequence in main()....Much Better...
 *    4-jun-87
 *    - forced interactive arguments ( @"question" ) to ALWAYS be echoed
 *      regardless of the setting of $discmd.
 *    7-jun-87
 *    - started adding support for Turbo C under MSDOS
 *    11-jun-87
 *    - words now include ONLY upper/lower case alphas and digits
 *    - fixed some more bugs with the startup..(ORed in the global modes)
 *    - took more limits off the self-insert list....
 *    16-jun-87
 *    - macro debugging now displays the name of the current macro.
 *    - fixed a problem in expandp() in search.c that kept high-byte
 *      characters from working in search strings
 *    18-jun-87
 *    - added &sindex <str1> <str2> function which searches for string 2
 *      within string 1
 *    [released verion 3.8o internally]
 *    19-jun-87
 *    - added $cmode and $gmode to return and set the mode of the
 *      current buffer and the global mode
 *    - separated findvar() out from setvar() so it could be used in
 *      the !LOOP directive (which got canned....read on)
 *    - %No such variable message now types the name of the offending
 *      variable
 *    22-jun-87
 *    - fixed startup bug when editing the startup file
 *    - added the !LOOP <var> <label> directive
 *    26-jun-87
 *    - dumped !LOOP......added !WHILE. This needed and caused a vaste
 *      reorginization in exec.c which mainly involved moving all the
 *      directive handling from docmd() to dobuf(), in the process
 *      getting rid of a lot of junk and making the result smaller
 *      than it started.....(yea!)
 *    - added $tpause to control the fence flashing time in CMODE.
 *      The value is machine dependant, but you can multiply the
 *      original in macros to stay machine independant. (as
 *      suggested by Baron O.A. Grey)
 *    - added hook to execute M-FNR (null) during a file read, after
 *      the name is set and right before the file is read. Took out
 *      any auto-CMODE code, as this is now handled with a macro.
 *      (also suggested by Baron O.A. Grey)
 *    - Added Baron O.A. Grey's SYSTEM V typeahead() code...I hope
 *      this works....if you check this out, drop me a line.
 *    - Added new variable $pending, returns a logical telling if
 *      a typed ahead character is pending.
 *    29-jun-87
 *    - Made adjustmode() use curbp-> instead of curwp->w_bufp-> which
 *      fixed some bugs in the startup routines.
 *    - added $lwidth to return the length of the current line
 *    2-jul-87
 *    - Added &env <str> which returns the value of the environment
 *      variable <str> where possible
 *    - Fixed a NASTY bug in execbuf()..the buffer for the name
 *      of the buffer to execute was NBUFN long, and got overflowed
 *      with a long interactive argument.
 *    3-jul-87
 *    - Moved the loop to match a key against its binding out of execute()
 *      to getbind() so it could be used later elsewhere.
 *    - Added &bind <keyname> which returns the function bound to the
 *      named key
 *    - changed execute-file to look in the executable path first...
 *    6-jul-87
 *    - changed $curchar to return a newline at the end of a line and
 *      it no longer advances the cursor
 *    - a lot of minor changes sent by various people....
 *    7-jul-87
 *    - some amiga specific fixes as suggested by Kenn Barry
 *    - added $line [read/write] that contains the current line in the
 *      current buffer
 *    - changed $curcol so setting it beyond the end of the line will
 *      move the cursor to the end of the line and then fail.
 *    10-jul-87
 *    - added a number of fixes and optimizations along with the rest
 *      of the TURBO-C support as submited by John Maline
 *    13-jun-87
 *    - caused dobuf() to copy lastflag to thisflag so the first
 *      command executed will inherit the lastflag from the command
 *      before the execute-buffer command. (needed this for smooth
 *      scrolling to work)
 *    - made flook() look first in the $HOME directory, then in the
 *      current directory, then down the $PATH, and then in the
 *      list in epath.h
 *    14-jul-87
 *    - added some fixes for VMS along with support for the SMG
 *      screen package as submited by Curtis Smith
 *    15-jul-87
 *    - fixed M-^H (delete-previous-word) so it can delete the first
 *      word in a file....I think there may be more of this kind of thing
 *      to fix.
 *    16-jul-87
 *    - added code to allow arbitrary sized lines to be read from files..
 *      speed up file reading in the process.
 *    - made out of memory conditions safer.. especial on file reads
 *    - fixed a bug in bind having to do with uppercasing function
 *      key names (submitted by Jari Salminen)
 *    - made ST520 exit in the same resolution that EMACS was started in
 *      (for the 1040ST)
 *    20-jul-87: John M. Gamble
 *    - Set the variables matchlen and matchoff in the 'unreplace'
 *      section of replaces().  The function savematch() would
 *      get confused if you replaced, unreplaced, then replaced
 *      again (serves you right for being so wishy-washy...)
 *    [FROZE development and released version 3.9 to USENET]
 *    {It never made it.....got killed by comp.unix.sources}
 *    12-aug-87: John M. Gamble
 *    - Put new function rmcstr() in SEARCH.C to create the replacement
 *      meta-character array.  Modified delins() so that it knows
 *      whether or not to make use of the array.  And, put in the
 *      appropriate new structures and variables.
 *    15-sep-87
 *    - added support for Mark Williams C on the Atari ST
 *    - made the MALLOC debugging package only conditional on RAMSIZE
 *    - added code for flagging truncated buffers
 *    23-sep-87
 *    - fixed &RIGHT to return the <arg2> rightmost characters
 *    - fixed a buffer in getval() to be static....things are stabler
 *      now.
 *    - moved all the stack size declarations to after include "estruct.h"
 *      they work a lot better now....... (rather than not at all)
 *    - made Atari ST spawns all work with MWshell
 *    - fixed spawning on the 1040ST under MWC
 *    27-sep-87
 *    - added &exist function to check to see if a named file exist
 *    - added &find function to find a file along the PATH
 *    - added -A switch to run "error.cmd" from command line
 *    - added $gflags to control startup behavior....
 *    03-oct-87
 *    - changed ":c\" to "c:" in epath.h for the AMIGA as suggested
 *      by Tom Edds
 *    - added binary and, or, and xor functions as submited by John Maline
 *      (&band   &bor    and    &bxor)
 *    - added binary not (&bnot) function
 *    - added fixes for gotoline() and nextarg() as submited by David
 *      Dermott
 *    - fixed return value of $curwidth as submitted by David Dermott
 *    - fixed several calls to ldelete() to have a long first argument
 *      (pointed out by David Dermott)
 *    - Fixed a bug in stock() which prevented uppercase FN bindings as
 *      pointed out by many people
 *    - changed dofile() to make sure all executed files don't conflict
 *      with existing buffer names. Took out cludged code in main.c to
 *      handle this problem... this solution is better (suggested by
 *      Don Nash)
 *    05-oct-87
 *    - added in John Gamble's code to allow for a replacement regular
 *      expresion character in MAGIC mode
 *    [note: under MSDOS  we are still TOO BIG!!!!]
 *    - added overwrite-string as a new user callable function, and
 *      lowrite(c) as an internal function for overwriting characters
 *    - added &xlate function to translate strings according to a
 *      translation table
 *    10-oct-87
 *    - added code to allow emacs to clean its own buffers on exit.
 *      useful if emacs is used as a subprogram. Conditional on
 *      the CLEAN definition in estruct.h
 *    14-oct-87
 *    - swallowed very hard and switched to LARGE code/LARGE data model
 *    - packaged and released version 3.9c internally
 *      (MSDOS executables compiled with TURBO C Large model)
 *    16-oct-87
 *    - temporary fix for FUNCTION keys now includes the Meta-O sequence
 *      if VT100 is definined (submited by Jeff Lomicka)
 *    - an VT100 also triggers input.c to force ESC to always
 *      be interpeted as META as well as the currently bound key
 *    - fixed a bug in the VMSVT driver as pointed out by Dave Dermott
 *    - added a size parameter to token() to eliminate problems with
 *      long variable names. (as sugested by Ray Wallace)
 *    18-oct-87
 *    - fixed a bug in the free ram code that did not clear the buffer
 *      flag causing emacs to ask for more confirnmations on the way out.
 *    19-oct-87
 *    - added ^X-$ execute-program call to directly execute a program
 *      without going through a shell... not all environments have this
 *      code completed yet (uses shell-command where not)
 *    [Froze for 3.9d release internally]
 *    28-oct-87
 *    - added code for Atari ST DENSE mode and new bell as submited
 *      by J. C. Benoist
 *    - made extra CR for ST files conditional on ADDCR. This is only
 *      needed to make the desktop happy...and is painful for porting
 *      files (with 2 CR's) elsewhere (Also from J. C. Benoist)
 *    - added optional more intellegent (and larger) close brace
 *      insertion code (also from J. C. Benoist)
 *    4-nov-87
 *    - fixed AZTEC spawning... all MSDOS spawns should work now
 *    - a META key while debugging will turn $debug to false
 *      and continue execution.
 *    [Froze for version 3.9e USENET release]
 *    4-nov-87 Geoff Gibbs
 *    - Fast search using simplified version of Boyer and Moore
 *      Software-Practice and Experience, vol 10, 501-506 (1980).
 *      Mods to scanner() and readpattern(), and added fbound() and
 *      setjtable().  Scanner() should be callable as before, provided
 *      setjtable() has been called first.
 *    13-dec-87
 *    - added a change to the system V termio.c code to solve a keyboard
 *      polling problem, as submited by Karl Lehenbauer
 *    - removed a "static" from the mod95() function declaration
 *      in crypt.c to make MSC happy (by Malcolm MacNiven)
 *    - added code so the new exec routines in spawn.c are working
 *      under MSC (By Malcolm MacNiven)
 *    - fixed the mixed space/tab entabbing bug as suggested
 *      by Michal Jaegermann
 *    - added the missing brace in the VT100 code in getcmd()
 *      (This one was submited by many different people)
 *    - added more intelligent spawning for TURBO C as submitted
 *      by Bob Montante
 *    - added support for the WICAT computers running under the WMCS
 *      operating system as submitted by Bruce Hunsaker
 *    16-dec-87
 *    - re-wrote fillpara(). Its 4 times Faster!!!
 *    - moved M-FNR binding to $readfile ie to make emacs execute
 *      a macro when reading files:
 *        set $readhook "nop"    ;or whetever
 *    18-dec-1987: John M. Gamble
 *    - Made replaces() beep at you and stop if an empty string is
 *      replaced.  This is possible in MAGIC mode, if you pick your
 *      pattern incorrectly.
 *    - Fixed a subtle bug in the new Boyer-Moore routines, which caused
 *      searches to fail occasionally.
 *    19-dec-87
 *    - new search algorithm from Geoff Gibbs, cleaned up by John Gamble.
 *      its over 30 TIMES FASTER!!!! using a simplified Boyer and Moore
 *      pattern search.  This effects all the but MAGIC search commands.
 *    22-dec-87
 *    - narrow-to-region (^X-<) and widen-from-region (^X->) allow you
 *      to make all but a region invisable, thus all global commands
 *      can act on a single region.
 *    - a numeric argument on the select-buffer (^X-b) command makes
 *      that buffer become "invisable"
 *    - M-FNC becomes $cmdhook
 *      M-FNW becomes $wraphook
 *    23-dec-87
 *    - made unmark-buffer (M-~) update the mode lines of all windows
 *      pointing into the unmarked buffer
 *    28-dec-87
 *    - added new prefix MOUS (coded as MS-) for dealing with mice
 *    29-dec-87
 *    - vastly reorginized machine dependant code. Put termio.c and
 *      spawn.c together and then pulled out msdos.c, unix.c, wmcs.c,
 *      atari.c, amigados.c, and vms.c. These are the operating specific
 *      source files now.
 *    30-dec-87
 *    - cleaned up msdos.c. Got rid of two unused spawn functions for
 *      LATTICE. Also removed attempt to lookup SHELL variable to
 *      find the command processer. This is definatly not applicable
 *      here as COMSPEC should always be the name of the reloaded
 *      command processor.
 *    20-jan-87
 *    - added Jeff Lomicka's ST mouse support and added some
 *      appropriate code to input.c to support this.
 *    - added buffer name completion to the select-buffer (^X-B)
 *      command as submitted by Martin Neitzel.
 *    - changed some function names:
 *        abs    =>    absv
 *        atoi    =>    asc_int
 *        ltoi    =>    long_int
 *        setmode =>    setmod
 *        strncpy =>    bytecopy
 *    25-jan-88    By Jeff Lomicka
 *    - Added parsing of keypad keys, LK201 function key sequences, mouse
 *      sequences (VaxStation form and BBN BitGraph form), and the cursor
 *      position report to VMSVT.C.  This will require a change in the way
 *      that VMS users bind functions to their function keys or keypad
 *      keys.  This also defines a defacto-standard for the names of the
 *      numeric keypad keys, based on the VT100 and compatible terminals.
 *    - Added MOUSE.C to DESCRIP.MMS, and changed it to reference ME.OPT,
 *      and to generate ME.EXE.
 *    - Renamed MICROEMACS.OPT to ME.OPT so that the filename would fit
 *      on smaller systems.
 *    - Added capability for copy and paste from the terminal-wide
 *      copy/paste buffer.  This allows copy and paste of the select region
 *      from and to non-cooperating sessions in other windows.  (The
 *      addition of the MOUSE handling routines disables the transparent
 *      use of the VWS copy/paste mechanism.) There may be a bug in the
 *      PASTE section of this code.  On some VWS systems, you may get a
 *      bunch of Hex characters instead of text.  I'm looking in to finding
 *      out what is really supported in the released versions of VWS.  This
 *      code is conditional based on MOUSE & VMSVT.  Code was added to
 *      VMSVT.C.  Added bindings for to ebind.h.  Yank is on ^X^Y.  Copy is
 *      on ^XC.  If MOUSE & VMSVT is true, this binding overides the use of
 *      ^XC for spanwcli.  [This won't stay.. alternative binding?]
 *      Also added definitions for this to efunc.h.
 *    - Added #define of CPM to estruct.h.  It is used in FILE.C.  You
 *      might want to delete it again. [It was deleted..no CPM support]
 *    - Added noshare attributes to all data in many modules.
 *    - Re-introudced XONDATA condition that was in 3.9eJ's TERMIO.C into
 *      VMS.C.  (This was overlooked by Dan in making 3.9g.)
 *    - Appended a ":" to the "MICROEMACS$LIB:" path element in the VMS
 *      portion of EPATH.H.
 *    - Fixed mouse reports from VMSVT.C to correspond to the code in 3.9g.
 *    - In INPUT.C, added VMS to list of systems that generate FN key and
 *      mouse reports with leading 0 bytes.
 *    - In order to accomodate callable editor support, I had to arrange
 *      so that some of the CALLED features are active all of the time,
 *      particularly EXIT HANDLING.  I changed all calls to exit() into
 *      calls to meexit().  There is a great need to divide up exits
 *      between error exits that aren't expected to return, and exits that
 *      just set the exit flag.  Places that didn't expect exit to return
 *      should be changed to return immediately after calling exit, so that
 *      the command loop can catch it and return.  This error handling
 *      business is a real mess right now.
 *    - Re-arranged main() so that most of the guts are in called
 *      routines, so that there can be more than one entry point into the
 *      program.  Note, now, the possiblity of adding recursive-edit as a
 *      function that you can call from a macro.
 *    - Added the universal symbol ME$EDIT to the VMS version as a second
 *      entry point, for use when called by MAIL and NOTES, which use
 *      LIB$FIND_IMAGE_SYMBOL and perform run-time linking with their text
 *      editor.  This stuff works great!
 *    - Changed Atari-ST makefile to link without -VGEM, so that you will
 *      get argc and argv.
 *    - Fixed ST520.C so that screen would be redrawn when we notice that
 *      desk accessories exit, and so that the mouse will be turned off
 *      when exiting into a shell (If text cursor was on, mouse is left
 *      off).
 *    - Changed ST520.C to have bindings for keypad keys, with PF1 "("
 *      key as metac, so that it can be used as GOLD prefix.    Uses GOLDKEY
 *      option in ESTRUCT.H.
 *    26-jan-88    Daniel Lawrence...
 *    - cleaned up coding in main.c
 *    - changed more function names
 *        itoa    =>    int_asc
 *        ltoa    =>    long_asc
 *    27-jan-88
 *    - added terminal initilizer string output to tcap.c as submitted
 *      by Ge' Wiejers
 *    - switched the -A command line switch to be -E the way MWC demands
 *      that it be. Also had to move -E to -C (for Change...)
 *    02-feb-88
 *    - changed META and ^X prefixes to use a new mechinism. Hitting
 *      a prefix stores it as a pending prefix.
 *    05-feb-88
 *    - changed emacs to use ^M for line terminators instead of
 *      ^J. This required LOTS of changes. Now, however, we can
 *      search for and manipulate ^M.
 *    - fixed getcmd() to work again so that describe-key and
 *      interactive binding functions work again.
 *    - added $sterm environmental variable. This hold the current
 *      value of the keystroke needed to terminate search string
 *      requests. The value in here is also automatically reset
 *      any time the meta-prefix is rebound, the the meta-prefix's value
 *    06-feb-88
 *    - fixed bug in stock().. real control characters in command lines
 *      now bind properly
 *    [BBS release of version 3.9i]
 *    23-feb-88
 *    - added buffer name completion to delete-buffer (^XK) and reorginized
 *      code their to gain back 1 K
 *    - added $modeflag to allow us to hide the modelines.
 *    - added $sscroll to allow smooth scrolling... (I don't like this
 *      but there were too many requests for it).
 *    - added $lastmesg to hold last message EMACS wrote out
 *    04-mar-88
 *    - added Alan Phillip's mods to support the VGA adapter on the
 *      IBM PS/2 machines. Modified it a little.
 *    15-mar-88
 *    - Forever twiddling with the startup code, I moved the initialization
 *      of exitflag to main() to allow a startup file to exit EMACS
 *      properly.  Also had to make meexit always return(TRUE) regardless
 *      of the exitstatus. (Ie it always works and doesn't abort the macro)
 *    17-mar-88
 *    - added code to change hard tab size with $tabsize variable
 *    - added binary search to fncmatch()
 *    28-mar-88
 *    - optimized the IBMPC version in TURBO C by supplying mixed memory
 *      mode information (NEAR and PASCAL). The executable is down to
 *      89K..but remember to name the code segment (from the options menu)
 *    1-apr-88
 *    - added remove-mark (^X<space>) to allow you to unset the mark
 *      in the current window.
 *    8-apr-88
 *    - Lots of twiddling with the mixed memory model TURBOC IBM-PC
 *      version... its 87K long now and fairly stable
 *    - changed behavior of CMODE when inserting blank lines
 *    - tightened stack usage from 32K to 20K
 *    9-apr-88
 *    - added new cinsert(). blank lines no longer confuse the CMODE
 *      indentation. Trailing white space is deleted when newline is
 *      hit in CMODE.
 *    12-apr-88
 *    - fixed long standing bug in query-replace-string. When the line the
 *      point originally starts on is extended (thus re-malloced) a '.',
 *      aborting the replace and returning to the original replace had
 *      locked things up. no more.
 *    07-may-88
 *    - fixed bug in narrow() ... it works everywhere now.
 *    [BBS release of 3.9n]
 *    3-june-88
 *    - removed restriction against deleting invisable buffers
 *    - a lot of little fixes suggested by Dave Tweten
 *    10-jun-88
 *    - added "safe save"ing as coded by Suresh Konda.
 *      (when writing a file to disk, it writes it to a temporary file,
 *       deletes the original and renames the temp file)
 *    - added $ssave flag to enable or disable safe file saving
 *    12-jun-88
 *    - added automatic horizontal window scrolling.    $hscroll (default
 *      is TRUE) controls if it is enabled. $fcol is the current first
 *      column of window in screen column one.  $hjump determines the
 *      number of columns scrolled at a time.
 *    - changed version number to 3.9o
 *    22-jun-88
 *    - made binary searches start from 0 instead of one... EMACS can
 *      find the first of many lists again.
 *    - more debugging things.  Added the dump-variable command which
 *      creates a buffer (like list-buffers does) with all the environment
 *      and user variables and their values.    Also the display (^XG)
 *      command prompts and lists the value of a variable.  These are
 *      both conditional on the DEBUGM symbol in estruct.h
 *    1-jul-88
 *    - fixed a bug in showcpos() which did not report the proper value
 *      for the current character when issued at the end of the file
 *    [Released internally as 3.9p]
 *    3-aug-88
 *    - changed keyname in stock() in bind.c to unsigned char for
 *      compilers that don't default. This allows more arbitrary
 *      rebinding. (submitor: David Sears)
 *    12-aug-88
 *    - changed wrap-word to force $fcol to 0
 *    - changed fill-paragraph (M-Q) to force $fcol to 0
 *    - added -i command line switch to initialize a variable's value
 *      for example:    emacs -i$sres VGA
 *    26-aug-88
 *    - changed code in updateline() in display.c to remove reliance
 *      on well behaved pointer subtraction (submitted by Kenneth Sloan)
 *    - fixed potential bug in fileio.c in ffgetline()
 *      (submitted by John Owens)
 *    6-sep-88
 *    - &right and &mid now check their arguments so the bytecopy can not
 *      start past the end of the string.
 *    - added $writehook to execute macroes when writing files
 *    - added $exbhook to execute macro when exiting an old buffer
 *    - added $bufhook to execute macro when entering a new buffer
 *    14-sep-88
 *    - asc_int() now ignores trailing non-digits
 *    15-sep-88
 *    - added &trim function to trim whitespace off a variable
 *    - changed message "Out of memory while inserting string" to
 *      "Can not insert string" as this error can result when the
 *      current buffer is in VIEW mode as well.
 *    - made trim-line, entab-line, and detab-line work on the
 *      current region if they have no arguments.  Also added alias
 *      trim-region, entab-region and detab-region.  The old names
 *      will hang about for a version, then dissapear.  I like the
 *      new functionality much better.
 *    25-sep-88
 *    - Inserted the macros isletter(), isuppper(), islower(), and
 *      CHCASE() whereever appropriate, replacing explicit character
 *      comparisons.    When DIACRIT is set to one, they become functions
 *      and know about the extended ascii character set.  Functions right
 *      now are in for MSDOS.C - other machines to follow.  From J. Gamble.
 *    26-sep-88
 *    - moved all text constants out to a language specific header file
 *      and left an english version of the constant in a remark at its
 *      occurence.
 *    - added $language to return the language of the current version
 *    - added elang.h to call the proper language specific module
 *    2-oct-88
 *    - removed DIACRIT conditional. Its there all the time now. Ripped
 *      the old code, and replaced it with a upcase[] and lowcase[]
 *      table.  Functions to manipulate it are now in new source file
 *      char.c and can be made conditional on system and language.
 *      Added table for extended MSDOS modeled after John Gamble's
 *      code.
 *    5-oct-88
 *    - got rid of CHCASE()..[except in the MAGIC mode search code]
 *      I ALWAYS force to upper or lower, and never simply swap.  They
 *      are now uppercase() and lowercase() in the new char.c source file.
 *    7-oct-88
 *    - added all the needed code to use TERMCAP on UNIX to interpret
 *      function and cursor keys.  A rather slimy trick involving
 *      the key timing is used, and this makes keyboard macroes
 *      a little dicy....
 *    - added the DIACRIT compilation flag back for people who
 *      want more speed in MAGIC mode.
 *    10-oct-88
 *    - as suggested by Michael Andrews, when the current buffer is
 *      in view mode, don't preallocate expansion room in new lines.
 *      (ie we aren't editing them anyway!)
 *    - added Microsoft Mouse drive... went very well. It all appears
 *      to work, just like the Atari ST mouse driver.
 *    11-oct-88
 *    - recieved and tested german.h header file from Martin Neitzel
 *      (unido!sigserv![e-mail])
 *    15-oct-88
 *    - recieved and tested dutch.h header file from Paul De Bra
 *      ([e-mail])
 *    - fixed a lot of mouse movement problems.  Dragging a mode line
 *      sideways horizontally scrolls a it's window.  Fixed positioning
 *      problems with scrolled and extended lines.
 *    - added $msflag to turn the mouse off
 *    - added $diagflag.  When set to FALSE, no diagonal movement is
 *      possible.  Vertical movement has precidence, but an explicit
 *      horizontal drag still works.
 *    - grabbing and dragging the last char of the command line allows
 *      you to resize the editing screen.  This should be tied into
 *      various windowing systems later.
 *    - write mouse-region-(down/up). See the emacs reference docs on the
 *      exact behavior of these.
 *    - deleted the old mouse-(kill/yank)-(up/down). They are
 *      redundant now, and don't work as well as mouse-region-*.
 *    2-nov-88    [changes submitted by Allen Pratt from ATARI]
 *    - created DIRSEPSTR and DIRSEPCHAR definitions for directory seperators
 *    - added TTflush in bindtokey() to force space out to terminal after
 *      binding name.
 *    - fixed a pointer casting problem in display.c involving pointer subtraction
 *    - removed the cursormove() from the beginning of mlwrite() so
 *      the cursor need not jump to the command line if the fisplay
 *      is disabled by setting $discmd to FALSE.
 *    - added >c to get a emacs command sequence and return it as
 *      a bindable string
 *    - changed scrnextup -> nextup, scrnextdn -> nextdown, and
 *      mlreplyt -> mltreply to make short symbol compilers happy.
 *    - added "print" as a synonim to "write-message".
 *    - added "source" as a synonim to "execute-file".
 *    - added a M-^X binding to the execute-command-line command
 *    4-nov-88
 *    - changed $tabsize to $hardtab. Added $softab as the current
 *      softtab size (previously only changable by the ^I (handle-tab)
 *      command.
 *    - fixed various problems in reglines() and made ^X^D (detab-region)
 *      and ^X^E (entab-region) use the current hard tab setting.
 *    - execute-command-line (M-^X) when executed within a macro line
 *      (which sounds redundent) will force all of the arguments of
 *      the executed command to be taken interactivly.  I needed this
 *      for the new macro to allow mouse functionality on the
 *      function key window.
 *    - taking Michael Andrew's suggestion to its conclusion, we no longer
 *      allocate any extra space except when inserting.  This has
 *      substantially decreased the memory usage.  Note that when
 *      we must explicitly set l_used to the proper amount since lalloc()
 *      is not responcible for the rounding up.
 *    - arranged to allow getstring() to return a NULL result.  Aborting
 *      out of an interactive prompt now will properly terminate a macro.
 *    [Released the 3.10 BETA test version...yes the ATARI version is broke]
 *    24-nov-88
 *    - fixed system V input char HOG problems as submitted by
 *      Kjartan R. Gudmundsson. Also eliminated some other 7 bit filters
 *      in unix.c at the same time.
 *    - reading function keys into table has been fixed in TCAP.C.  It will
 *      no longer attempt to strcpy NULL pointers.
 *    1-dec-88
 *    - multiple marks are now implemented. (What a task...). Set-mark
 *      (M-<space>), remove-mark (^X<space>) and exchange-point-and-mark
 *      (^X^X) all take a numeric argument from 0 to NMARKS-1 (9 now).
 *    2-dec-88
 *    - added goto-mark (M-^G) which moves the point to the requested mark.
 *    - fixed some VMS things that Curtis pointed out...
 *    - fixed bug in crypt() algorith!!!! This works properly now.  I had
 *      to add a $oldcrypt environment variable to trigger the broken
 *      behavior so people could decrypt their old files.  I will probably
 *      have to live with this.....
 *    15-dec-88
 *    - added end-of-word command to advance just past the end of a word.
 *    20-dec-88
 *    - added definitions for SUN's OS and SCO XENIX to allow us to use
 *      specific calls in those OSs for waiting and timing.
 *    - merged in XTCAP.C as submitted by Guy Turcotte into tcap.c.  This
 *      mirrors the BSD 4.3 changes for function keys for the SCO XENIX
 *      and SUN OS versions
 *    14-jan-89
 *    - added $region as a read only variable (max 128 chars) of the
 *      current region (as suggested by Allan Pratt)
 *    - changed KEYTAB structure to allow us to bind user macroes
 *      (buffers) to keys as well as C functions. Lots of changes
 *      for this.
 *    18-jan-89
 *    - finished changes for the new KEYTAB structure.
 *    - modified describe-bindings to display the bound macroes.
 *    - added arguments to nullproc() in main.c (BUG FIX!)
 *    - tried (and succeeded) in defining the pascal keyword
 *      for MSDOS & TURBO. A 2k reduction in the executable was nice.
 *    - added macro-to-key (^X^K) function to bind a macro to a key.
 *    19-jan-89
 *    - made numeric arguments to keys bound to macroes repeat those
 *      macroes n times.
 *    - modified docmd() to look for a macro name if it could not find
 *      a function name. Again a numeric leadin implies repitition.
 *    - added machine code execpr() function to the IBMPC version
 *      because under NOVELL Netware, the DOS 4B exec call does not
 *      preserve the stack on exit... thus execprog() would die.  This
 *      requires that you add execpr.obj to the make and link files!
 *      There is a symbol (NOVELL) in estruct.h to control this code
 *      being included.
 *    24-jan-89
 *    - various bug fixes and type fixes as suggested by the high C
 *      compiler on the IBM-RT
 *    1-feb-89
 *    - changed the fgetc() in unix.c to a read() under V7 and BSD so
 *      the time dependant function key checking works.
 *    - added a support for Hewlet Packard's UNIX system which
 *      is a System V with BSD 4.3 enhancements.  This is controled
 *      by the HPUX symbol in estruct.h.
 *    5-feb-89
 *    - modified mouse-region-up so right clicking down on a modeline and
 *      then releasing closes that window
 *    12-feb-89
 *    - Goaded onward by file completion code submitted by Fuyau Lin, all
 *      the completion code has been re-written and layered properly.
 *      Any OS specific driver need to now supply getffile() and
 *      getnfile() to supply a completion file list, or these can
 *      return NULL on systems where this is not possible. All this code
 *      is conditional on the COMPLET symbol in estruct.h.
 *    17-mar-89
 *    - system V code from April 1989 "C Users Journal" installed in
 *      UNIX.C. Hope this puts that problem to rest.
 *    - Jeff Lomicka fixed a lot of mousing bugs in ST520.c
 *    - Re-wrote AMIGADOS.C.  This should work properly with INTUITION
 *      and lots of windowing (resizing, mousing, etc.)
 *    - more additions for the DATA GENERAL from Doug Rady. (read
 *      the history in aosvs.c for details).
 *    - orginized the NOSHARE, VIOD and CONST keywords better.
 *    - A lot of general cleanup.
 *    [Released as version 3.10 to the world]
 *    05-may-89
 *    - installed the BRICKS revsion control system (from DATALIGHT)
 *      on my PC developmental machine.  This should make diffs possible.
 *      The installation was convoluted to to brick's inibility to
 *      use subdirectories, and implemented through a much more
 *      complex makefile.
 *    - fixed a missing structure element in line 1230 of eval.c
 *    - set attribute to clear screen to 07 in ibmeeop.  This fixes
 *      a long standing bug involving not seeing the modeline.
 *    16-may-88
 *    - a bad character in UNIX.C's code for the HPUX is fixed
 *    - a couple of header problems for HPUX fixed
 *    - a bug in EVAL.C comparing var names past 10 chars is fixed
 *    - added Dan Corkill's ISEARCH mods (see ISEARCH.C) Had
 *      to fix them to allow function keys at the end of an isearch.
 *    22-may-89 John Gamble
 *    - added $SEARCHTYPE var to determine where searches terminate.
 *        0 = forward: after string, backward: at beg of string
 *        1 = always at beginning of string
 *        2 = always character past end of string
 *      added code and vars all around for this
 *    28-may-89
 *    - finished fixing ISEARCH to properly allow function keys and
 *      mouse movement to terminate the ISEARCH.
 *    28-may-89 John Gamble
 *    - Code finally added to handle the $SEARCHPNT (nee' $SEARCHTYPE)
 *      variable.  Frankly, i think its pretty sloppy, and should
 *      be replaced by a separate function to deal with point positions.
 *      Will change it later.
 *    7-jul-89 John Gamble
 *    - A far more elegant way of dealing with $SEARCHPNT is present,
 *      more efficient in space also.  Didn't need the above mentioned
 *      point function.  Altered ISEARCH.C code to use new calling
 *      parameters in scan routines.
 *    - Got started with group structure in MAGIC mode, with alterations
 *      present in estruct.h and search.c
 *    15-jul-89 John Gamble
 *    - added $disphigh environment variable to control the escaped
 *      display of high bit set ascii characters
 *    05-aug-89 Daniel Lawrence
 *    - added to lines to lbound() so a forward search will no longer
 *      wrap around the end of the buffer if the point was at the end.
 *    - widen-from-region (^X>) preserves the point and marks if they
 *      were at the end of the fragment, instead of moving them to
 *      the end of the buffer.
 *    - fixed bug in comp_file() to allow up to 128 char files specs
 *      instead of 32 chars.
 *    - patched some bugs in the TIPC version.  It runs again, but
 *      without a mouse and color and reverse video.  The TIPC I had
 *      to test on was a weird mono one....
 *    - released 3.10a to the BBS for TIPC users
 *    05-aug-89 John Gamble
 *    - refolding and shoving a lot has managed to knock about 300
 *      bytes of code out of search.c and isearch.c.  Also the some of
 *      the various commands in an isearch now shadow their bigger
 *      counterparts.
 *    - fixed the tab bug in entab-line (^X-^E) which munged lines.
 *    15-aug-89 Daniel Lawrnece
 *    - added append-file (^X^A) command to append a buffer on the
 *      end of a file
 *    [released 3.10b to Krannert.....]
 *    20-aug-89 Daniel Lawrence
 *    - The quote character is now treated as the abort and universal-
 *      argument characters are: only one key may be bound to it at
 *      a time.
 *    9-sep-89
 *    - a bug in msdos.c prevented the proper binding of ALT-0 on the
 *      IBMPC. Fixed this as pointed out by Rik Faith.
 *    17-sep-89 John M. Gamble
 *    - Isearch now understands alternatively bound keys.
 *      One change had to be made to ebind.h and input.c, to handle
 *      the delete-previous-character command.  The delete character
 *      is now represented internally as CNTL|'?', instead of 0x7F.
 *      Changes made to handle this are in ebind.h and input.c.
 *    16-dec-89
 *     - Incorporated Kevin Mitchell's VMS improvements.  Using the
 *       native RMS file I/O, and native memory memory routines
 *       GREATLY speeds up file and buffer manipulation.
 *    17-dec-89
 *    - updated the HP150.C file to work with the new style I/O layers.
 *      hp150 version now works properly.
 *    25-jan-90
 *    - dumped a lot of the old choice symbols in estruct.h for some
 *      things which have either never been used, or have clearly
 *      superior versions now.
 *    - removed the WORDPRO and AEDIT symbols.... all this code is
 *      always in now.  (it never made much of a size difference anyway)
 *    - modified sources to allow them to use new ANSI style prototypes.
 *      (this was a lot of work....)
 *    - in the process, fixed bug where EMACS probably grew confused
 *      when setting $curchar to a newline.
 *    26-jan-90
 *    - replaced old file completion code with version by Michael J. Arena
 *      It allows us to partially complete directory names on UNIX.
 *    - modified getffile in MSDOS.C to return directory names as well
 *      so it can work with the above mod.  I need to do this mod on
 *      all OSs which will support it.
 *    - added support for the Supermax UNIX system as submitted by
 *      Michael Hillerstrom.
 *    - fixed a couple of OS2 bugs having to do with key input as submitted
 *      by Sugih Jamin
 *    - fixed three bugs posted by Kieth Jones (in display.c and eval.c)
 *    - let the TURBO C MSDOS version use the bios instead of DOS for
 *      keybord input as submitted by David R. Kohr.  This should solve
 *      problems with TSRs like Sidekick that break rules.
 *    - fixed a bug in MSDOS.C's getffile involving how the filename was
 *      parsed.  Paths including ".." now can expand properly.
 *    [Released version 3.10e to USENET]
 *    - changed version number to 3.10f
 *    15-feb-90
 *    - added $lterm variable to allow emacs to write non-standard line
 *      terminators on output.  Set to "" it uses standard terminators.
 *    - forced ffgetline() to trim trailing line terminators on reading
 *      this allows us to read strange files more robustly.
 *    - removed the ADDCR option as the var above can do it
 *    17-mar-90
 *    - John Gamble found and fixed a bug in the binding code erroneously
 *      searching for a particular empty slot.
 *    22-mar-90
 *    - changed line buffer allocation scheme during file reading to
 *      use realloc() and always double the buffer size.  Much faster
 *      on long line reads.
 *    01-may-90
 *    - added code to allow SUN verion to work properly
 *    - added .xlk style file locking for unix systems
 *    10-may-90
 *    - added NEC 9801 hardware driver.  There is no background color
 *      implimented yet as this will involve using the graphic planes
 *      to simulate a backgound color.
 *    25-may-90
 *    - added DBCS (Double Byte Character Set) symbol to estruct.h and
 *      also much conditional code to handle display and editing of
 *      DBCS chars.  This code is active in the NEC version, using
 *      japanese KANJI characters.
 *    - added REP (replace) mode. Very similar to OVER mode except
 *      tabs and 2 byte characters are handled differently.
 *    6-jun-90
 *    - modified ansi.c into fmr.c for the Fujitsu FMR-70 series
 *      msdos machines.  Extensive modifications to msdos.c were
 *      needed to accomodate this machine.
 *    16-jun-90
 *    - modified swbuffer() to not check locks on an inactive buffer
 *      in view mode.  This allows the -v switch to work from the
 *      command line on a file whose directory the user has no
 *      write access to.
 *    28-jun-90
 *    - added background colors to the FMR driver utilizing the
 *      graphics planes via the GDS driver.
 *    30-jun-90
 *    - added $wchars, a list of characters considered "in a word".
 *      An empty value sets this to its default of alphas, numbers
 *      and the underscore (_) character.
 *    5-jul-90
 *    - re-arranging code to vector all pop up windows through on
 *      function for display.
 *    - fixed bug in positioning of file name in buffer list
 *    6-jul-90
 *    - added ability to pop up temporary windows.  Environment variable
 *      $popval gives the old behavior when FALSE and the new behavior
 *      when TRUE.
 *    - added pop-buffer function to allow user to pop up the contents
 *      of a buffer.
 *    27-jul-90
 *    - fixed up the OS2 code back into working.  Wrote getffile()
 *      and getnfile() to allow it file name completion.
 *    27-jul-90 John M. Gamble
 *     - Magic mode characters '+' and '?' added, respectively meaning
 *    "one to many" and "zero to one (or, optional)".
 *    12-oct-90
 *    - A BAD bug in vteeol() hung the machine during the redraw.  Vtcol
 *    was not getting incremented when the screen was scrolled horizontally.
 *    26-nov-90
 *    - conditionalized code in MSDOS.C using the BIOS to not be used when
 *    compiled for the HP150.  (It's bios is different, of course)
 *    15-jan-91
 *    - in linstr() made an non-positive number of inserted characters
 *      illegal, causing the linstr to return FALSE on negative and
 *      TRUE on zero... but not changing the text
 *    15-jan-91
 *    - rewrote dolock.c to generalize it. it now supports MSDOS and SUN
 *      the SUN code should work on other UNIXs, but needs confirmation
 *    17-jan-91  John Gamble
 *    - removed references to DIACRIT
 *    - added the $yankpnt variable.
 *    21-jan-91  Daniel Lawrence
 *    - adding OS2 support for file locking
 *    07-mar-91
 *    - added the concepts of SCREENs.  Each screen is a separate list
 *      of windows which overlay on text based systems.
 *
 *    New commands:
 *      next-screen        (A-N) switch to the following screen
 *      previous-screen    (A-P) switch to the previous screen
 *      find-screen        (A-F) switch or create a named screen
 *      delete-screen        (A-D) delete the named screen
 *      list-screens        (A-B) how list of screens
 *
 *    New variables:
 *      $scrname        name of the current screen
 *      $scrnum        ordinal number of the current screen
 *
 *    Most of the code for this is in the new source file SCREEN.C
 *
 *    11-mar-91    Code from or suggested by Michael C. Andrews
 *    - getstring() now accepts ^K to return a non-default empty
 *      result. (to allow for NULL replace strings!)
 *    - added indent-region [M-)] and undent-region [M-(]
 *    - added &ISNum function to test variables for being numeric
 *    - added $curwind and $numwind to give the current ordinal and total
 *      number of windows on the current screen
 *    12-mar-91    Daniel Lawrence
 *    - checked and fixed code for IBMPC MicroSoft C 5 and 6 compilers
 *    15-mar-91    Curtis Smith
 *    - masked the number generated by ernd in writeout() to limit it
 *      to 5 digits so that MPE won't barf on a too long file name
 *      for the temporary file
 *    19-mar-91    Daniel Lawrence
 *    - added code to parse drive letters to dolock()/undolock()
 *      MSDOS is happier.
 *    - changed search order of files to look in current directory
 *      before HOME and PATH dirs.
 *    24-mar-91
 *    - command file names default to a .cmd extention from the command
 *      line and from the source command.
 *    [released BETA version 3.11]
 *    02-apr-91
 *    - neglected to decrement buffer use counts in free_screen()
 *      These are now fixed, so delete-screen is again safe.
 *    19-apr-91 John M. Gamble
 *    - Made a couple of functions, cclmake() in particular, more efficient.
 *      Saved a hundred bytes or so, which were immediately used up by:
 *    - Groups!  Groups are now available in MAGIC mode! (hurrah).
 *    - Fixed bug where $match would get set with the wrong characters
 *      if searching backwards.
 *    - also declared as VOID the VOID functions in search.c.  Should
 *      get nattered at less often now.
 *    23-apr-91 Daniel Lawrence
 *    - namebuffer() was only updating the current modeline. It needed to
 *      update all of them in case the current buffer was in multiple
 *      windows. This bug was pointed out by Martin Shultz.
 *    - added code from Floyd Davidson for new backward kill behavior. This
 *      is under the NEWKILLB symbol and is for evaluation.
 *    24-apr-91
 *    - John Gamble points out that local variable "ap" in mlwrite() can
 *      not be register type. Fixed this.
 *    - as reported by Martin Shultz, tabs caused problems in OVERwrite
 *      mode since the logic for determining to delete or not was based
 *      on offset into the line rather than column. Preceding tabs
 *      confused this. I changed the offset reference (in main.c) to a
 *      reference to the getccol() function and all is well.
 *    - Risto Kankkenun pointed out a problem in the input handling of
 *      any completion command... it did not handle function keys well,
 *      and blocked some normal keys from being used. Inputing an
 *      extended character in complete() and then translating it to a
 *      standard ascii char let us correct this.
 *    - Risto also points out a one character difference between word
 *      wrapping and paragraph filling. Changed a couple of >= to > in
 *      reform() in word.c to correct this.
 *    27-apr-91  John Gamble
 *    - Oops.  In changing the closure code, so that groups and closure
 *      could be used together, i broke closure.  Argh.  Fixed now.
 *    - Added the &GROUP function, so that macro writers could get at
 *      the substrings matched by groups in a MAGIC search.
 *    - Since $yankpnt is a Boolean type now, changed its name to
 *      $yankflag.
 *    - Altered the broadcast message interceptor code in VMS.C.  Instead
 *      of using a %variable to hold the message, which was not large
 *      enough, the message(s) are stashed away in a buffer.  Added a
 *      global boolean variable pending_msg, which Dan will use to notify
 *      the user of an intercepted message.
 *    1-may-91  Daniel Lawrence
 *    - the backward kill code was very interesting.... but did not update
 *      the $kill variable (via getkill() in eval.c) and caused all sorts
 *      of interesting sideffects when the clear kill buffer code was not
 *      updated either. I refigured the algorithm to use the current kill
 *      blocks, growing them backwards as needed. Recoding this, it all
 *      works properly now, allowing negative kills and proper behavior
 *      when mixing various consective forward and backward kills. This
 *      new code is smaller and involved less changes.
 *    2-may-91
 *    - changed some WFHARDs to WFMOVEs in basic.c for gotobob() and
 *      gotoeob() as suggested by Risto Kankkunen
 *    - removed a call to turn break off under MSDOS in ibmkopen()
 *      in ibmpc.c to answer a observation from John A Steele
 *    - changed some file names. ATARI.C => TOS.C   ST520.C => ST52.C
 *      to more accurately reflect the OS and screen code for the ATARI
 *    - made a lot of changes in TOS.C as specified by Allan Pratt
 *    - fixed setkey() to not choke on undefined functions
 *    11-jun-91
 *    - added in support for LATIN as submited by Anthony Appleyard
 *    - cause the prompt for search patterns to show the current search
 *      terminator
 *    23-jun-91
 *    - in BASIC.C in gotobop/eop() changed some offests to zero constants
 *      speeding things up.
 *    - also added $scribe so I can add in scribe specific formatting
 *      features, like deciding @commands at the begining of lines delimit
 *      paragraphs.
 *    26-jun-91    John Gamble
 *    - added check for isearch and risearch binding in the incremental
 *      search commands, as suggested by ???.
 *    - Put in new text strings from search.c into the <language>.h files.
 *    - Removed the code in BIND.C which checked for the .rc file in the
 *      current directory before checking HOME.  This was dangerous in a
 *      multi-user environment.  Change the HOME variable if you want to
 *      use a different set of .rc and .cmd files.
 *    10-jun-91    Daniel Lawrence
 *    - dumped $scribe. Instead we are adding features to handle any
 *      formatter of that style. $fmtlead lists all formatter command
 *      leadin characters. $paralead lists all paragraph start charaters.
 *    - changed a check in setvar() to allow an interactive input value
 *      to be just the <NL>, allowing you now to interactively set
 *      a variable to being empty. ^G still aborts the set.
 *    17-jun-91
 *    - a missing parenthesis in a conditional in cinsert() sometimes
 *      caused a problem when strinking return in CMODE
 *    24-jul-91
 *    - changed a write in ttflush() to go to stdout instead of stdin
 *    18-aug-91
 *    - replaced tipc.c driver and made minor accomodations to many files
 *      for support of memory mapped TIPC driver under Zortech C as supplied
 *      by Ron Lepine
 *    - added code to msdos and OS/2 to recognize F11, F12 and application
 *      keypad as seperate, bindable keys. Submitted by Jon Saxton
 *    2-Sep-91
 *    - made some minor changes for OS/2 submitted by John Ladwig
 *    4-Sep-91
 *    - made a lot of adjustments to the new keyboard.c file for recognizing
 *      IBMPC extended keys. I think most of its keys are now mapped in all
 *      modes which the BIOS will recognize under both MSDOS and OS/2.
 *    6-Sep-91 John M. Gamble
 *    - changed the outer while loop of scanner() to a if/do-while
 *      combination.  This allowed the removal from the inner loop of an if
 *      statement that was returning a constant value.  Speeds up searches
 *      noticably.
 *    - reverse searching in fbound() was using matchlen as a jump increment.
 *      This causes reverse-search to fail if we had just removed MAGIC mode,
 *      since matchlen may be different from the pattern length, causing the
 *      search to fail.  Changed to (patlenadd + 1).
 *    - Code which stored away the previous match before saving the current
 *      match is moved to the replaces() function where it belongs.  Less
 *      work for simple searches.  Also changed the free()/malloc()
 *      combinations to simple realloc() calls - much neater.
 *    - Putting the "next character" calls in the correct place in amatch()
 *      meant that i could get rid of all the special checking for BOL and
 *      EOL characters.  Saved much code space that way.
 *    - Fixed the fence flashing bug where the cursor failed to flash back
 *      to a fence which was the first character in a buffer.  Simple matter
 *      of moving the forward/backward cursor calls in the right place.
 *    - New function regtostr() is what is called now to save matches, group
 *      matches, set $region, etc.  Space saver, faster.
 *    7-Sep-91 John M. Gamble
 *    - Changed the realloc()s back to free()/malloc() combinations.
 *      There are still compilers out there who do not have ANSI C
 *      functions, like certain UNIX systems, which used to be on the
 *      cutting edge, but are now warts.  Arghhh.
 *    - Fixed a group length problem, when matchlen was getting added
 *      more than once (closure again).  New group_length array fixes
 *      that.
 *    12-Sep-91 Daniel Lawrence
 *    - fixed setting of $cbflags, changing mask from BFCHG&BFINVS to
 *      BFCHG|BFINVS, letting it work as suggested by John Gamble
 *    14-Sep-91
 *    - fixed a bug in the mouse handling in mouseline() which prevented
 *      us from positioning the mouse on the last line of the window when
 *      $modeflag was set to FALSE
 *    15-Sep-91
 *    - In frustration from the new help system crashing and leaving me
 *      unable to comunicate visibly with the command like, emacs now
 *      sets $discmd and $disinp to TRUE whenever it goes to fetch an
 *      interactive command. Delete the assignment in execloop() if this
 *      gets in the way
 *    21-Sep-91
 *    - the new code for decoding the AT keyboard fails real poorly on an
 *      XT or earlier style machine. When ATKBD is enabled, if the call
 *      fails the first time, emacs automatically switched to using the
 *      old style (not that old really) BIOS calls for input.
 *    5-Oct-91
 *    - two new variables, $orgrow and $orgcol, and two new function
 *      change-screen-row and change-screen-column, all you to change
 *      the upper left corner of emacs' screen on the physical screen.
 *      You must resize the screen smaller than default before this
 *      will work.
 *    - screen resolution changes on the IBMPC force the screen back
 *      to the upper left corner. This may change in the future.
 *    8-Oct-91
 *    - size and position of screen maintained in the SCREEN structure
 *      so switching screen resets these.
 *    - Mousing code now switches screens if mouse is used outside of
 *      current screen.
 *    9-Oct-91
 *    - Switching screen deactivates modeline of outgoing screen.
 *    - Screen list now orginized front->back instead of alphabetically
 *    - dumped $scrnum as it changes dynamically and is not very usefull
 *    - replaces next-screen and previous-screen with cycle-screens (A-C)
 *      which brings the rearmost screen to front. Mousing to a window
 *      now operates in front to back order! screen.c is smaller!
 *    11-Oct-91
 *    - added logic to refresh screens when sizing down or moving screen
 *    - added $deskcolor var to hold color desktop should be cleared to
 *    - added TERM structure entry .t_clrdesk as a ptr to function to
 *      clear the desktop when redrawing windows
 *    15-Oct-91
 *    - added code to ibmpc version to properly track screen resolution
 *      changes. If a screen is the size of the desktop at resolution change
 *      time, it is resized to the new desktop size.
 *    16-Oct-91
 *    - noticed the wrong character set when returning from VGA12 mode
 *      on the ibmpc. Added code to fix this in egaclose() in ibmpc.c
 *    21-oct-91
 *    - added code in IBMPC output routine to interpret char 7 as a beep
 *    25-oct-91
 *    - added ability of macro to suppress screen redraw by setting second
 *      bit in $gflags... like after a shell-command that doesn't output
 *    30-oct-91
 *    - added ability to set any $...hook variable to a named procedure
 *      as well as a built in command.
 *    - modified the standard startup file EMACS.RC to use named procedures
 *      rather than numbered macroes for all its internal functions.
 *    - Modified manual to emphisize the use of named procedures rather
 *      than the execute-macro-<n> commands which I am trying to phase out.
 *    31-oct-91
 *    [RELEASED version 3.11 for general distribution]
 */

history()

{
    /* this is here to keep compilers from complaining... it's not needed */
}