GLOBAL VARIABLES

    These variables are defined for one reason or another and used
    internally. None of these variables have to be initialized (see
    insertmode.) They are mainly used to return extra values found in
    certain functions or needed globally by other functions.

    Date variables

         char *Days[7] = { "Sunday","Monday","Tuesday","Wednesday",
                           "Thursday","Friday","Saturday" };
         char *Months[12] = { "January","February","March","April",
                              "May","June","July","August",
                              "September","October","November",
                              "December" };
         char *MonthAbbr[12] = { "Jan","Feb","Mar","Apr","May",
                                 "Jun","Jul","Aug","Sep","Oct",
                                 "Nov","Dec" };
         int daylist[13] = { 0, 31, 59, 90, 120, 151, 181, 212,
                             243, 273, 304, 334, 365 };

    Note: daylist is a list of the day number of the year at the end
          of each month (i.e. April 1st is the 91st (Mar 31 = 90, +1)
          day of the year.)


    Keyboard variables

         boolean key_extended;    /* TRUE if special key pressed,
                                     i.e. Alt-X, etc. */
         int key_status;          /* shift key status byte */

    Note:  these variables are set by getk(), and are checked by
           many other keyboard routines.

         boolean insertmode;      /* insert or overwrite mode? */

    Note:  This variable is used internally by getstr() and getget().
           Although getget() initializes this variable, getstr() does
           NOT. You MUST set insertmode to TRUE or FALSE before
           calling getstr() or unpredictable results may occur. Upon
           completion of this function, testing this variable will
           determine the input mode last used. Future versions will
           default insertmode to some value if it has not been set.

    Menu variables:

         int litebarerrno;
         int popuperrno;


    Mouse variables:

         int _mouse1, _mouse2, _mouse3, _mouse4;

    Multitasking variables

         char _dvmajor;
         char _dvminor;

    Real (simulated FP) variables:

         int _r_minpre, _r_maxpre;
         boolean _r_maximum = FALSE;
         int _rmatherror;

    State/Zip code variables:

         const char *States[]
         const char *StateName[]
         const long ZipMin[]
         const long ZipMax[]

    TCHK version variables

         unsigned int _TCHKversion = 0x0210;
         unsigned char _TCHKmajor = 2;
         unsigned char _TCHKminor = 10;
         char *_TCHKdate = "06/06/89";
         char *_TCHK = "TCHK is Copyright (C) 1988,1989 by Howard
                        Kapustein.  All rights reserved.";


    Video variables

         FRAMES: see video.h for frame[] declarations.

         const char emptystring[] = "               ";

         Note: Do NOT alter this variable. emptystring[] is defined
               as a string of 15 spaces and is used internally by
               several functions. Altering this function can lead to
               wildly unpredictable results.

         byte char_attribute;

         Note: This variable is used by many output functions to set
               the attribute byte. For functions such as putstr() you
               can either call set_color() with the attribute desired
               or declare char_attribute as an extern and then set it
               yourself.

         int _shadowstyle =  SHADOW_B | SHADOW_BR | SHADOW_R;
         char _shadowchar = '#';
         char _shadowcolor = LBLACK | B_BLACK;