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Text File | 1994-04-26 | 31.1 KB | 730 lines

`co(4,7);─────────────────────────── /// Structures/Globals ───────────────────────────`color(); ┌──────────────────────────────────────────────────────────────────────────┐ │ `keyword(RECT,/// RECT); `keyword(WINDOW,/// WINDOW); │ │ `keyword(EVENT,/// EVENT); `keyword(M_RESET,/// M_RESET); │ │ `keyword(M_LOC,/// M_LOC); `keyword(M_MOVE,/// M_MOVE); │ │ `keyword(PRINT,/// PRINT); `keyword(MENU,/// MENU); │ │ `keyword(Video Globals,/// Video Globals); `keyword(Event Globals,/// Event Globals); │ │ `keyword(Default Attributes,/// Default Attributes); `keyword(Cursor Globals,/// Cursor Globals); │ │ `keyword(DesqView Globals,/// DesqView Globals); `keyword(Manager Globals,/// Manager Globals); │ │ `keyword(Function Globals,/// Function Globals); `keyword(Printer Globals,/// Printer Globals); │ │ `keyword(Timer Globals,/// Timer Globals); `keyword(Graphics Globals,/// Graphics Globals); │ │ `keyword(EGA/VGA Globals,/// EGA/VGA Globals); `keyword(Data Entry Globals,/// Data Entry Globals); │ └──────────────────────────────────────────────────────────────────────────┘ These are the structures and global variables that are used in the UltraWin library. The structures defined are used for windowing, mouse and printer support. The globals are used for screen and video, Desqview/Windows compatibility, graphics, timer and sound control, background processing, dynamically queued RAM-based or disk-based printing, and the window manager. Include the UW.H file for access to the structures, and the UW_GLOBX.H file for access to the globals. `co(10,1);/// RECT`co(); `co(11,1); typedef struct rect_struct { int x_min, x_max, y_min, y_max; } RECT;`co(); This structure is used for general screen and window area definition, and is used internally by the WINDOW structure. We supply several useful rectangle functions you may wish to utilize in your own code. Refer to the `keyword(Rectangle Functions,[uw_help4.hlp]/// Rectangle Functions); section for more information. `co(10,1);/// WINDOW`co(); `co(11,1); typedef struct w_struct { struct w_struct *next; /* next window in linked list */ struct w_struct *previous; /* previous window in list */ RECT pane; /* the window rectangle */ RECT old_pane; /* for full size toggle */ int rows; /* save buffer rows and columns */ int cols; int csr_x; /* the "soft" cursor location */ int csr_y; uchar att; /* the window's attribute */ uchar bdr_att; /* the window's border attribute */ int bdr_style; /* the border style */ int name_loc; /* CENTERED, LEFTJUST, RIGHTJUST */ char *name; /* pointer to window name */ uchar *save; /* pointer to save buffer area */ uchar *buff; /* pointer to write buffer area */ uchar *mask; /* pointer to window buffer mask */ uchar *tabs; /* tab stops */ int reg_s, reg_e; /* scroll region start and end */ unsigned hidden : 1; /* 1 if window hidden */ unsigned overlapped : 1; /* 1 if window overlapped */ unsigned csr_adv : 1; /* 1 if cursor auto advanced */ unsigned inside : 1; /* 1 if bordered and inside */ unsigned mask_on : 1; /* 1 if window mask is active */ unsigned popup : 1; /* 1 if window is popup */ unsigned scroll : 1; /* 1 if window auto-scrolls */ unsigned bs_clear : 1; /* 1 if backspace is destructive */ unsigned eol_wrap : 1; /* 1 if cursor wraps at end of ln*/ unsigned mgr_flag : 1; /* 1 if win in manager's list */ unsigned set_flag : 1; /* 1 if window is set on screen */ unsigned cr_flag : 1; /* 1 if cr processed */ unsigned lf_flag : 1; /* 1 if lf processed */ unsigned cr_lf_flag : 1; /* 1 if cr or lf act as cr/lf */ unsigned bk_flag : 1; /* 1 if backspace processed */ unsigned tab_flag : 1; /* 1 if tab processed */ unsigned bell_flag : 1; /* 1 if bell char processed */ unsigned w_wrap : 1; /* 1 if word wrap on */ unsigned unused : 14; void *usr_ptr; /* user expansion pointer */ uchar usr_exp[4]; /* user expansion space */ /* DO NOT USE BELOW VARIABLES */ void *sys_ptr; /* system expansion pointer */ uchar sys_exp[4]; /* system expansion space */ } WINDOW;`co(); This structure is used by the UltraWin library for all window operations. The structure is used internally by the library, so the information above is mainly shown to satisfy any curiosity. Starting with version 2.00 of UltraWin, the tabs for the window are allocated on window creation. The tabs are now as large as the width of the window, saving space over the 132 bytes used by previous versions. You will notice that starting with 2.00 both user-defined and system pointers and expansion areas have been added. Please do not access the system additions as we will be using these in future versions. It is recommended that these structure elements be accessed by the functions provided, where available, and not directly. This allows us to change and enhance the package in the future while maintaining compatibility with your code. `co(10,1);/// EVENT`co(); `co(11,1); typedef struct event_struct { int is_mouse; int key; int mod; int m_x, m_y; int m_count, m_button; } EVENT;`co(); This structure is used by the global variable "Event", which is used by wait_event and event_pending to return information. The "is_mouse" member is used as a boolean to indicate if the event was a keyboard event (is_mouse=0) or a mouse event (is_mouse=1). The "key" member will contain the key value, and the member "mod" will contain bit settings to indicate if a key combination was used. This includes the left and right shift combinations, Ctrl or Alt combinations, and whether Scroll Lock, Num Lock, or Caps Lock are set (see UW_KEYS.H for defines). The "m_x" and "m_y" members will contain the x,y coordinate (from 0..V_cols-1 for x, 0..V_rows-1 for y) of the mouse event, "m_count" will contain the number of presses, and "m_button" has the define for the button pressed (LB, MB, or RB). `co(10,1);/// M_RESET`co(); `co(11,1); typedef struct reset_struct { int exists; int n_buttons; } M_RESET;`co(); This structure is used internally by the init_mouse and end_mouse functions. It is used when starting or ending the program, and when first called returns whether or not the mouse is available. The function init_mouse uses this structure to set the global Mouse_exists boolean variable. `co(10,1);/// M_LOC`co(); `co(11,1); typedef struct loc_struct { int button_status; int count; int col; int row; } M_LOC;`co(); This structure is used by m_pos, m_pressed, and m_released, as well as internally by event_pending. If you want to handle the mouse yourself, bypassing UltraWin's event handling capability, use the m_pos, m_pressed and m_released functions to get mouse pressed and coordinate information using a variable of type M_LOC. `co(10,1);/// M_MOVE`co(); `co(11,1); typedef struct move_struct { int h_count; int v_count; } M_MOVE;`co(); This structure is used only by the m_motion function, which reports the net movement of the mouse cursor between m_motion calls. `co(10,1);/// MENU`co(); `co(11,1); typedef struct menu_struct { WINDOW *wnp; /* the window for output */ int direction; /* menu direction, vt or hz */ int num_entries; /* number of entries in menu */ uchar csr_att; /* the cursor attribute */ uchar first_att; /* the first letter attribute */ int csr_pos; /* current cursor position */ uchar first_pos[M_MAX_ENTRIES]; /* first letter position */ int id[M_MAX_ENTRIES]; /* id value for each entry */ uchar x[M_MAX_ENTRIES]; /* x location for each entry */ char *entry[M_MAX_ENTRIES]; /* array of char pointers */ } MENU;`co(); This structure is used internally by the UltraWin menuing functions. The function `keyword(menu_create,[uw_help4.hlp]/// menu_create); sets up the window, direction, and attribute members, while `keyword(item_add,[uw_help4.hlp]/// item_add); sets the entry string, id, first position for the hot key, the x position (used when the menu is horizontal) and increments num_entries. Once the menu has been constructed with menu_create and item_add, you may modify the structure directly to change colors, first positions for hot keys, or an id or menu string on the fly. For example, to change the third entry of the menu pointed to by mnp to the words "Load File" with the 'F' character as the hot key with an id of 32, use: mnp->first_pos[2] = 5; /* first letter in "File" */ mnp->id[2] = 32; /* the new id */ mnp->entry[2] = "Load File"; /* the new string */ `co(10,1);/// PRINT`co(); `co(11,1); typedef struct printer { int active; /* set to 1 if printer init'd/active */ int halt; /* set to 1 to temporarily stop printer */ int prt_dev; /* file handle for printer device */ char device[81]; /* name of printer device */ int prt_buff[2]; /* file handles for printer buffer */ char buffer[81]; /* name of printer buffer */ int cr_cnt; /* number of carriage returns to send */ int lf_cnt; /* number of line feeds to send */ int block_mode; /* allows faster output on block devices*/ long max_que_size; /* maximum size of print que */ long init_que_size; /* initial size of print que */ long curr_que_size; /* current size of print que */ long read; /* print que read index */ long write; /* print que write index */ long cnt; /* print que cnt (number of bytes in q) */ uchar *que; /* pointer to print que data */ uchar *xlat; /* pointer to translation table */ int xlat_flag; /* translation flag */ } PRINT;`co(); This structure is used by the print routines in UW_PRINT.C. For further information, see `keyword(Print Support,[uw_help6.hlp]/// Print Support);. `co(10,1);/// Video Globals`co(); `co(11,1); uchar far *Screen;`co(); This is a far pointer to the video display area. Its value will depend on if you are using a monochrome or color display, and whether a control program like Windows or Desqview is being used. You may modify this variable to redirect output anywhere in memory, but be careful to use an area you are sure is safe. `co(11,1); int V_mode;`co(); This is an integer that contains the text mode that was used before the call to init_video or force_video. This is saved in V_mode and is used in the call to end_video to restore the original mode. `co(11,1); int V_cols, V_rows;`co(); These two variables contain the number of columns and rows available on the text screen, and are set by the init_video and force_video functions. The video screen is therefore defined as 0..V_cols-1 and 0..V_rows-1. `co(10,1);/// Event Globals`co(); `co(11,1); EVENT Event;`co(); This global variable is used by the event_pending and wait_event functions to pass back information about the type of event as well as mouse/keyboard information. `co(11,1); int Mouse_exists;`co(); This global variable is set by the init_mouse function to either TRUE (1) or FALSE (0) depending on whether a Microsoft or compatible mouse is connected. `co(10,1);/// Default Attributes`co(); `co(11,1); uchar Dflt_att, Dflt_bdr_att;`co(); These attributes are used to set the default window colors when wn_create is called. If you do not use the wn_color and wn_bdr_color macros to set the window colors, you will get these default attributes. `co(10,1);/// Cursor Globals`co(); `co(11,1); int Csr_visible;`co(); This boolean is either TRUE (1) or FALSE (0) depending on whether the hardware cursor is visible. `co(11,1); int Csr_in_use;`co(); This boolean is either TRUE (1) or FALSE (0) depending on whether the hardware cursor is being used. The window input routines wn_gets and wn_gets_ll set this variable to TRUE while the cursor is being used, then set it back to FALSE when finished. `co(10,1);/// DesqView Globals`co(); `co(11,1); int DV_seg, DV_off, DV_flag, DV_upd;`co(); These are integers that are used to maintain DesqView compatibility. They are used internal to the library. `co(10,1);/// Manager Globals`co(); `co(11,1); WINDOW *First_window, *Last_window`co(); These are pointers to the first and last windows in the window manager's linked list. These are NULL on startup, and are set by the link_window and unlink_window functions as windows are added to the manager. You can use these to determine the top window (Last_window) or the bottom window (First_window) at any time when using the manager. `co(11,1); int Num_windows`co(); This is a count of the number of windows in the window manager. It is 0 on startup, and increments for every link_window call. `co(10,1);/// Function Globals`co(); `co(11,1); int (*Idle_func)(void) `co(); This is the function that UltraWin calls when it is idle, waiting for an event. You may set your own idle function by calling set_idle_func with the name of your function. To take advantage of the background printing capability of UltraWin you could call `keyword(set_idle_func,[UW_HELP3.HLP]/// set_idle_func); with the function name print_in_background. `co(11,1); int (*Key_func)(int, int) `co(); This is a function pointer hook into the UltraWin key handler. It gets set by the set_key_func function, and points to a user-defined key routine. See `keyword(set_key_func,[UW_HELP3.HLP]/// set_key_func); for further details. `co(11,1); int (*Vld_func)(char*, char*, char*, int, int, WINDOW*) `co(); This is a function pointer to the wn_gets_ll string entry validation routine. It is useful when you want to perform extra error checking on a particular field (as in a valid date). Refer to `keyword(Data Entry,[uw_help4.hlp]/// Data Entry); for more information. `co(11,1); int (*Gets_hook_func)(char*, char*, char*, int, int, int, EVENT*, WINDOW*) `co(); This is a function pointer to the new wn_gets_ll hook. It is set with the set_gets_hook function, and is called from within wn_gets_ll. With this function you can customize wn_gets_ll "on the fly." The function is called on entry, before exiting and on every keystroke. You can modify the passed string, mask and template dynamically, as well as return your own key values. This gives you the ability to customize string entry in virtually any way imaginable! Again refer to `keyword(Data Entry,[uw_help4.hlp]/// Data Entry); for more information. `co(10,1);/// Printer Globals`co(); `co(11,1); PRINT *Printers[MAX_PRINTERS]`co(); This is an array of MAX_PRINTERS (4) pointers to PRINT structures for use in UltraWin's powerful print queue routines. Refer to `keyword(Print Support,[uw_help6.hlp]/// Print Support); for more information. `co(10,1);/// Timer Globals`co(); `co(11,1); int Uw_timers[4]`co(); These are four user timers, which count down toward zero every timer tick from the value you set. For example, if you call init_clock with a value of 0x3333, then to set a one second count-down timer, just use Uw_timer[1] = 91; and after 91 ticks (one second) this second member of the array will reach zero. This occurs even when you are executing your own code as it is modified during the timer interrupt. `co(11,1); int Sys_timers[2], int Sound_timer`co(); These are timers used internally for system timers and the tone function. Access the Uw_timers rather than these for your own use. `co(11,1); int Sound_on`co(); This is a boolean variable that is 1 if the PC speaker is currently sounding a tone, or 0 if it is off. This variable is used internally by tone. `co(11,1); ulong Tics`co(); This is an unsigned long which counts the number of timer ticks since the call to init_clock. With init_clock(0x3333), Tics will increment 91 times every second. You may access this variable in your own program for timing, or reset it to 0 if you want a "count up" timer. `co(11,1); int Tics_per_sec`co(); This is an integer set in init_clock that specifies the number of ticks per second. For init_clock(0x3333), this number will be 91. `co(10,1);/// Graphics Globals`co(); `co(11,1); void (*Graphic_func)(int, int, uchar) `co(); This is a function pointer to a user-defined graphic character output function. Unless init_uw_graphics is called, this pointer is NULL. The graphic character output function outputs a single character at a designated coordinate. When this pointer is not NULL, all UltraWin output goes through this function. Please refer to `keyword(Graphics Support,[uw_help5.hlp]/// Graphics Support); for a complete discussion of using UltraWin in graphic modes. UW_TUT9.C contains an example of this function for use in EGA 640x350x16 or VGA 640x480x16 graphic modes. `co(11,1); int G_opt`co(); This is a boolean flag which specifies whether output optimization should be performed in the graphic output function. The UW_TUT9.C tutorial shows how to implement a graphic output function that checks the contents of each cell to see if output is necessary before actually performing the output. This can result in a very substantial increase in speed. Again refer to `keyword(Graphics Support,[uw_help5.hlp]/// Graphics Support); for more information. `co(10,1);/// EGA/VGA Globals`co(); `co(11,1); int Ega`co(); This is a boolean which is set to 1 when an EGA board is detected by init_video. A VGA board will cause a value of 0. `co(11,1); int Vga`co(); This is a boolean which is set to 1 when a VGA board is detected by init_video. An EGA only board will cause a value of 0. `co(11,1); int EgaVga`co(); This is a boolean which is set to 1 when a board capable of either EGA or VGA is detected by init_video. For more information about EGA/VGA support, see `keyword(Font/EGA Control,[uw_help5.hlp]/// Font/EGA Control); `co(10,1);/// Data Entry Globals`co(); `co(11,1); int Hide_entry_mask;`co(); This variable specifies the "hide" character for the new G_HIDE_ENTRY mode of wn_gets_ll. It is initially set to '*' for use on entry items to hide what is actually typed by the user. This is usefull for entry of content-sensitive fields like program passwords. To change the hide character, just directly set this global. `co(4,7);────────────────────────── /// Video Initialization ──────────────────────────`co(); ┌──────────────────────────────────────────────────────────────────────────┐ │ `keyword(init_video,/// init_video); `keyword(force_video,/// force_video); │ │ `keyword(end_video,/// end_video); `keyword(set_vid_addr,/// set_vid_addr); │ └──────────────────────────────────────────────────────────────────────────┘ These functions allow you to initialize the text screen to a specific mode, and return back to the mode in use before the initialization. Initialization of the text screen is the first step that should be taken in a C program that utilizes the UltraWin library. The UltraWin library supports 80x25 Monochrome and Color modes, as well as the 80x43 EGA color and 80x50 VGA color mode. Higher resolution text screens that some of the new VGA cards can produce are also supported. `co(10,1);/// init_video`co(); `keyword(source,[UW_VID.C]~init_video); Initializes the text screen to a specific mode, specified not by mode number, but by number of columns and rows. The video mode that best matches the number of columns and rows passed will be selected. The function will set the two global variables V_cols and V_rows to the actual number that are available. This allows the user to specify an 80x50 screen, and have init_video set the closest text mode to this size that your video card will accomodate. Prototype: void init_video(int cols, int rows); Parameters: `co(11,1); int cols, int rows`co(); The number of columns and rows desired for the screen. Usage: init_video( 80, 50 ); `co(10,1);/// force_video`co(); `keyword(source,[UW_VID.C]~force_video); This function is similar to init_video, except the text bios mode number is passed as well as the number of columns and rows. This allows one of the non-standard VGA modes (specific to your VGA card) to be set. Prototype: void force_video( int force_mode, int cols, int rows ); Parameters: `co(11,1); int force_mode`co(); The actual mode number listed in the manual for your video board. `co(11,1); int cols, int rows`co(); The number of columns and rows desired for the screen. Usage: force_video( 0x60, 132, 60 ); `co(10,1);/// end_video`co(); `keyword(source,[UW_VID.C]~end_video); Restores the video mode in use before the call to init_video. Call this function just before you exit your program. Prototype: void end_video(void); Parameters: None. Usage: end_video(); `co(10,1);/// set_vid_addr`co(); `keyword(source,[UW_VID.C]~set_vid_addr); This routine overrides the default video address and sets it to the desired segment and offset. Prototype: void set_vid_addr( int segment, int offset ); Parameters: `co(11,1); int segment, offset`co(); The desired segment and offset for your new video address. Usage: `co(11,1); uchar far *old_screen;`co(); ... old_screen = Screen; set_vid_addr( 0xB000, 0x8000 ); ... Screen = old_screen; `co(4,7);───────────────────────────── /// Window Basics ──────────────────────────────`co(); ┌──────────────────────────────────────────────────────────────────────────┐ │ `keyword(wn_create,/// wn_create); `keyword(wn_set,/// wn_set); │ │ `keyword(wn_clear,/// wn_clear); `keyword(wn_border,/// wn_border); │ │ `keyword(wn_move,/// wn_move); `keyword(wn_size,/// wn_size); │ │ `keyword(wn_destroy,/// wn_destroy); │ │ `keyword(set_mask,/// set_mask); `keyword(clear_mask,/// clear_mask); │ └──────────────────────────────────────────────────────────────────────────┘ These are the functions used for basic window creation, destruction, and placement on the text screen. There are special functions that allow you to "mask off" sections of a window so that output does not occur to that area, as well as restoring what was behind a window when it was created. `co(10,1);/// wn_create`co(); `keyword(source,[UW_WN.C]~wn_create); Creates a window with the size determined by the upper left and lower right coordinates passed by integer. Several border styles can be used, as well as a mode for saving what is behind the window, to be restored on window destruction. Please note that wn_create does not allocate the window structure for you. You must declare your window structures as either locals or globals, passing the address of the window to wn_create, or as pointers returned from malloc or calloc. A 1 is returned on success, and a 0 on failure. Prototype: int wn_create( int x_min, int y_min, int x_max, int y_max, int bdr, int mode, WINDOW *wnp ); Parameters: `co(11,1); int x_min, int y_min, int x_max, int y_max`co(); The coordinates of the upper left and lower right corners of the window to create. These range from 0,0 (upper left corner of the screen) to the max number of columns and rows minus one (lower right corner of the screen). `co(11,1); int bdr`co(); The border style to use, namely one of the defines NO_BDR, SGL_BDR, DBL_BDR, SLD_BDR, or DUAL_BDR. `co(11,1); int mode`co(); The popup mode, can be either WN_NORMAL or WN_POPUP. Normal windows when destroyed do not restore what is behind them, while popup windows do. Normal windows therefore use less memory. `co(11,1); WINDOW *wnp`co(); A pointer to the window. Can be the address of a global variable of type WINDOW, or a pointer that has been allocated with malloc or calloc. The wn_create function will initialize the contents of the window for you, so all that is necessary is to pass it to this function. Usage: WINDOW *wnp; ... wn_create( 0, 0, 79, 24, SGL_BDR, POPUP, wnp ); `co(10,1);/// wn_set`co(); `keyword(source,[UW_WN.C]~wn_set); Sets the window on the screen, saving the contents of what is behind the window if it was defined as WN_POPUP when created with wn_create. Prototype: void wn_set( WINDOW *wnp ); Parameters: `co(11,1); WINDOW *wnp`co(); A pointer to the window, or address of a WINDOW variable. Usage: WINDOW *wnp; ... wn_set( wnp ); `co(10,1);/// wn_clear`co(); `keyword(source,[UW_WN.C]~wn_clear); Clears the contents of a window, excluding the border, if present. The window must be first created with wn_create, then set on the video screen with wn_set. Prototype: void wn_clear( WINDOW *wnp ); Parameters: `co(11,1); WINDOW *wnp`co(); A pointer to the window. Usage: WINDOW *wnp; ... wn_clear( wnp ); `co(10,1);/// wn_border`co(); `keyword(source,[UW_BDR.C]~wn_border); Draws the border to the window, if the window border exists (call wn_create with something besides NO_BDR, or set the bdr_style field of the window to one of the border defines). Use this function to redraw the border. Prototype: void wn_border( WINDOW *wnp ); Parameters: `co(11,1); WINDOW *wnp`co(); A pointer to the window. Usage: WINDOW *wnp; ... wn_border( wnp ); `co(10,1);/// wn_move`co(); `keyword(source,[UW_WN.C]~wn_move); Takes a window that has been placed on the video screen with wn_set, and moves it to a new location. Please note that the background will be restored for you when the window is moved if you create the window with the WN_POPUP value as the mode parameter to wn_create. Prototype: void wn_move( int col, int row, WINDOW *wnp ); Parameters: `co(11,1); int col, row`co(); The column and row where the window is to be moved. This location is where the upper left hand corner of the window will be placed. `co(11,1); WINDOW *wnp`co(); A pointer to the window to move. Usage: WINDOW *wnp; ... wn_move( 3, 7, wnp ); `co(10,1);/// wn_size`co(); `keyword(source,[UW_WN.C]~wn_size); Takes a window that has been placed on the video screen with wn_set, and resizes it, either smaller or larger. The window can also be moved in the same operation. Please note that the background will be restored for you when the window is sized if you create the window with the WN_POPUP value as the mode parameter to wn_create. IMPORTANT: The contents of the window are destroyed in this operation. Since the window changes size, it is typically necessary to redisplay the contents to take advantage of the new size. Prototype: int wn_size( int x_min, int y_min, int x_max, int y_max, WINDOW *wnp ); Parameters: `co(11,1); int x_min, int y_min, int x_max, int y_max`co(); The coordinates of the upper left and lower right corners of the window to create. These range from 0,0 (upper left corner of the screen) to the max number of columns and rows minus one (lower right corner of the screen). `co(11,1); WINDOW *wnp`co(); A pointer to the window to move. Usage: WINDOW *wnp; ... wn_size( 3, 7, 74, 18, wnp ); `co(10,1);/// set_mask`co(); `keyword(source,[UW_MASK.C]~set_mask); Checks to see if the second window (top) overlaps the first window (bottom), and masks off (for output) the area that overlaps. Call this function when a window is added on top of another window. If the windows are not overlapped, then no masking is necessary, and the mask is not performed. Masking the bottom window prevents output to the region of the bottom window overlapped, giving the appearance that the window updates "in the background". Call set_mask on a window for each window that is to be displayed "on top" of it. You do not need to use this function when using the window manager, as it takes care of all masking when a window is added or removed! Prototype: void set_mask( int mode, WINDOW *wnp1, WINDOW *wnp2 ); Parameters: `co(11,1); int mode`co(); A value 1 (ON) or 0 (OFF) to indicate if the mask is to be added or removed. `co(11,1); WINDOW *wnp1`co(); The window for which the mask is to be set (the bottom window). `co(11,1); WINDOW *wnp2`co(); The window used to set the mask of the bottom window. (the top window). Usage: WINDOW bottom_win, top_win; ... set_mask(ON, &bottom_win, &top_win); set_mask(OFF, &bottom_win, &top_win); `co(10,1);/// clear_mask`co(); `keyword(source,[UW_MASK.C]~clear_mask); Clears the mask for the window passed. All areas of the window will change when the window is refreshed, or when any information is written to the window, the window scrolls, etc. The window manager will clear any masks necessary when you add or delete windows. Prototype: void clear_mask( WINDOW *wnp ); Parameters: `co(11,1); WINDOW *wnp1`co(); A pointer to type WINDOW that specifies the window to clear. Usage: WINDOW win; ... clear_mask( &win ); `co(10,1);/// wn_destroy`co(); `keyword(source,[UW_WN.C]~wn_destroy); Restores what was behind the window before wn_create (if it was defined using WN_POPUP), and deallocates memory used by the window. Be sure you destroy any temporary window that you have created with wn_create, or you will consume valuable memory. This is also good practice at the end of your program, before calling end_video and returning to DOS. Prototype: void wn_destroy( WINDOW *wnp ); Parameters: `co(11,1); WINDOW *wnp`co(); A pointer to the window, or address of a WINDOW variable. Usage: WINDOW *wnp; ... wn_destroy( wnp );