Introduction Video Functions
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 CHARPIX()    Returns the number of pixel lines per character
 CHARWIN()    Exchanges particular characters in a screen area.
 CLEAREOL()   Clears from the cursor position to the end of line
 CLEARSLOW()  Deletes a screen area from the outside in with a delay
 CLEARWIN()   Clears a screen area
 CLEOL()      Clears characters and attributes to the end of a line
 CLWIN()      Clears character and attribute from a screen area
 COLORREPL()  Exchanges particular screen attributes
 COLORTON()   Converts NN/NN or CC/CC color values into numeric values
 COLORWIN()   Exchanges particular attributes in a screen area
 EGAPALETTE() Changes EGA palette colors
 ENHANCED()   Selects the enhanced color value for SET COLOR TO output
 FILESCREEN() Reads screen content from a file
 FONTLOAD()   Loads EGA/VGA fonts from another file
 FONTRESET()  Resets all font and palette changes to the ROM defaults
 FONTROTATE() Rotates and mirrors images within a font string
 FONTSELECT() Determines font areas for normal- and high-intensity output
 GETCLEARA()  Queries the current attribute for the clearing functions
 GETCLEARB()  Queries the default character for the clearing functions
 GETFONT()    Queries the current font
 GETSCRSTR()  Queries screen output that was redirected by SETSCRSTR()
 GETVGAPAL()  Determines the palette settings on a VGA card
 INVERTATTR() Inverts the foreground and background of an attribute
 INVERTWIN()  Inverts all attributes in an area of the screen
 ISCGA()      Tests for presence of a CGA card or if one can be emulated
 ISEGA()      Determines if an EGA card is present or can be emulated
 ISHERCULES() Determines if a HERCULES card is present or can be emulated
 ISMCGA()     Determines if an MCGA card is present or can be emulated
 ISMONO()     Determines if a monochrome card is present or can be emulated
 ISPGA()      Determines if a PGA card is present or can be emulated
 ISVGA()      Determines if a VGA card is present
 MAXFONT()    Determines the number of available fonts
 MONISWITCH() Switches between monochrome and color screen
 NTOCOLOR()   Converts a numeric value into a color value
 NUMCOL()     Restores the number of available screen columns
 RESTCURSOR() Restores a saved cursor position and form
 SAVECURSOR() Saves current cursor position and form
 SAYDOWN()    Displays screen output downward and vertically
 SAYMOVEIN()  Displays screen output with a "move in" effect
 SAYSCREEN()  Output to the screen without changing the attribute
 SAYSPREAD()  Displays screen output with "spread" effect
 SCREENATTR() Determines the attribute at a particular position
 SCREENFILE() Writes screen content to a file
 SCREENMARK() Searches for a string and marks it with an attribute
 SCREENMIX()  Mixes characters and attributes of a screen
 SCREENSIZE() Queries the number of characters that can be displayed
 SCREENSTR()  Reads a string, including attributes, from the screen
 SETCLEARA()  Changes the default attribute for screen clear
 SETCLEARB()  Changes the default character for screen clear
 SETFONT()    Loads the font directly out of a string
 SETRC()      Sets line and column for the CA-Clipper cursor
 SETSCRSTR()  Redirects screen output into a string
 STANDARD()   Selects the standard color value for SET COLOR TO output
 STRSCREEN()  Displays a string with characters and attributes on the screen
 UNSELECTED() Selects the unselected color value for SET COLOR TO output
 UNTEXTWIN()  Replaces an area of characters from a region of the screen
 VGAPALETTE() Changes VGA palette colors
 VIDEOINIT()  Reinitializes a video system after a RUN
 VIDEOSETUP() Queries video mode at system start
 VIDEOTYPE()  Returns bit-coded information about available video modes