VDisplayButtonAction - displays the button messages in the button window.
  VDisplayButtonAction(msg1, msg2, msg3)
  char *msg1, *msg2, *msg3;
  VDisplayButtonAction displays the mouse button action messages in the mouse
window. Each button action message can have up to MAX_BUTT_MSG_LINES (defined
in 3DVIEWNIX.PAR) number of lines. Each message line can have upto 
MAX_BUTT_CHARS number of characters. VDisplayButtonAction displays just the 
first MAX_BUTT_CHARS on the screen if the number of characters in a message 
line exceeds this number, and return an error code 224. The line separator is 
"\n". For example if there are two lines in a message for the left button, one
line for the middle button, and no message for the right button, then the call
to VDisplayButtonAction would be
If any message is more than MAX_BUTT_MSG_LINES lines, the first
MAX_BUTT_MSG_LINES lines are displayed and the error code 212 is returned.
VDisplayButtonAction allows highlighting  a set of characters in each message
by enclosing them within []. For example to highlight "XYZ" in the left
button message, the call to VDisplayButtonAction would be
If only "[" is specified and not "]", then VDisplayButtonAction highlights
from the character next to "[" to the end of the line. If "]" is specified
and not "[", then VDisplayButtonAction does not highlight any character in
the line.
Return Value
  0 - work successfully.
  212 - button message is more than three lines.
  224 - message displayed is out of window boundary.
  msg1, msg2, msg3 - specifies button status message to be displayed in the
        button window.
Side Effects
Entry Conditions
  If msg1, msg2, or msg3 is NULL, or VCreateColormap is not called earlier,
VDisplayButtonAction prints an error message to the standard error stream, 
produces a core dump file and exits from the current process.
Related Functions
VDisplayImageMessage, VDisplayDialogMessage.