Command: c_func
  
Platform :
  WIN32 , Linux
  
Syntax: 
  x = c_func(i, s)
  
Description: 
  Call the C function with routine id i. i must be a valid routine
  id returned by define_c_func. s is a sequence of argument values 
  of length n, where n is the number of arguments required by 
  the function. x will be the result returned by the C function.
  
Comments: 
  If the C function does not take any arguments then s should 
  be {}.
  
Example: 
     
      -- open user32.dll - it contains the BeginPaint C function
      user32 = open_dll("user32.dll")  
      
      -- the C function BeginPaint takes a C int argument and
      -- a C pointer, and returns a C int as a result:
      BeginPaint = define_c_func(user32, "BeginPaint", 
         {C_INT, C_POINTER}, C_INT)

              -- call BeginPaint, passing hwnd and ps as the arguments,
              -- hdc is assigned the result:
              hdc = c_func(BeginPaint, {hwnd, ps})

See Also: 
  c_proc, define_c_func
  
