VIO Tutorial (Hello, World)
From EDM2
This is a short tutorial on writing text to the console, the basics, and then with some color and cursor positioning.
- All examples have been compiled with OpenWatcom.
VIO is short for Video Input/Output, and is the console interface to eCS.
The following is a hello, world application for the eCS VIO API.
#define INCL_VIO #include <os2.h> int main( int argc, char *argv[] ) { APIRET rc = VioWrtTTY( "Hello, VIO\n", // string to write 11, // lenght of string to write 0 ); // VIO handle, must be 0 return rc; }
This can be compiled with OpenWatcom 1.3, as such: WCL386 vio.cpp, assuming the file name of vio.cpp.
Because of the non-standard style comments (double slash format) the option for the IBM C compiler should be: icc /Ss+ vio.c
Character Attributes
- Lower Nibble (Character)
- Bit 0: Blue (0x01)
- Bit 1: Green (0x02)
- Bit 2: Red (0x04)
- Bit 3: Intensity (0x08)
- Higher Nibble (Background)
- Bit 4: Blue (0x10)
- Bit 5: Green (0x20)
- Bit 6: Red (0x40)
- Bit 7: Blink/Intensity (0x80) (VioSetState)
Color Example
#define INCL_VIO #include <os2.h> int main( int argc, char *argv[] ) { char buffer[32] = { 'H', 12, // intense red 'e', 9, // intense blue 'l', 10, // intense green 'l', 12, 'o', 9, ',', 10, ' ', 0, 'i', 12, 'n', 9, ' ', 0, 'c', 10, 'o', 12, 'l', 9, 'o', 10, 'r', 12, '!', 9 }; APIRET rc = VioWrtCellStr( buffer, 32, // Buffer length 3, // Row, 3 to allow some scrolling 0, // Column 0 ); // VioHandle, must be 0 return rc; }