Category : Files from Magazines
Archive   : PJ62.ZIP
Filename : TSR.H

Code from "Converting a Turbo C Program to a TSR" by Michael J.
Young, PJ, Volume 6.2. Copyright 1987 Michael J. Young.

Listing 2

/* Error codes returned by 'TsrInstall' if it cannot install the TSR. */

#define ERROR 1 /* General, undefined error. */
#define WRONGDOS 2 /* Version of DOS prior to 2.0. */
#define INSTALLED 3 /* TSR has already been installed in memory. */
#define NOINT 4 /* No free user interrupts are available. */

/* Constant definitions for hotkey shift mask. */

#define RIGHTSHIFT 0x0001
#define LEFTSHIFT 0x0002
#define CONTROL 0x0004
#define ALT 0x0008
#define SCROLLSTATE 0x0010
#define NUMLOCKSTATE 0x0020
#define CAPLOCKSTATE 0x0040
#define INSERTSTATE 0x0080
#define CTRLNUMLKSTATE 0x0800
#define SCROLLLOCK 0x1000
#define NUMLOCK 0x2000
#define CAPSLOCK 0x4000
#define INSERT 0x8000

/* Variables and functions. */

typedef void interrupt (*VIFP) (); /* Void Interrupt Function Pointer. */
int TsrInstall (void (*FPtr) (void),int HotKey, VIFP Code);
int TsrInDos (void);