Hello
You might try something like the following code.
Briefly tested under OS X 10.6.8. Not sure it works well under recent OSes, for it uses old APIs.
Hope this may help,
H
/*
file:
main.c
function:
get and set capslock state
complie:
gcc -std=c99 -framework IOKit -framework CoreFoundation -o capslock main.c
usage:
./capslock [0|1|-1]
0 : capslock off
1 : capslock on
-1 : toggle capslock state
: print current capslock state (0|1)
* written and published as free software by Hiroto, 2015-06
*/
#include <IOKit/IOKitLib.h>
#include <IOKit/hidsystem/IOHIDLib.h>
#include <IOKit/hidsystem/IOHIDParameter.h>
#include <CoreFoundation/CoreFoundation.h>
#include <libgen.h> // basename
#define CAPSLOCK_OFF 0
#define CAPSLOCK_ON 1
#define CAPSLOCK_TOGGLE -1
#define CAPSLOCK_QUERY 9
int main(int argc, char ** argv)
{
kern_return_t kr;
io_service_t ios;
io_connect_t ioc;
CFMutableDictionaryRef mdict;
int op;
bool state;
if (argc < 2)
op = CAPSLOCK_QUERY;
else
op = atoi(argv[1]);
if (op != CAPSLOCK_ON && op != CAPSLOCK_OFF && op != CAPSLOCK_TOGGLE && op != CAPSLOCK_QUERY)
{
fprintf(stderr, "Usage: %s %s\n\t\%s\n\t%s\n\t%s\n\t%s\n",
basename(argv[0]),
"[0|1|-1]",
" 0 : capslock off",
" 1 : capslock on",
"-1 : toggle capslock state",
" : print current capslock state (0|1)"
);
return 1;
}
mdict = IOServiceMatching(kIOHIDSystemClass);
ios = IOServiceGetMatchingService(kIOMasterPortDefault, (CFDictionaryRef) mdict);
if (!ios)
{
if (mdict)
CFRelease(mdict);
fprintf(stderr, "IOServiceGetMatchingService() failed: %x\n", kr);
return (int) kr;
}
kr = IOServiceOpen(ios, mach_task_self(), kIOHIDParamConnectType, &ioc);
IOObjectRelease(ios);
if (kr != KERN_SUCCESS)
{
fprintf(stderr, "IOServiceOpen() failed: %x\n", kr);
return (int) kr;
}
switch (op)
{
case CAPSLOCK_ON:
case CAPSLOCK_OFF:
state = (op == CAPSLOCK_ON);
kr = IOHIDSetModifierLockState(ioc, kIOHIDCapsLockState, state);
if (kr != KERN_SUCCESS)
{
IOServiceClose(ioc);
fprintf(stderr, "IOHIDSetModifierLockState() failed: %x\n", kr);
return (int) kr;
}
break;
case CAPSLOCK_TOGGLE:
kr = IOHIDGetModifierLockState(ioc, kIOHIDCapsLockState, &state);
if (kr != KERN_SUCCESS)
{
IOServiceClose(ioc);
fprintf(stderr, "IOHIDGetModifierLockState() failed: %x\n", kr);
return (int) kr;
}
state = !state;
kr = IOHIDSetModifierLockState(ioc, kIOHIDCapsLockState, state);
if (kr != KERN_SUCCESS)
{
IOServiceClose(ioc);
fprintf(stderr, "IOHIDSetModifierLockState() failed: %x\n", kr);
return (int) kr;
}
break;
case CAPSLOCK_QUERY:
kr = IOHIDGetModifierLockState(ioc, kIOHIDCapsLockState, &state);
if (kr != KERN_SUCCESS)
{
IOServiceClose(ioc);
fprintf(stderr, "IOHIDGetModifierLockState() failed: %x\n", kr);
return (int) kr;
}
break;
}
IOServiceClose(ioc);
fprintf(stdout, "%d", (int) state);
return 0;
}
