os x lock screen

lockscreen.m

#import <objc/runtime.h>
#import <Foundation/Foundation.h>

/*
  lockscreen.m

  to compile:

    clang -framework Foundation lockscreen.m -o lockscreen

  then bind a keyboard shortcut (e.g., with Hammerspoon or automator)
  to run this program

  original post:
  http://apple.stackexchange.com/questions/80058/lock-screen-command-one-liner
  original authors:
  - http://apple.stackexchange.com/users/72534/jnk
  - http://apple.stackexchange.com/users/68832/mrb
*/

int main () {
    NSBundle *bundle = [NSBundle bundleWithPath:@"/Applications/Utilities/Keychain Access.app/Contents/Resources/Keychain.menu"];
    Class principalClass = [bundle principalClass];
    id instance = [[principalClass alloc] init];
    [instance performSelector:@selector(_lockScreenMenuHit:) withObject:nil];
    return 0;
}