Quickies for Hacks

---

General

• Disabling the "autorepeat pops up accent menu" [permalink]
  Remember the good old days when holding down 'e' would give you a line of eeeeeeeeeeeeeeeeee? With 10.7, it now pops up an accent panel. If you already know how to make the accents and want your autorepeat back, run this defaults write and relaunch your apps.

  % defaults write -g ApplePressAndHoldEnabled -bool false

• Making naked memory autoreleased [permalink]
  From the devious mind of Rainer Brockerhoff : given a pointer + length, dynamically allocate a copy and make it autoreleased, without (directly) involving cocoa objects. One handy usage: giving a plugin a copy of some struct, but be protected against the plugin messing it up.

  static void *tempCopyOf(void *data,UInt32 size) {
      void *buffer = NULL;
      if (data) {
          buffer = malloc(size);
          if (buffer) {
              bcopy(data,buffer,size);
              [NSData dataWithBytesNoCopy: buffer  length: size  freeWhenDone: YES];
          }
      }
      return (buffer);
  }

  You can get really fancy and assign buffer to calloc(1, size) if you want to give it "pass NULL to get a zero-filled buffer back" semantics.

  Also note this doesn't play well with garbage collection - caveat nerdor. (Thanks to Ken Ferry for that note)

• Posing as a class [permalink]
  Say you wanted to take a peek at how NSSpellChecker does its thing. You can make a subclass, override methods, log interesting stuff, and then send super. Use poseAsClass: to hook yourself into the matrix during the +load method:

  @interface BorkSpellChecker : NSSpellChecker
  {
  }
  @end // BorkSpellChecker
  
  
  @implementation BorkSpellChecker
  
  + (void) load
  {
      NSLog (@"posing");
      [self poseAsClass: [NSSpellChecker class]];
  
  } // load
  
  
  - (void) ignoreWord: (NSString *) word  inSpellDocumentWithTag: (int) tag
  {
      NSLog (@"ignore word: %@  intag: %d",
             word, tag);
      [super ignoreWord: word
             inSpellDocumentWithTag: tag];
  
  } // ignoreWord

• Turning off screen dimming / locking [permalink]
  iDevices after a period of no user interaction will dim the screen and eventually lock it. If you have a hands-free app, or one that's primarily passive, this is unuseful behavior.

  The UIApplication itemTimerDisabled controls whether the screen should dim. Disable it by enabling it:

  [[UIApplication sharedApplication] setIdleTimerDisabled: YES];

  or equivalently

  [UIApplication sharedApplication].idleTimerDisabled = YES;

  Unfortunately, this is not a reliable operation. Sometimes twiddling a UI control or playing music will let the screen dim and lock up. What I ended up doing is toggling the value in a timer:

  [[UIApplication sharedApplication] setIdleTimerDisabled: NO];
  [[UIApplication sharedApplication] setIdleTimerDisabled: YES];

Hacks

• Making the VPN survive fast user switching. [permalink]
  Testing admin vs non admin user scenarios while connected to the mothership VPN is a pain. Heres a way to modify the system configuration plist to make the VPN connection survive fast user switching.

  Open up Internet Connect, select your VPN icon in the toolbar, and choose options from the Connect menu. Uncheck "Disconnect when switching user accounts".

Random

• Exposing documents directory to Files / Finder [permalink]
  Set these both to YES in the Info.plist

  UIFileSharingEnabled
  LSSupportsOpeningDocumentsInPlace
  

• Stopping a chirping G5 [permalink]
  Some (many? all?) G5s make a quiet chirping sound at one-second intervals, like a quiet cricket. It might also chirp when dragging windows or doing something with expose. If that bothers you (like it bothered me), go download CHUD (which you should have already), go to the Processor system preference panel, and turn off "allow nap". That may shorten the life of your machine. But what that means, I have no idea.

---