Mac command line gold!

Mac command line gold!

Copy a file to the clipboard:

$ cat ~/.zshrc | pbcopy

The contents of my .zshrc are now on the clipboard and I can paste them into any other application (, Word, whatever).

Paste the clipboard contents to the shell:

$ pbpaste > foo.txt

Anything that was on the clipboard is now in the file foo.txt.

Fixing Java tools on Snow Leopard

I was attempting to work with VisualVM and Tomcat over the past few days on Snow Leopard and it was constantly failing. I was getting errors like this:

    "attach: task_for_pid(59980) failed (5)"

I was also getting errors inside VisualVM and from the command like using jmap that went like this:

Attaching to process ID 61218, please wait...
sun.jvm.hotspot.debugger.NoSuchSymbolException: Could not find symbol "heapOopSize" in any of the known library names (-)
	at sun.jvm.hotspot.HotSpotTypeDataBase.lookupInProcess(
	at sun.jvm.hotspot.HotSpotTypeDataBase.readVMIntConstants(
	at sun.jvm.hotspot.HotSpotTypeDataBase.<init>(
	at sun.jvm.hotspot.MacOSXTypeDataBase.<init>(
	at sun.jvm.hotspot.bugspot.BugSpotAgent.setupVM(
	at sun.jvm.hotspot.bugspot.BugSpotAgent.go(
	at sun.jvm.hotspot.bugspot.BugSpotAgent.attach(
	at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
	at sun.reflect.NativeMethodAccessorImpl.invoke(
	at sun.reflect.DelegatingMethodAccessorImpl.invoke(
	at java.lang.reflect.Method.invoke(
Debugger attached successfully. requires a java VM process/core!

And I also got some other strange errors from jmap like this one:

61218: Unable to open socket file: target process not responding or HotSpot VM not loaded
The -F option can be used when the target process is not responding

I opened an issue with the VisualVM team and they tested things out on Snow Leopard and said it all worked fine. I figured they were smokin’ something and decided to try a Sun product and see if it worked. I fired up NetBeans and sure enough, VisualVM and jmap worked great. This indicated it was definitely a VM configuration issue.

Here’s the what you need to do to get your Java applications working with the VM tools on Snow Leopard. Add the following parameters to the java command and everything will start working fine:

java -Xverify:none -Xshare:off

The -Xverify:none is the setting that allows VisualVM and jmap to capture thread dumps. Without this setting, you’ll get strange errors like those above. The -Xshare:off gets VisualVM working without any startup errors or random failures. The last setting is really just for JConsole and other JMX tools.


Fixing macbook wake up problems

One of the family Apple notebooks (a Macbook) was having some issues waking up from sleep periodically. It was also having issues when the lid was closed the fan would constantly spin as though the machine was overheating. I took the machine into the only Apple store I trust (the main tech there is pretty solid, although he still doesn’t use Terminal). The fix was pretty simple:

  1. Open up Terminal (Google it if you’ve never done it)
  2. Type in ‘cd /var/vm’
  3. Type in ‘rm sleepimage’

It looks like this:

$ cd /var/vm
$ rm sleepimage

This should fix any issues with sleeping and waking up. The root cause is that if you move the machine to fast, have any static electricity and shock the machine, or otherwise jostle it too much when it is going into sleep mode (just after you close the lid), the sleep image will become corrupt and you’ll start having issues.

Android review and iPhone comparison

Here’s a quick run-down and comparison between the G1 vs. iPhone and Andriod vs. OS X mobile. This is based on side-by-side evaluation with both phones.

The phones


The winner: G1

The G1’s keyboard is awesome. I like it so much better than the iPhones mainly because I can see the whole screen while typing, but also because it has numbers and I don’t have to hit something to switch between numbers and letters. I’m a keyboard freak, so hands down the G1 wins.


The winner: iPhone

I think this is close to a tie, but the iPhone screen is bigger. The resolution is the same for both phones, which means that the G1 can display as much information as the iPhone, but it is smaller.


The winner: iPhone

The iPhone’s battery is 2-3 times better than the G1’s. I’ve heard word of T-Mobile shipping out batteries that add 30% more life, but even still, I play around with my G1 very little and it still needs to be charged daily. My iPhone needs charging every 2-3 days with the same use.

Form factor/Design

The winner: iPhone

This isn’t much of a battle. The iPhone is sleek, light and really nice to look at. The G1 is thicker, heavier and an eye-sore comparatively. However, I can understand the extra size given the full keyboard. One thing the G1 does nicely is it figured out the exact size required for anyone to hold it in one hand and use any feature of the phone. This is the only thing nice about the G1’s size and shape.


The winner: G1

I like the buttons and track ball with the G1. The iPhone is sometimes a bit cumbersome to use given that everything is on the screen. Sometimes it is nice to just hit a button.


The winner: iPhone

The iPhone has a really good accelerometer that seems to be level and responsive. The G1’s is a little rough around the edges and you can’t calibrate it or tweak it at all.

The operating systems and software


The winner: Android

Android has a lot of advanced features that are pretty nice overall. Each application has a menu, which is great for adding loads of functionality. There are keyboard shortcuts in applications which makes using features fast. Android has intents which are nice. It also allows applications to leverage other applications and common libraries. By far, Android wins when it comes to a modern platform.

At the same time though, Android has many bugs and issues that also make it difficult to actually use.

Homepage/Application Chooser

The winner: Tie

The iPhone home page doesn’t have the cool backgrounds or the lame analog clock or the drag and drop application display, but it is simple, orderable (you can move apps around), and looks really nice. Androids has a cool homepage that allows ordering and an alphabetized app chooser. So, they are different, but equally as usable and cool.

Androids icons definitely have that Linux look, which I grew tired of a decade ago while iPhone’s icons are sleek and nice and I haven’t gotten tired of yet (only 1 year as a Mac user). It seems like Apple is more in tune with style and each OS release keeps things fresh. We’ll see how 10.6 goes. Linux on the other hand just plain sucks the life out of you.


The winner: OS X

T-Mobile and Android’s voicemail integration is horrible. It is exactly the same as every other phone for T-Mobile because you have to dial into voicemail and manage it via T-Mobile’s phone system. There is an 3rd party application that adds visual voicemail to Android phones, but it is in beta and it is a hack that appears to actually dial up your voicemail and record the voicemails to an MP3. I’m not positive on that, but this is what it seems like. Regardless of how this application works, it is a 3rd party application and T-Mobile and Android should really be offering a tightly integrated feature of the phone.

The iPhone completely integrates with AT&T’s voicemail such that you can view all your voicemails on the phone, listen to them on the phone, and even setup and switch your voicemail greeting on the phone.


The winner: Android

The Android Google calendar integration is great. However, it doesn’t support multiple calendars very well (you can only view calendars in the associated GMail account and not other GMail accounts or an Exchange calendar) and that’s a real pain point for most. Since I use a single calendar for everything, I don’t mind too much. On the other hand, if you have a Mac and only use, integration with the iPhone is great. This combined with Mobile Me would be ideal for real-time updates and syncing. For now though, Android wins in this department.

I’d imagine that Google will soon offer syncing with the iPhone as it does with the BlackBerry. If not, NuevaSync will work once it is finished and out of Beta.

Likewise, I would put money that Android will start supporting multiple calendars shortly.


The winner: OS X

Multi-touch, double-click and good integration/features wins this battle. Since you are already touching the screen to move around, multi-touch is nice. The G1’s map interface is nice and it does allow single handed use, but iPhone’s bigger screen and multi-touch prevail in this category.


The winner: OS X

First, the GMail application really should be combined with the Email application. The fact that they are separate is really painful and annoying. Email should just be email like the iPhone does. Second, Android’s email application is one of the worst applications ever written. Here are a few of the pain points:

  • Can’t view first few lines of emails in the inbox view
  • The folder and email view are combined making for a very cluttered interface
  • Email fails regularly even when connected to a WiFi
  • Deleting emails does nothing for GMail accounts via IMAP.
  • Can’t setup what happens on delete for IMAP accounts. For example, with GMail IMAP it should move the message to [Gmail]/Trash

The worst thing is probably that the Email application doesn’t instantly work with GMail IMAP accounts. This should just work considering that the entire platform and stock applications are written by Google. I mean come on guys, take a cue from Apple and just make stuff work, especially with your own systems. Plus, Email constantly crashes and has so many issues that it is rendered useless in most situations.

The iPhone email isn’t perfect, but it handles all of these things much better and also makes setting up GMail accounts a snap.

Document Viewer

The winner: OS X

The iPhone has a built in PDF viewer that works really well. It also displays Word documents and other formats decently well. In gets a little bit freaked out by complex Word documents in the new DOCX format, but otherwise it is great. It also allows you to zoom in and out using multi-touch and double-click.

The G1 looks like it uses Google Docs online viewer or some type of hacky internal viewer. Not really sure about which one, but it does a very poor job of displaying documents and files, including PDF (I mean really? PDF? It should perfectly display all PDFs). Images are also displayed poorly and some don’t render correctly, such as JPGs. Plus, no zoom (ouch!).


The winner: OS X

This is based purely on the most fundamental of all applications, solitaire. There are a number of choices on both phones, but overall the solitaire on the iPhone is much nicely in terms of design, features, etc.

App stores

The winner: OS X

Apple’s store has a much cleaner interface and includes pictures, better details, better commenting system and more interactivity. The Android market looks pretty shabby comparatively.


The winner: OS X

The iPhone uses the accelerometer all over the place and it does it really well. Orientation of the phone is really helpful in most applications as it makes the phone easy to use.

Android’s support for orientation and the G1’s accelerometer is just garbage. Even the browser requires 3-4 clicks before you can change the orientation without opening the keyboard. I mean come on guys, just use the tools you have and make people’s lives simple. Plus, HTC seems like they added a pretty low end accelerometer and it isn’t calibrated very well. Plus, you can’t really calibrate it.


The winner: Android

I’ve talked at length about how I think Objective-C is really keeping Apple back, but here’s another way to look at it. If you take the years that technologies were introduced and line them up so that you have language, RAM, and CPU (based on speed), here are the results:

iPhone: 1986 1989 2000
G1: 1995 1996 2000

I definitely like the G1 and Android numbers much better.

The Final Score

If we add all these up, it looks like this:

G1/Android: 5

iPhone/OS X: 11

The final winner? iPhone/OS X

Getting the current system time in milliseconds with C++

After doing quite a bit of C++ recently, I thought I would post my method for getting the current system time in milliseconds in C++ for both Mac OS X and Windows. The Mac version might translate to other Unix platforms, but you’ll have to check the docs or man pages.

Mac OS X

#include <sys/time.h>
timeval time;
gettimeofday(&time, NULL);
long millis = (time.tv_sec * 1000) + (time.tv_usec / 1000);

This actually returns a struct that has microsecond precision.


#include "windows.h"
WORD millis = (time.wSeconds * 1000) + time.wMilliseconds;

This code gives the milliseconds within the last minute. If you want milliseconds since epoch or some other fixed point in time it will require a bit more math on the SYSTEMTIME struct.

git completion in zsh

Just figured out how to get git tab completion working in zsh on a Mac. Turns out that the completion scripts use a bunch of extra git commands such as git-ls-files. These commands need to be in your path for the completion to work. If you installed git using the OS X installer, you need to add this directory to your path:


Android, iPhone, Java, Objective-C… madness

Russ Teabeault and I were just talking about our recent experiences with Objective-C and developing applications for either the iPhone or OS X. In general, we both agree that Objective-C is necessary, but painful. The language is quasi-dynamic, not very modern and poorly adopted.

Let me clarify that a bit. Objective-C is dynamic but lacks nice features that most modern dynamic languages provide such as closures (although these aren’t strictly tied to dynamic languages by any means). It also uses a fairly non-standard message passing syntax, that is probably because it had to select something that would not conflict with C and C++. It also still uses header files and lacks good namespacing, both of which are obvious signs of antiquity. Plus, we both shared stories of having impossible times finding good open source libraries, tools and framework. The last bit of our conversation was the extreme lackluster of the XCode IDE, which is more like a text editor than a modern development environment.

I mentioned that prior to 10.4, Apple had provided integration of most of the Cocoa libraries with Java and had even written some OS applications in Java. Not surprising, we both thought the shift from Java to Objective-C was a step in the wrong direction. It seemed as though the correct direction would be a better, faster and more integrated VM that would run many languages including Java, much like the CLR offers developers on Windows. Instead, Apple seems to be chugging along the CPU native path and providing bridges between Objective-C and various scripting languages. This means that each new language they want to support on the operating systems requires work to bridge effectively and that work can only be done well by Apple. If they had gone down the VM path, new languages would be supported once the community built support for them on the VM. Therefore, if I wanted to write my next application for OS X in Scala, I could.

This brought us to a discussion of the merits of Android for mobile development. This is where we had different opinions. I think Android will be great and the development community and support behind it will be much larger than the iPhone. He thought that Apple might release a Java VM for the iPhone if Android picks up steam and believes that the iPhone is still the best platform for mobile.

The reason I like the idea of Android (although the G1 might be a crappy implementation without the ease of use and cool features of the iPhone) because it was fundamentally VM based. This meant that the platform was based on Java-byte code rather than the CPU instruction set. It also meant that the platform had modern concepts like garbage collection, memory management, ClassLoading and all the other good parts of the VM. But it also meant that it will be capable of running any Java-byte code regardless of the language it is written in. Therefore, I could write my Android application in Groovy and with the help of a few extra JARs, get it running just as well as plain old Java.

(Update 10/22/08 Groovy doesn’t quite work yet, because of a number of additional classes and JARs it uses. However, the principle is sound because Android is VM based. JRuby might be a better solution than Groovy depending.)

The problem with the iPhone is that it is tied directly to the CPU instruction set and the Objective-C language. This means you take a step backwards 20 years and now have all the overhead of header files, pre-compilers, directives, manual memory management, no-namespacing, and numerous other headaches that VMs have done exceedingly well in fixing.

What I wonder is why Microsoft is the only operating system company to figure out that wiring a VM, capable of everything we except out of a modern VM plus application isolation, into the lowest levels of the OS is a great idea. In fact, this idea is fantastic. This means applications targeted to the VM improve as the VM improves, without any code changes.

The Java VM still has a long way to go to catch up with the CLR as a full platform. JSR 121 was finalized a few years back, which will provide good application isolation within a single Java VM instance. This means that you can start up the Java VM and then run multiple applications inside it without any conflicts or concerns about one application impacting the others (such as an application calling System.exit or running out of memory). The Java VM still needs extremely tight integration with the operating system and needs to be started when the OS boots. It also needs new ways to start applications and manage applications, which JSRs 277 and 294 should help with. I think though that Google has done all of this work for Android. It runs multiple applications in isolation well, it provides a mechanism for applications to start and stop and the Java VM is completely integrated into the operating system of the mobile device.

I think this is the way of the future. I’m just trying to figure out where Apple is going and why they are heading that way.

Hidden folders in OS X file dialogs

Found a good shortcut for getting access to hidden folders in OS X file dialogs and the Finder. It requires some typing and it doesn’t auto-complete like Linux does, but it is better than nothing. Just hit Shift-Command-G to open the “Go To Folder” dialog and then type the path to the hidden file or folder. The path can be relative.

Now, just need to figure out how to access hidden files from the Finder and file dialogs.

[Edit 08/09/2008] The issue is that using the AppleShowAllFiles configuration doesn’t work in dialog boxes and if you enable it, opening Finder in your home directory gets REALLY messy. What Apple needs is the same feature that Linux has had for a long time: the ability to show and hide hidden files in dialogs and finder using a keyboard shortcut or menu option. I believe Linux uses ctrl-h for this. Apple could use something like cmd-shift-h or something.