How does Mach-O loader loads different NSString objects?

Posted by overboming on Stack Overflow See other posts from Stack Overflow or by overboming
Published on 2010-05-22T15:58:11Z Indexed on 2010/05/22 16:30 UTC
Read the original article Hit count: 292

Filed under:

objective-c

|

mac

|

macosx

|

loader

|

mach-o

I have known that If you define a bunch of @"" NSString objects in the source code in Mac OS. These NSStrings will be stored in a segment in the Mach-O library.

Section
sectname __ustring
 segname __TEXT
    addr 0x000b3b54
    size 0x000001b7
  offset 731988
   align 2^1 (2)
  reloff 0
  nreloc 0
   flags 0x00000000
reserved1 0
reserved2 0

If I hex dump the binary, they are aligned closely one by one with a 0x0000as separator. What I want to know is how does the loader in Mac OS X load these NSStrings when the program runs? Are they loaded simpily by recognize the 0x0000 separator or these is a string offset table elsewhere in the binary pointing to separate NSString objects? Thanks.

(What I really want to do is the increase the length of one of the NSString, so I have to know how the loader recognize these separate objects)

© Stack Overflow or respective owner

Related posts about objective-c

Objective-C with some Objective-C++, calling a normal c++ method "referenced from" problem

as seen on Stack Overflow - Search for 'Stack Overflow'
Hi, I made an Objective-C project for the iPhone. I had only one cpp class, the soundEngine taken from some Apple demo. Now I'm trying to merge OpenFeint which is coded in Objective-C++. As soon as I drop in the code without even referring to it from my code, when I hit Build, my Objective-C code… >>> More
Blocking access to websites with objective-C / root privileges in objective-C

as seen on Stack Overflow - Search for 'Stack Overflow'
I am writing a program in Objective-C (XCode 3.2, on Snow Leopard) that is capable of either selectively blocking certain sites for a duration or only allow certain sites (and thus block all others) for a duration. The reasoning behind this program is rather simple. I tend to get distracted when I… >>> More
Add an objective @property attribute in objective-c

as seen on Stack Overflow - Search for 'Stack Overflow'
Does anyone know of a way to add additional attribute types to the @property keyword without modifying the compiler? Or can anyone think of another way to genericize getter/setter creation? Basically, I have a lot of cases in a recent project where it's handy for objects to lazily instantiate their… >>> More
ObjectiveC Syntax for Specifying Protocol Name in Method Argument

as seen on Stack Overflow - Search for 'Stack Overflow'
What's the ObjectiveC syntax for specifying a protocol as an argument in a method? Say I have 2 protocols, MyProtocol and MyProtocolCB: @protocol MyProtocolCB <NSObject> - (void) func; @end @protocol MyProtocol <NSObject> - (void) register:(MyProtocolCB*) cb; @end I'm receiving this… >>> More
ObjectiveC builtin template system ?

as seen on Stack Overflow - Search for 'Stack Overflow'
I am developing an iPhone application and I use HTML to display formatted text. I often display the same webpage, but with a different content. I would like to use a template HTML file, and then fill it with my diffent values. I wonder if ObjectiveC has a template system similar to ERB in Ruby. That… >>> More

Related posts about mac

Need a non-Mac keyboard alternative for Mac users

as seen on Super User - Search for 'Super User'
I'm a Macbook Pro user. I like Apple products in general, but I hate their keyboards. I work on my computer/laptop 10+ hours a day, so I would like to have a keyboard that is Mac-compatible and ergonomic. I found this one on Amazon. It is specifically made for Mac. However, I would like to get some… >>> More
Including an embedded framework using a cross-project-reference: Header no such file or directory

as seen on Stack Overflow - Search for 'Stack Overflow'
I'm trying to create a Cocoa framework by using a cross-project reference in Xcode. I have 2 projects: one for the framework; one for the application that will use the framework. This framework is not intended to be stored within the system; it is an embedded framework that lives within the application… >>> More
C# development with Mono and MonoDevelop

as seen on Developer IT - Search for 'Developer IT'
In the past two years, I have been developing .NET from my MacBook by running Windows XP into VM Ware and more recently into Virtual Box from OS X. This way, I could install Visual Studio and be able to work seamlessly. But, this way of working has a major down side: it kills the battery of my laptop…… >>> More
12.04lts: no network internet

as seen on Ask Ubuntu - Search for 'Ask Ubuntu'
Friends-- Cannot connect reliably to ethernet nor at all to Internet: Symptoms: About 2 weeks ago did an upgrade. Have not been able to connect to ethernet nor Internet. Today, for example, boot up this System76 laptop and there was no network connection. Did sudo mount -a and got some internal… >>> More
Why i disconnect every few seconds? using USB wireless adapter

as seen on Ask Ubuntu - Search for 'Ask Ubuntu'
i know it's for ubuntu questions..but mint and ubuntu are very similiar and i had the same problem with linux ubuntu too..so i think this is the right place for my question anyway i don't have experience with drivers and other things,after installing Linux on my machine( i did dist-upgrade btw) everything… >>> More