From the dyld Release Notes (Tiger):

** Prebinding is deprecated **

In Mac OS X 10.4, unprebound applications launch about as fast as prebound applications. Therefore, application developers need no longer spend any time trying to built prebound applications. – DevinBayer

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PrebindingFrameworks is an optimization that is worth investigating. Read this document first before doing anything else:

file:///Developer/Documentation/ReleaseNotes/Prebinding.html

PrebindingFrameworks can be tricky because the address ranges of frameworks under development are constantly moving targets (no pun intended). You must have a game plan before assigning base virtual memory addresses to the frameworks used in a given application. The section in the document above that describes the importance of avoiding address overlap should be looked at closely. In order to get a handle on the address range each framework requires (for a given application), you have to keep tabs on the size of the address space that each MachO file takes up. otool can peer into the inner workings of a framework and help you space each framework�s address range appropriately. MachOInfo is a tool that generates a report for a collection of frameworks.

MachOInfo outputs the base virtual memory address, the length of the address range and the headroom for each framework in the collection. The base virtual memory address is defined by setting the linker flag seg1addr for a given framework target. -seg1addr 0x10000000 assigns a base address of 0x10000000.

The address range starts at this base address. The length of the address range can change while the framework is being developed. In order to get the most out of MachOInfo, create a new directory in you project folder and place links to the frameworks you would like to prebind in a target. For example, if you have a target with two frameworks that you would like to prebind do the following: (WebApp is a project folder for an application named WebApp)

*build MachOInfo into a command line tool (target of type �tool�) named �machoinfo� *Create a new directory in your project folder named something like �WebAppFrameworkLinks�

• cd to the new directory *Place links to the two frameworks in the new directory *run machoinfo for the current directory

mkdir ~/Dev/WebApp/WebAppFrameworkLinks cd ~/Dev/WebApp/WebAppFrameworkLinks ln �s ~/bin/CustomWebKit.framework CustomWebKit.framework ln �s ~/bin/CustomAppKit.framework CustomAppKit.framework machoinfo .

outputs:

address length headroom name 0x10000000 0x000baef8 0x0ff45108 CustomWebKit
0x20000000 0x00003d40 unknown CustomAppKit

Just for fun, generate a report for /System/Library/Frameworks. Here�s the output for OS X v10.2.6.

address length headroom name 0x7e360000 0x000baef8 0x08e35108 WebKit
0x87250000 0x00003d40 0x0092c2c0 DVComponentGlue
0x87b80000 0x0000a0dc 0x04a35f24 DrawSprocket
0x8c5c0000 0x0000f32c 0x00050cd4 FWAUserLib
0x8c620000 0x0001fc84 0x0013037c AGL
0x8c770000 0x0000228c 0x0002dd74 AppKitScripting
0x8c7a0000 0x0000675c 0x008698a4 ExceptionHandling
0x8d010000 0x00002280 0x0004dd80 Scripting
0x8d060000 0x0001cfe4 0x02f8301c DiscRecordingUI
0x90000000 0x0013427c 0x00000000 System
0x90130000 0x000ee7e8 0x00271818 CoreFoundation
0x90490000 0x0007a2c4 0x000b5d3c IOKit
0x905c0000 0x00002278 0x0000dd88 CoreServices
0x905d0000 0x00070f04 0x0002f0fc IOBluetooth
0x90670000 0x0000228c 0x002fdd74 ApplicationServices 0x90970000 0x00010058 0x000cffa8 AppleTalk
0x90a50000 0x00025a20 0x0000a5e0 SystemConfiguration 0x90a80000 0x00002264 0x0000dd9c Carbon
0x90a90000 0x0002ad50 0x000052b0 OpenGL
0x90ac0000 0x00049020 0x00006fe0 AppleShareClientCore 0x90b10000 0x000338c0 0x0001c740 DirectoryService
0x90b60000 0x00009910 0x001366f0 JavaVM
0x90ca0000 0x0002a910 0x000056f0 AppleShareClient
0x90cd0000 0x00002260 0x0000dda0 Cocoa
0x90ce0000 0x000501f0 0x0000fe10 CoreMIDIServer
0x90d40000 0x000e8000 0x00068000 InterfaceBuilder
0x90e90000 0x0000bca4 0x0101435c ScreenSaver
0x91eb0000 0x00002910 0x000bd6f0 AudioUnit
0x91f70000 0x001bc0e4 0x00a73f1c QuickTime
0x92ba0000 0x003dd1a4 0x000f2e5c Security
0x93070000 0x006d1b28 0x00000000 AppKit
0x936e0000 0x0000f25c 0x00360da4 PCSC
0x93a50000 0x000fda7c 0x00322584 AddressBook
0x93e70000 0x00049b5c 0x001464a4 LDAP
0x94000000 0x00098ca4 0x0008735c DiscRecording
0x94120000 0x00018efc 0x00097104 PreferencePanes
0x941d0000 0x00015db0 0x0000a250 IOBluetoothUI
0x941f0000 0x00129040 0x00026fc0 Message
0x94340000 0x00170378 0x0000fc88 Kerberos
0x944c0000 0x000129d8 0x007dd628 TWAIN
0x94cb0000 0x000c24dc 0x0000db24 AudioToolbox
0x94d80000 0x000aa038 0x00195fc8 CoreAudio
0x94fc0000 0x0009d364 0x00302c9c GLUT
0x95360000 0x0007de28 0x00000000 AppleScriptKit
0x953d0000 0x00052b30 0x009cd4d0 CoreMIDI
0x95df0000 0x00017000 0x00b89000 JavaEmbedding
0x96990000 0x00004b08 0x0047b4f8 ForceFeedback
0x96e10000 0x009b2d44 0x0062d2bc vecLib
0x97df0000 0x00213140 unknown Foundation

A couple of frameworks overlap (zero headroom), but the frameworks that overlap do not appear to be frameworks that work together. –zootbobbalu