Contents

OS X ABI Mach-O File Format Reference 4

Overview 4

Basic Structure 4

Header Structure and Load Commands 5

Segments 6

Sections 7

Data Types 9

Header Data Structure 9

Load Command Data Structures 16

Symbol Table and Related Data Structures 44

Relocation Data Structures 57

Universal Binaries and 32-bit/64-bit PowerPC Binaries 63

Document Revision History 67

2009-02-04 | Copyright © 2003, 2009 Apple Inc. All Rights Reserved.

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Figures and Tables

OS X ABI Mach-O File Format Reference 4

Figure 1 Mach-O file format basic structure 5

Table 1 The sections of a __TEXT segment 8

Table 2 The sections of a __DATA segment 8

Table 3 The sections of a __IMPORT segment 9

Table 4 Mach-O load commands 16

2009-02-04 | Copyright © 2003, 2009 Apple Inc. All Rights Reserved.

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