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Preface........................................................................................................................................ 6
Preface to the first edition .......................................................................................................... 8
Chapter 1 - A Tutorial Introduction ........................................................................................... 9
1.1 Getting Started.................................................................................................................. 9
1.2 Variables and Arithmetic Expressions........................................................................... 11
1.3 The for statement............................................................................................................ 16
1.4 Symbolic Constants........................................................................................................17
1.5 Character Input and Output............................................................................................ 18
1.5.1 File Copying............................................................................................................18
1.5.2 Character Counting ................................................................................................. 20
1.5.3 Line Counting.......................................................................................................... 21
1.5.4 Word Counting........................................................................................................22
1.6 Arrays............................................................................................................................. 23
1.7 Functions........................................................................................................................ 25
1.8 Arguments - Call by Value............................................................................................. 28
1.9 Character Arrays ............................................................................................................ 29
1.10 External Variables and Scope ......................................................................................31
Chapter 2 - Types, Operators and Expressions........................................................................ 35
2.1 Variable Names.............................................................................................................. 35
2.2 Data Types and Sizes ..................................................................................................... 35
2.3 Constants........................................................................................................................ 36
2.4 Declarations.................................................................................................................... 39
2.5 Arithmetic Operators......................................................................................................40
2.6 Relational and Logical Operators................................................................................... 40
2.7 Type Conversions........................................................................................................... 41
2.8 Increment and Decrement Operators.............................................................................. 44
2.9 Bitwise Operators........................................................................................................... 46
2.10 Assignment Operators and Expressions....................................................................... 47
2.11 Conditional Expressions............................................................................................... 49
2.12 Precedence and Order of Evaluation............................................................................ 49
Chapter 3 - Control Flow .........................................................................................................52
3.1 Statements and Blocks ...................................................................................................52
3.2 If-Else............................................................................................................................. 52
3.3 Else-If............................................................................................................................. 53
3.4 Switch............................................................................................................................. 54
3.5 Loops - While and For ................................................................................................... 56
3.6 Loops - Do-While...........................................................................................................58
3.7 Break and Continue........................................................................................................ 59
3.8 Goto and labels...............................................................................................................60
Chapter 4 - Functions and Program Structure.......................................................................... 62
4.1 Basics of Functions ........................................................................................................62
4.2 Functions Returning Non-integers ................................................................................. 65
4.3 External Variables.......................................................................................................... 67
4.4 Scope Rules.................................................................................................................... 72
4.5 Header Files.................................................................................................................... 73
4.6 Static Variables ..............................................................................................................75
4.7 Register Variables .......................................................................................................... 75
4.8 Block Structure............................................................................................................... 76
4.9 Initialization ................................................................................................................... 76
4.10 Recursion...................................................................................................................... 78
4.11 The C Preprocessor ......................................................................................................79
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4.11.1 File Inclusion.........................................................................................................79
4.11.2 Macro Substitution................................................................................................ 80
4.11.3 Conditional Inclusion............................................................................................ 82
Chapter 5 - Pointers and Arrays ............................................................................................... 83
5.1 Pointers and Addresses................................................................................................... 83
5.2 Pointers and Function Arguments.................................................................................. 84
5.3 Pointers and Arrays ........................................................................................................ 87
5.4 Address Arithmetic ........................................................................................................ 90
5.5 Character Pointers and Functions................................................................................... 93
5.6 Pointer Arrays; Pointers to Pointers............................................................................... 96
5.7 Multi-dimensional Arrays .............................................................................................. 99
5.8 Initialization of Pointer Arrays.....................................................................................101
5.9 Pointers vs. Multi-dimensional Arrays......................................................................... 101
5.10 Command-line Arguments......................................................................................... 102
5.11 Pointers to Functions.................................................................................................. 106
5.12 Complicated Declarations.......................................................................................... 108
Chapter 6 - Structures............................................................................................................. 114
6.1 Basics of Structures...................................................................................................... 114
6.2 Structures and Functions.............................................................................................. 116
6.3 Arrays of Structures .....................................................................................................118
6.4 Pointers to Structures ................................................................................................... 122
6.5 Self-referential Structures ............................................................................................ 124
6.6 Table Lookup ...............................................................................................................127
6.7 Typedef......................................................................................................................... 129
6.8 Unions .......................................................................................................................... 131
6.9 Bit-fields.......................................................................................................................132
Chapter 7 - Input and Output .................................................................................................135
7.1 Standard Input and Output ........................................................................................... 135
7.2 Formatted Output - printf............................................................................................. 137
7.3 Variable-length Argument Lists...................................................................................138
7.4 Formatted Input - Scanf................................................................................................ 140
7.5 File Access ...................................................................................................................142
7.6 Error Handling - Stderr and Exit.................................................................................. 145
7.7 Line Input and Output.................................................................................................. 146
7.8 Miscellaneous Functions.............................................................................................. 147
7.8.1 String Operations................................................................................................... 147
7.8.2 Character Class Testing and Conversion ..............................................................148
7.8.3 Ungetc ................................................................................................................... 148
7.8.4 Command Execution............................................................................................. 148
7.8.5 Storage Management............................................................................................. 148
7.8.6 Mathematical Functions........................................................................................ 149
7.8.7 Random Number generation .................................................................................149
Chapter 8 - The UNIX System Interface................................................................................ 150
8.1 File Descriptors ............................................................................................................ 150
8.2 Low Level I/O - Read and Write.................................................................................. 151
8.3 Open, Creat, Close, Unlink .......................................................................................... 152
8.4 Random Access - Lseek............................................................................................... 154
8.5 Example - An implementation of Fopen and Getc....................................................... 155
8.6 Example - Listing Directories ...................................................................................... 158
8.7 Example - A Storage Allocator.................................................................................... 162
Appendix A - Reference Manual ...........................................................................................167
A.1 Introduction ................................................................................................................. 167
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A.2 Lexical Conventions.................................................................................................... 167
A.2.1 Tokens .................................................................................................................. 167
A.2.2 Comments............................................................................................................. 167
A.2.3 Identifiers.............................................................................................................. 167
A.2.4 Keywords.............................................................................................................. 168
A.2.5 Constants.............................................................................................................. 168
A.2.6 String Literals....................................................................................................... 170
A.3 Syntax Notation........................................................................................................... 170
A.4 Meaning of Identifiers................................................................................................. 170
A.4.1 Storage Class........................................................................................................ 170
A.4.2 Basic Types ..........................................................................................................171
A.4.3 Derived types........................................................................................................ 172
A.4.4 Type Qualifiers.....................................................................................................172
A.5 Objects and Lvalues ....................................................................................................172
A.6 Conversions................................................................................................................. 172
A.6.1 Integral Promotion................................................................................................ 173
A.6.2 Integral Conversions............................................................................................. 173
A.6.3 Integer and Floating.............................................................................................. 173
A.6.4 Floating Types...................................................................................................... 173
A.6.5 Arithmetic Conversions........................................................................................ 173
A.6.6 Pointers and Integers ............................................................................................ 174
A.6.7 Void...................................................................................................................... 175
A.6.8 Pointers to Void.................................................................................................... 175
A.7 Expressions.................................................................................................................. 175
A.7.1 Pointer Conversion............................................................................................... 176
A.7.2 Primary Expressions............................................................................................. 176
A.7.3 Postfix Expressions ..............................................................................................176
A.7.4 Unary Operators ................................................................................................... 178
A.7.5 Casts ..................................................................................................................... 180
A.7.6 Multiplicative Operators....................................................................................... 180
A.7.7 Additive Operators ............................................................................................... 181
A.7.8 Shift Operators .....................................................................................................181
A.7.9 Relational Operators.............................................................................................182
A.7.10 Equality Operators.............................................................................................. 182
A.7.11 Bitwise AND Operator....................................................................................... 182
A.7.12 Bitwise Exclusive OR Operator ......................................................................... 183
A.7.13 Bitwise Inclusive OR Operator ..........................................................................183
A.7.14 Logical AND Operator....................................................................................... 183
A.7.15 Logical OR Operator.......................................................................................... 183
A.7.16 Conditional Operator.......................................................................................... 183
A.7.17 Assignment Expressions..................................................................................... 184
A.7.18 Comma Operator................................................................................................ 184
A.7.19 Constant Expressions ......................................................................................... 185
A.8 Declarations.................................................................................................................185
A.8.1 Storage Class Specifiers....................................................................................... 186
A.8.2 Type Specifiers.....................................................................................................187
A.8.3 Structure and Union Declarations ........................................................................187
A.8.4 Enumerations........................................................................................................190
A.8.5 Declarators............................................................................................................ 191
A.8.6 Meaning of Declarators........................................................................................ 192
A.8.7 Initialization..........................................................................................................195
A.8.8 Type names........................................................................................................... 197
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A.8.9 Typedef................................................................................................................. 198
A.8.10 Type Equivalence............................................................................................... 198
A.9 Statements ................................................................................................................... 198
A.9.1 Labeled Statements...............................................................................................199
A.9.2 Expression Statement ........................................................................................... 199
A.9.3 Compound Statement........................................................................................... 199
A.9.4 Selection Statements ............................................................................................200
A.9.5 Iteration Statements.............................................................................................. 200
A.9.6 Jump statements ...................................................................................................201
A.10 External Declarations ................................................................................................ 202
A.10.1 Function Definitions........................................................................................... 202
A.10.2 External Declarations......................................................................................... 203
A.11 Scope and Linkage ....................................................................................................204
A.11.1 Lexical Scope ..................................................................................................... 204
A.11.2 Linkage............................................................................................................... 205
A.12 Preprocessing............................................................................................................. 205
A.12.1 Trigraph Sequences............................................................................................ 206
A.12.2 Line Splicing ......................................................................................................206
A.12.3 Macro Definition and Expansion ....................................................................... 206
A.12.4 File Inclusion...................................................................................................... 208
A.12.5 Conditional Compilation.................................................................................... 209
A.12.6 Line Control ....................................................................................................... 210
A.12.7 Error Generation.................................................................................................210
A.12.8 Pragmas .............................................................................................................. 211
A.12.9 Null directive...................................................................................................... 211
A.12.10 Predefined names .............................................................................................211
A.13 Grammar.................................................................................................................... 211
Appendix B - Standard Library..............................................................................................219
B.1 Input and Output: <stdio.h> ........................................................................................ 219
B.1.1 File Operations ..................................................................................................... 219
B.1.2 Formatted Output.................................................................................................. 221
B.1.3 Formatted Input .................................................................................................... 222
B.1.4 Character Input and Output Functions.................................................................. 224
B.1.5 Direct Input and Output Functions....................................................................... 224
B.1.6 File Positioning Functions.................................................................................... 225
B.1.7 Error Functions..................................................................................................... 225
B.2 Character Class Tests: <ctype.h> ................................................................................ 225
B.3 String Functions: <string.h>........................................................................................ 226
B.4 Mathematical Functions: <math.h>.............................................................................227
B.5 Utility Functions: <stdlib.h> .......................................................................................228
B.6 Diagnostics: <assert.h>................................................................................................ 230
B.7 Variable Argument Lists: <stdarg.h>.......................................................................... 230
B.8 Non-local Jumps: <setjmp.h>...................................................................................... 231
B.9 Signals: <signal.h> ...................................................................................................... 231
B.10 Date and Time Functions: <time.h>.......................................................................... 232
B.11 Implementation-defined Limits: <limits.h> and <float.h>
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Appendix C - Summary of Changes ...................................................................................... 235
