C in a Nutshell

961 Pages·2015·7.227 MB·English

by  Peter Prinz, Tony Crawford

SECOND EDITION
C in a Nutshell
Peter Prinz and Tony Crawford
C in a Nutshell, Second Edition
by Peter Prinz and Tony Crawford
Copyright © 2010 Peter Prinz, Tony Crawford. All rights reserved.
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January 2015: Second Edition
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ISBN: 063-6-920-03384-4
[?]
Table of Contents
Preface. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . xiii
• Part I. Language
1. Language Basics. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3
Characteristics of C 3
The Structure of C Programs 4
Source Files 6
Comments 8
Character Sets 9
Wide Characters and Multibyte Characters 10
Universal Character Names 13
Digraphs and Trigraphs 14
Identifiers 15
Identifier Name Spaces 17
Identifier Scope 18
How the C Compiler Works 20
The C Compiler’s Translation Phases 21
Tokens 23
2. Types. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 25
Typology 25
Integer Types 26
Integer Types Defined in Standard Headers 31
Floating-Point Types 33
Complex Floating-Point Types (C99) 35
Enumerated Types 36
The Type void 37
void in Function Declarations 38
Expressions of Type void 38
Pointers to void 38
iii
The Alignment of Objects in Memory 39
3. Literals. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 41
Integer Constants 41
Floating-Point Constants 42
Decimal Floating-Point Constants 42
Hexadecimal Floating-Point Constants 43
Character Constants 44
Types and Values of Character Constants 44
Escape Sequences 46
String Literals 48
4. Type Conversions. . . . . . . . . . . . . . . . . . . . . . . . . . . . . 53
Conversion of Arithmetic Types 54
Hierarchy of Types 54
Integer Promotion 55
Usual Arithmetic Conversions 56
Other Implicit Type Conversions 58
The Results of Arithmetic Type Conversions 59
Conversion of Nonarithmetic Types 63
Array and Function Designators 63
Explicit Pointer Conversions 65
Implicit Pointer Conversions 67
Conversions Between Pointer and Integer Types 70
5. Expressions and Operators. . . . . . . . . . . . . . . . . . . . . 73
How Expressions Are Evaluated 74
Generic Selections (C11) 74
Lvalues 75
Side Effects and Sequence Points 77
Operator Precedence and Associativity 78
Operators in Detail 79
Arithmetic Operators 80
Assignment Operators 83
Increment and Decrement Operators 86
Comparative Operators 88
Logical Operators 90
Bitwise Operators 91
Memory Addressing Operators 95
Other Operators 99
Constant Expressions 106
Integer Constant Expressions 106
Other Constant Expressions 107
6. Statements. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 109
iv Table of Contents
Expression Statements 109
Block Statements 110
Loops 111
while Statements 111
for Statements 112
do…while Statements 114
Nested Loops 115
Selection Statements 116
if Statements 116
switch Statements 117
Unconditional Jumps 119
The break Statement 119
The continue Statement 120
The goto Statement 121
The return Statement 123
7. Functions. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 125
Function Definitions 125
Functions and Storage Class Specifiers 126
K&R-Style Function Definitions 127
Function Parameters 128
Arrays as Function Parameters 128
The main() Function 130
Function Declarations 133
Declaring Optional Parameters 134
Declaring Variable-Length Array Parameters 134
How Functions Are Executed 135
Pointers as Arguments and Return Values 135
Inline Functions 137
Non-returning Functions 139
Recursive Functions 139
Variable Numbers of Arguments 141
8. Arrays. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 143
Defining Arrays 143
Fixed-Length Arrays 144
Variable-Length Arrays 144
Accessing Array Elements 145
Initializing Arrays 146
Writing Initialization Lists 147
Initializing Specific Elements 148
Strings 149
Multidimensional Arrays 151
Matrices 151
Declaring Multidimensional Arrays 152
Table of Contents v
Initializing Multidimensional Arrays 152
Arrays as Arguments of Functions 153
9. Pointers. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 157
Declaring Pointers 157
Null Pointers 159
void Pointers 159
Initializing Pointers 160
Operations with Pointers 161
Using Pointers to Read and Modify Objects 161
Modifying and Comparing Pointers 163
Pointers and Type Qualifiers 165
Constant Pointers and Pointers to Constant Objects 166
Restricted Pointers 167
Pointers to Arrays and Arrays of Pointers 169
Array Pointers 170
Pointer Arrays 171
Pointers to Functions 174
10. Structures and Unions and Bit-Fields. . . . . . . . . . . . . 177
Structures 177
Defining Structure Types 178
Structure Objects and typedef Names 179
Incomplete Structure Types 179
Accessing Structure Members 180
Initializing Structures 182
Initializing Specific Members 183
Structure Members in Memory 184
Flexible Structure Members 185
Pointers as Structure Members 186
Unions 189
Defining Union Types 189
Initializing Unions 191
Anonymous Structures and Unions 191
Bit-Fields 192
11. Declarations. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 195
Object and Function Declarations 196
Examples 197
Storage Class Specifiers 199
Type Qualifiers 200
Declarations and Definitions 202
Complex Declarators 203
Type Names 205
typedef Declarations 206
vi Table of Contents
_Static_assert Declarations 208
Linkage of Identifiers 209
External Linkage 209
Internal Linkage 209
No Linkage 210
Storage Duration of Objects 211
Static Storage Duration 211
Thread Storage Duration 211
Automatic Storage Duration 211
Initialization 212
Implicit Initialization 212
Explicit Initialization 212
12. Dynamic Memory Management. . . . . . . . . . . . . . . . . 215
Allocating Memory Dynamically 216
Characteristics of Allocated Memory 217
Resizing and Releasing Memory 218
An All-Purpose Binary Tree 220
Characteristics 220
Implementation 221
Generating an Empty Tree 223
Inserting New Data 224
Finding Data in the Tree 225
Removing Data from the Tree 226
Traversing a Tree 229
A Sample Application 230
13. Input and Output. . . . . . . . . . . . . . . . . . . . . . . . . . . . 233
Streams 234
Text Streams 234
Binary Streams 235
Files 235
File Position 236
Buffers 237
The Standard Streams 237
Opening and Closing Files 238
Opening a File 238
Access Modes 239
Closing a File 240
Reading and Writing 241
Byte-Oriented and Wide-Oriented Streams 241
Error Handling 242
Unformatted I/O 243
Formatted Output 249
Formatted Input 256
Table of Contents vii
Random File Access 262
Obtaining the Current File Position 262
Setting the File Access Position 263
14. Multithreading. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 267
Threads 268
Creating Threads 269
Other Thread Functions 271
Accessing Shared Data 273
Mutual Exclusion 274
Atomic Objects 276
Atomic Operations 276
Memory Ordering 278
Fences 280
Communication Between Threads: Condition Variables 280
Thread-local Objects and Thread-specific Storage 286
Using Thread-local Objects 286
Using Thread-specific Storage 287
15. Preprocessing Directives. . . . . . . . . . . . . . . . . . . . . . 291
Inserting the Contents of Header Files 292
How the Preprocessor Finds Header Files 293
Nested #include Directives 293
Defining and Using Macros 294
Macros Without Parameters 295
Macros with Parameters 296
Using Macros Within Macros 300
Macro Scope and Redefinition 302
Type-generic Macros 302
Conditional Compiling 303
The #if and #elif Directives 304
The defined Operator 304
The #ifdef and #ifndef Directives 305
Defining Line Numbers 305
Generating Error Messages 306
The #pragma Directive 306
The _Pragma Operator 307
Predefined Macros 308
Conditionally Defined Macros 309
• Part I. Standard Library
1. The Standard Headers. . . . . . . . . . . . . . . . . . . . . . . . 315
Using the Standard Headers 316
viii Table of Contents
Execution Environments 316
Function and Macro Calls 316
Reserved Identifiers 319
Functions with Bounds-Checking 320
Availability 320
Run-time Constraints 321
Contents of the Standard Headers 322
assert.h 322
complex.h 322
ctype.h 323
errno.h 324
fenv.h 325
float.h 326
inttypes.h 330
iso646.h 331
limits.h 332
locale.h 333
math.h 334
setjmp.h 336
signal.h 337
stdalign.h 338
stdarg.h 338
stdatomic.h 339
stdbool.h 341
stddef.h 342
stdint.h 343
stdio.h 345
stdlib.h 347
stdnoreturn.h 348
string.h 348
tgmath.h 349
threads.h 350
time.h 352
uchar.h 353
wchar.h 353
wctype.h 354
2. Functions at a Glance. . . . . . . . . . . . . . . . . . . . . . . . . 357
Input and Output 357
Mathematical Functions 359
Mathematical Functions for Integer Types 359
Floating-Point Functions 359
Function-like Macros 361
Pragmas for Arithmetic Operations 362
Table of Contents ix