ISO/IEC 14519:1999

Information technology — POSIX Ada Language Interfaces — Binding for System Application Program Interface (API) — Realtime Extensions

Technologies de l'information — Interfaces de langage POSIX Ada — Boucle pour interface de programme d'application système (API) — Extensions temps réel

General Information

• Status: Withdrawn
• Publication Date: 21-Apr-1999
• Withdrawal Date: 21-Apr-1999
• ICS: 35.060 - Languages used in information technology
• Technical Committee: ISO/IEC JTC 1/SC 22 - Programming languages, their environments and system software interfaces
• Drafting Committee: ISO/IEC JTC 1/SC 22 - Programming languages, their environments and system software interfaces
• Current Stage: 9599 - Withdrawal of International Standard
• Start Date: 20-Dec-2001
• Completion Date: 12-Feb-2026

Relations

• Revised: ISO/IEC 14519:2001 - Information technology — POSIX Ada Language Interfaces — Binding for System Application Program Interface (API)
• Effective Date: 15-Apr-2008

Standards Content (Sample)

INTERNATIONAL ISO/IEC
STANDARD 14519
ANSI/IEEE
Std 1003.5b
First edition
1999-04-01 ®
Information technology — POSIX Ada
Language Interfaces — Binding for System
Application Program Interface (API) —
Realtime Extensions ®
Technologies de l'information — Interfaces de langage POSIX Ada —
Boucle pour interface de programme d'application système (API) —
Extensions temps réel
Reference number
ANSI/IEEE
bc
Std 1003.5b, 1996 edition
Abstract: This standard is part of the POSIX series of standards for applications and user
interfaces to open systems. It defines the Ada language bindings as package specifications
and accompanying textual descriptions of the application program interface (API). This
standard supports application portability at the source code level through the binding be-
tween ISO 8652: 1987 (Ada) and ISO/IEC 9945-1: 1990 (IEEE Std 1003.1-1990) (POSIX),
as amended by IEEE Std 1003.1b-1993, IEEE Std 1003.1c-1995, and IEEE Std 1003.1i-
1995. Terminology and general requirements, process primitives, the process environment,
files and directories, input and output primitives, device- and class-specific functions, lan-
guage-specific services for Ada, system databases, synchronization, memory management,
execution scheduling, clocks and timers, and message passing are covered. It also specifies
behavior to support the binding that must be provided by the Ada compilation system.
Keywords: Ada, API, application portability, computer language bindings, open systems,
operating systems, portable application, POSIX, POSIX language bindings, real-time,
thread.
POSIX is a registered trademark of the Institute of Electrical and Electronics Engineers, Inc
The Institute of Electrical and Electronics Engineers, Inc.
345 East 47th Street, New York, NY 10017-2394, USA
Copyright ã 1999 by the
Institute of Electrical and Electronics Engineers, Inc.
All rights reserved. Published 1996.
Printed in the United States of America.
ISBN 0-7381-1570-3
No part of this publication may be reproduced in any form,
in an electronic retrieval system or otherwise,
without the prior written permission of the publisher.
18 March 1999 SH94726
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Contents
PAGE
Introduction . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . xi
Section 1: General . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1
1.1 Scope . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1
1.2 Normative References . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2
1.3 Conformance . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3
1.3.1 Implementation Conformance . . . . . . . . . . . . . . . . . . . 3
1.3.2 Application Conformance . . . . . . . . . . . . . . . . . . . . . 6
Section 2: Terminology and General Requirements . . . . . . . . . . . . . . . . 7
2.1 Editorial Conventions . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7
2.2 Definitions . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8
2.2.1 Terminology . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8
2.2.2 General Terms . . . . . . . . . . . . . . . . . . . . . . . . . . . . 10
2.2.3 Abbreviations . . . . . . . . . . . . . . . . . . . . . . . . . . . . 26
2.3 General Concepts . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 27
2.3.1 Process/Active Partition Relationship . . . . . . . . . . . . . . 27
2.3.2 Task/Thread Relationship . . . . . . . . . . . . . . . . . . . . . 27
2.3.3 Ada Character Differences . . . . . . . . . . . . . . . . . . . . . 27
2.3.4 Posix Signals Are Not Interrupts . . . . . . . . . . . . . . . . . 28
2.3.5 System Call Exception Errors . . . . . . . . . . . . . . . . . . . 28
2.3.6 Extended Security Controls . . . . . . . . . . . . . . . . . . . . 28
2.3.7 File Access Permissions . . . . . . . . . . . . . . . . . . . . . . 28
2.3.8 File Hierarchy . . . . . . . . . . . . . . . . . . . . . . . . . . . . 29
2.3.9 Filename Portability . . . . . . . . . . . . . . . . . . . . . . . . 29
2.3.10 File Times Update . . . . . . . . . . . . . . . . . . . . . . . . . 29
2.3.11 Pathname Resolution . . . . . . . . . . . . . . . . . . . . . . . . 30
2.3.12 Allocated Storage . . . . . . . . . . . . . . . . . . . . . . . . . . 31
2.4 PackagePOSIX. . . . . . . . . . . . . 31
2.4.1 Constants and Static Subtypes . . . . . . . . . . . . . . . . . . 36
2.4.2 POSIX Characters . . . . . . . . . . . . . . . . . . . . . . . . . 41
2.4.3 POSIX Strings . . . . . . . . . . . . . . . . . . . . . . . . . . . . 42
2.4.4 String Lists . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 43
2.4.5 Option Sets . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 45
2.4.6 Error Codes and Exceptions . . . . . . . . . . . . . . . . . . . . 46
2.4.7 System Identification . . . . . . . . . . . . . . . . . . . . . . . . 52
2.4.8 Time Types . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 53
2.5 PackagePOSIX_Options . . . . . . . . . . 55
2.5.1 Implementation Options . . . . . . . . . . . . . . . . . . . . . . 55
ii
2.6 PackagePOSIX_Limits . . . . . . . . . . . 58
2.6.1 Implementation Limits . . . . . . . . . . . . . . . . . . . . . . . 60
2.7 PackageAda_Streams . . . . . . . . . . . 64
2.8 PackageSystem . . . . . . . . . . . . 65
2.9 PackageSystem_Storage_Elements . . . . . . . . 66
2.10 PackagePOSIX_Page_Alignment . . . . . . . . 67
2.10.1 Description . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 67
2.10.2 Error Handling . . . . . . . . . . . . . . . . . . . . . . . . . . . 68
2.11 Environment Description . . . . . . . . . . . . . . . . . . . . . . . . . . . 68
2.11.1 Time-Zone Information . . . . . . . . . . . . . . . . . . . . . . . 69
Section 3: Process Primitives . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 71
3.1 PackagePOSIX_Process_Primitives . . . . . . . 71
3.1.1 Process Template . . . . . . . . . . . . . . . . . . . . . . . . . . 73
3.1.2 Process Creation . . . . . . . . . . . . . . . . . . . . . . . . . . 75
3.1.3 Process Exit . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 79
3.1.4 Termination Status . . . . . . . . . . . . . . . . . . . . . . . . . 80
3.1.5 Wait for Process Termination . . . . . . . . . . . . . . . . . . . 82
3.2 PackagePOSIX_Unsafe_Process_Primitives . . . . . . . 84
3.2.1 Process Creation . . . . . . . . . . . . . . . . . . . . . . . . . . 85
3.2.2 File Execution . . . . . . . . . . . . . . . . . . . . . . . . . . . . 87
3.3 PackagePOSIX_Signals . . . . . . . . . . 91
3.3.1 Signal Model . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 94
3.3.2 Signal Type . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 98
3.3.3 Standard Signals . . . . . . . . . . . . . . . . . . . . . . . . . . 98
3.3.4 Default Signal Actions . . . . . . . . . . . . . . . . . . . . . . . 102
3.3.5 Tasking Safety . . . . . . . . . . . . . . . . . . . . . . . . . . . . 103
3.3.6 Interruptibility . . . . . . . . . . . . . . . . . . . . . . . . . . . 103
3.3.7 Signal Sets . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 105
3.3.8 Block and Unblock Signals . . . . . . . . . . . . . . . . . . . . . 106
3.3.9 Ignore Signals . . . . . . . . . . . . . . . . . . . . . . . . . . . . 107
3.3.10 Controlling Generation of Signal for Child Process . . . . . . . 108
3.3.11 Examine Pending Signals . . . . . . . . . . . . . . . . . . . . . 109
3.3.12 Signal Event Notification . . . . . . . . . . . . . . . . . . . . . 109
3.3.13 Signal Information . . . . . . . . . . . . . . . . . . . . . . . . . 110
3.3.14 Control Signal Queueing . . . . . . . . . . . . . . . . . . . . . . 112
3.3.15 Wait for Signal . . . . . . . . . . . . . . . . . . . . . . . . . . . . 113
3.3.16 Wait for Signal with Information . . . . . . . . . . . . . . . . . 115
3.3.17 Signal Entries . . . . . . . . . . . . . . . . . . . . . . . . . . . . 116
3.3.18 Send a Signal . . . . . . . . . . . . . . . . . . . . . . . . . . . . 118
3.3.19 Queue a Signal . . . . . . . . . . . . . . . . . . . . . . . . . . . 119
3.3.20 Interrupt a Task . . . . . . . . . . . . . . . . . . . . . . . . . . . 120
Section 4: Process Environment . . . . . . . . . . . . . . . . . . . . . . . . . . . 123
4.1 PackagePOSIX_Process_Identification . . . . . . 123
4.1.1 Process Identification Operations . . . . . . . . . . . . . . . . . 124
4.1.2 Process Group Identification . . . . . . . . . . . . . . . . . . . . 125
4.1.3 User Identification . . . . . . . . . . . . . . . . . . . . . . . . . 127
iii
4.1.4 User and Group Identification . . . . . . . . . . . . . . . . . . . 128
4.2 PackagePOSIX_Process_Times . . . . . . . . . 130
4.2.1 Process Time Accounting . . . . . . . . . . . . . . . . . . . . . . 130
4.3 PackagePOSIX_Process_Environment . . . . . . . 132
4.3.1 Argument List . . . . . . . . . . . . . . . . . . . . . . . . . . . . 133
4.3.2 Environment Variables . . . . . . . . . . . . . . . . . . . . . . . 133
4.3.3 Process Working Directory . . . . . . . . . . . . . . . . . . . . . 137
4.4 PackagePOSIX_Calendar . . . . . . . . . . 138
4.4.1 Time Information . . . . . . . . . . . . . . . . . . . . . . . . . . 139
4.4.2 Operations on POSIX Times . . . . . . . . . . . . . . . . . . . . 140
4.5 PackagePOSIX_Configurable_System_Limits . . . . . 142
4.5.1 Get Configurable System Options . . . . . . . . . . . . . . . . . 143
4.5.2 Get Configurable System Limits . . . . . . . . . . . . . . . . . 145
Section 5: Files and Directories . . . . . . . . . . . . . . . . . . . . . . . . . . . . 149
5.1 PackagePOSIX_Permissions . . . . . . . . . 149
5.1.1 File Permissions . . . . . . . . . . . . . . . . . . . . . . . . . . . 150
5.1.2 Process Permission Set . . . . . . . . . . . . . . . . . . . . . . . 151
5.2 PackagePOSIX_Files . . . . . . . . . . . 152
5.2.1 Create and Remove Files . . . . . . . . . . . . . . . . . . . . . . 153
5.2.2 Inquiries on File Types . . . . . . . . . . . . . . . . . . . . . . . 156
5.2.3 Modify File Pathnames . . . . . . . . . . . . . . . . . . . . . . . 156
5.2.4 Directory Iteration . . . . . . . . . . . . . . . . . . . . . . . . . 159
5.2.5 Update File Status Information . . . . . . . . . . . . . . . . . . 161
5.2.6 Check File Accessibility . . . . . . . . . . . . . . . . . . . . . . 163
5.3 PackagePOSIX_File_Status . . . . . . . . . 164
5.3.1 Access File Status . . . . . . . . . . . . . . . . . . . . . . . . . . 165
5.3.2 Access Status Information . . . . . . . . . . . . . . . . . . . . . 166
5.4 PackagePOSIX_Configurable_File_Limits . . . . . . . 168
5.4.1 File Limits . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 170
5.4.2 File Restrictions . . . . . . . . . . . . . . . . . . . . . . . . . . . 174
5.4.3 Pathname-Specific Options . . . . . . . . . . . . . . . . . . . . 176
Section 6: Input and Output Primitives . . . . . . . . . . . . . . . . . . . . . . . 179
6.1 PackagePOSIX_IO . . . . . . . . . . . . 179
6.1.1 Open or Create a File . . . . . . . . . . . . . . . . . . . . . . . . 181
6.1.2 I/O Buffer Type . . . . . . . . . . . . . . . . . . . . . . . . . . . 187
6.1.3 Read from a File . . . . . . . . . . . . . . . . . . . . . . . . . . . 187
6.1.4 Write to a File . . . . . . . . . . . . . . . . . . . . . . . . . . . . 190
6.1.5 File Position Operations . . . . . . . . . . . . . . . . . . . . . . 195
6.1.6 Terminal Operations . . . . . . . . . . . . . . . . . . . . . . . . 196
6.1.7 File Control . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 196
6.1.8 Update File Status Information . . . . . . . . . . . . . . . . . . 198
6.1.9 Truncate File to A Specified Length . . . . . . . . . . . . . . . 199
6.1.10 Synchronize a File’s State . . . . . . . . . . . . . . . . . . . . . 200
6.1.11 Data Synchronization . . . . . . . . . . . . . . . . . . . . . . . 201
6.2 PackagePOSIX_File_Locking . . . . . . . . . 202
6.2.1 Lock and Unlock a Region of a File . . . . . . . . . . . . . . . . 203
iv
6.3 PackagePOSIX_Asynchronous_IO . . . . . . . . 204
6.3.1 AIO Descriptor Type . . . . . . . . . . . . . . . . . . . . . . . . 206
6.3.2 Attributes of AIO Control Blocks . . . . . . . . . . . . . . . . . 208
6.3.3 Asynchronous Read . . . . . . . . . . . . . . . . . . . . . . . . . 211
6.3.4 Asynchronous Write . . . . . . . . . . . . . . . . . . . . . . . . 212
6.3.5 List Directed I/O . . . . . . . . . . . . . . . . . . . . . . . . . . 214
6.3.6 Retrieve Status of Asynchronous I/O Request . . . . . . . . . . 216
6.3.7 Retrieve Bytes Transferred by Asynchronous I/O Request . . 218
6.3.8 Cancel Asynchronous I/O Request . . . . . . . . . . . . . . . . 219
6.3.9 Wait for Asynchronous I/O Request to Complete . . . . . . . . 220
6.3.10 Asynchronous File and Data Synchronization . . . . . . . . . . 221
Section 7: Device- and Class-Specific Functions . . . . . . . . . . . . . . . . . . 225
7.1 General Terminal Interface . . . . . . . . . . . . . . . . . . . . . . . . . 225
7.1.1 Interface Characteristics . . . . . . . . . . . . . . . . . . . . . . 225
7.2 PackagePOSIX_Terminal_Functions . . . . . . . 232
7.2.1 Terminal Characteristics . . . . . . . . . . . . . . . . . . . . . . 234
7.2.2 Input Modes . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 237
7.2.3 Output Modes . . . . . . . . . . . . . . . . . . . . . . . . . . . . 239
7.2.4 Control Modes . . . . . . . . . . . . . . . . . . . . . . . . . . . . 239
7.2.5 Local Modes . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 240
7.2.6 Retrieve and Define Terminal Modes and Bits per Character . 242
7.2.7 Special Control Characters . . . . . . . . . . . . . . . . . . . . 243
7.2.8 Noncanonical Controls . . . . . . . . . . . . . . . . . . . . . . . 245
7.2.9 Baud Rate Subprograms . . . . . . . . . . . . . . . . . . . . . . 245
7.2.10 Line Control Operations . . . . . . . . . . . . . . . . . . . . . . 246
7.2.11 Foreground Process Group ID . . . . . . . . . . . . . . . . . . . 248
7.2.12 Generate Terminal Pathname . . . . . . . . . . . . . . . . . . . 249
Section 8: Language-Specific Services for Ada . . . . . . . . . . . . . . . . . . . 251
8.1 Interoperable Ada I/O Services . . . . . . . . . . . . . . . . . . . . . . . 251
8.1.1 Requirements . . . . . . . . . . . . . . . . . . . . . . . . . . . . 251
8.1.2 Additional Interpretation of the POSIX.1 Standard . . . . . . 255
8.2 PackagePOSIX_Supplement_to_Ada_IO . . . . . . . 256
8.2.1 Parse Form values . . . . . . . . . . . . . . . . . . . . . . . . . . 257
8.2.2 Flush Files . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 258
Section 9: System Databases . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 259
9.1 PackagePOSIX_User_Database . . . . . . . . . 259
9.1.1 Access Contents of a User Database Item . . . . . . . . . . . . 259
9.1.2 Access User Database Items . . . . . . . . . . . . . . . . . . . . 260
9.2 PackagePOSIX_Group_Database . . . . . . . . 261
9.2.1 Access Contents of a Group Database Item . . . . . . . . . . . 262
9.2.2 Access Elements of the Group Item List of Members . . . . . . 262
9.2.3 Access Group Database Items . . . . . . . . . . . . . . . . . . . 263
Section 10: Data Interchange Format . . . . . . . . . . . . . . . . . . . . . . . . 265
Section 11: Synchronization . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 267
v
11.1 PackagePOSIX_Semaphores . . . . . . . . . . . 267
11.1.1 Semaphore and Semaphore Descriptor Types . . . . . . . . . . 268
11.1.2 Initialize an Unnamed Semaphore . . . . . . . . . . . . . . . . 269
11.1.3 Finalize an Unnamed Semaphore . . . . . . . . . . . . . . . . . 270
11.1.4 Create/Open a Named Semaphore . . . . . . . . . . . . . . . . 271
11.1.5 Close a Named Semaphore . . . . . . . . . . . . . . . . . . . . 273
11.1.6 Remove a Named Semaphore . . . . . . . . . . . . . . . . . . . 274
11.1.7 Decrement a Semaphore . . . . . . . . . . . . . . . . . . . . . . 275
11.1.8 Increment a Semaphore . . . . . . . . . . . . . . . . . . . . . . 276
11.1.9 Get the Value of a Semaphore . . . . . . . . . . . . . . . . . . . 276
11.2 PackagePOSIX_Mutexes . . . . . . . . . . 277
11.2.1 Mutex Ownership. . . . . . . . . . 278
11.2.2 Mutex and Mutex Descriptor Types . . . . . . . . . . . . . . . 279
11.2.3 Mutex Attributes Type . . . . . . . . . . . . . . . . . . . . . . . 279
11.2.4 Mutex Process Shared Attribute . . . . . . . . . . . . . . . . . 280
11.2.5 Mutex Locking Policy Attributes . . . . . . . . . . . . . . . . . 281
11.2.6 Initialize and Finalize a Mutex . . . . . . . . . . . . . . . . . . 283
11.2.7 Change the Ceiling Priority of a Mutex . . . . . . . . . . . . . 285
11.2.8 Lock and Unlock a Mutex . . . . . . . . . . . . . . . . . . . . . 286
11.3 PackagePOSIX_Condition_Variables . . . . . . . 287
11.3.1 Condition and Condition Descriptor Types . . . . . . . . . . . 288
11.3.2 Condition Variable Attributes Type . . . . . . . . . . . . . . . . 288
11.3.3 Condition Process Shared Attribute . . . . . . . . . . . . . . . 289
11.3.4 Initialize and Finalize a Condition . . . . . . . . . . . . . . . . 290
11.3.5 Broadcast and Signal a Condition . . . . . . . . . . . . . . . . 292
11.3.6 Wait on a Condition . . . . . . . . . . . . . . . . . . . . . . . . . 293
Section 12: Memory Management . . . . . . . . . . . . . . . . . . . . . . . . . . 295
12.1 PackagePOSIX_Memory_Locking . . . . . . . . 296
12.1.1 Lock/Unlock a Process’s Address Space . . . . . . . . . . . . . 296
12.2 PackagePOSIX_Memory_Range_Locking. . . . . . . 298
12.2.1 Lock/Unlock a Range of Process Address Space . . . . . . . . . 298
12.3 PackagePOSIX_Memory_Mapping . . . . . . . . 300
12.3.1 Map Process Addresses to a Memory Object . . . . . . . . . . . 301
12.3.2 Unmap Memory . . . . . . . . . . . . . . . . . . . . . . . . . . . 305
12.3.3 Change Memory Protection . . . . . . . . . . . . . . . . . . . . 306
12.3.4 Memory Object Synchronization . . . . . . . . . . . . . . . . . 308
12.4 PackagePOSIX_Shared_Memory_Objects . . . . . . . 309
12.4.1 Open a Shared Memory Object . . . . . . . . . . . . . . . . . . 310
12.4.2 Remove a Shared Memory Object . . . . . . . . . . . . . . . . . 312
12.5 PackagePOSIX_Generic_Shared_Memory . . . . . . . 313
12.5.1 Open Shared Memory . . . . . . . . . . . . . . . . . . . . . . . 314
12.5.2 Access Shared Memory . . . . . . . . . . . . . . . . . . . . . . . 317
12.5.3 Close Shared Memory . . . . . . . . . . . . . . . . . . . . . . . 317
12.5.4 Remove Shared Memory . . . . . . . . . . . . . . . . . . . . . . 318
12.5.5 Lock/Unlock Shared Memory . . . . . . . . . . . . . . . . . . . 318
Section 13: Execution Scheduling . . . . . . . . . . . . . . . . . . . . . . . . . . . 321
vi
13.1 Scheduling Concepts and Terminology . . . . . . . . . . . . . . . . . . . 321
13.2 PackagePOSIX_Process_Scheduling . . . . . . . 321
13.2.1 Scheduling Parameters . . . . . . . . . . . . . . . . . . . . . . . 322
13.2.2 Scheduling Policies . . . . . . . . . . . . . . . . . . . . . . . . . 323
13.2.3 Modify Process Scheduling Policy and Parameters . . . . . . . 323
13.2.4 Process Yield CPU . . . . . . . . . . . . . . . . . . . . . . . . . 325
13.2.5 Get Scheduling Limits . . . . . . . . . . . . . . . . . . . . . . . 325
13.3 Task Scheduling. . . . . . . . . . . . 326
13.3.1 Dynamic Priorities . . . . . . . . . . . . . . . . . . . . . . . . . 326
13.3.2 Task Dispatching Policy Pragma . . . . . . . . . . . . . . . . . 326
13.3.3 Task Creation Attributes Pragma . . . . . . . . . . . . . . . . . 327
13.3.4 Task Yield CPU . . . . . . . . . . . . . . . . . . . . . . . . . . . 327
13.4 Synchronization Scheduling . . . . . . . . . . . . . . . . . . . . . . . . . 328
Section 14: Clocks and Timers . . . . . . . . . . . . . . . . . . . . . . . . . . . . 329
14.1 PackagePOSIX_Timers . . . . . . . . . . . 329
14.1.1 Clock and Timer Types . . . . . . . . . . . . . . . . . . . . . . . 330
14.1.2 Realtime Clock . . . . . . . . . . . . . . . . . . . . . . . . . . . 330
14.1.3 Timer State and Timer Options . . . . . . . . . . . . . . . . . . 331
14.1.4 Clock Operations . . . . . . . . . . . . . . . . . . . . . . . . . . 332
14.1.5 Create a Timer . . . . . . . . . . . . . . . . . . . . . . . . . . . 333
14.1.6 Delete a Timer . . . . . . . . . . . . . . . . . . . . . . . . . . . . 335
14.1.7 Timer Operations . . . . . . . . . . . . . . . . . . . . . . . . . . 335
14.2 High Resolution Delay . . . . . . . . . . . . . . . . . . . . . . . . . . . . 338
Section 15: Message Passing . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 339
15.1 PackagePOSIX_Message_Queues . . . . . . . . 339
15.1.1 Message Queue Attributes . . . . . . . . . . . . . . . . . . . . . 341
15.1.2 Open a Message Queue . . . . . . . . . . . . . . . . . . . . . . . 343
15.1.3 Close a Message Queue . . . . . . . . . . . . . . . . . . . . . . . 346
15.1.4 Remove a Message Queue . . . . . . . . . . . . . . . . . . . . . 347
15.1.5 Send a Message to a Message Queue . . . . . . . . . . . . . . . 348
15.1.6 Receive a Message from a Message Queue . . . . . . . . . . . . 349
15.1.7 Generic Message Passing . . . . . . . . . . . . . . . . . . . . . 350
15.1.8 Notify Process that a Message is Available . . . . . . . . . . . 352
15.1.9 Set/Query Message Queue Attributes . . . . . . . . . . . . . . 353
Section 16: Task Management . . . . . . . . . . . . . . . . . . . . . . . . . . . . 355
16.1 PackageAda_Task_Identification . . . . . . . . 355
16.1.1 Description . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 355
Annex A (informative) Bibliography . . . . . . . . . . . . . . . . . . . . . . . . . 357
Annex B (informative) Rationale and Notes . . . . . . . . . . . . . . . . . . . . . 359
B.1 General . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 359
B.1.1 Purpose and Audience . . . . . . . . . . . . . . . . . . . . . . . 359
B.1.2 Relation to Other POSIX Standards . . . . . . . . . . . . . . . 359
B.1.3 Ada Language . . . . . . . . . . . . . . . . . . . . . . . . . . . . 360
B.1.4 Implementation Model . . . . . . . . . . . . . . . . . . . . . . . 361
vii
B.1.5 Level of Binding . . . . . . . . . . . . . . . . . . . . . . . . . . . 361
B.1.6 Form of Document . . . . . . . . . . . . . . . . . . . . . . . . . 362
B.1.7 Global Issues . . . . . . . . . . . . . . . . . . . . . . . . . . . . 363
B.1.8 Naming . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 364
B.1.9 Mapping C Features to Ada . . . . . . . . . . . . . . . . . . . . 365
B.1.10 Conformance . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 370
B.2 Terminology and General Requirements . . . . . . . . . . . . . . . . . . 370
B.2.1 Conventions . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 370
B.2.2 Definitions . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 370
B.2.3 General Concepts . . . . . . . . . . . . . . . . . . . . . . . . . . 371
B.2.4 Package POSIX . . . . . . . . . . . 374
B.2.5 Package POSIX_Options . . . . . . . . 380
B.2.6 Package POSIX_Limits . . . . . . . . . 381
B.2.7 Package Ada_Streams . . . . . . . . . 381
B.2.8 Package System. . . . . . . . . . . 381
B.2.9 Package System_Storage_Elements . . . . . . 381
B.2.10 Package POSIX_Page_Alignment . . . . . . . 381
B.2.11 Environment Description . . . . . . . . . . . . . . . . . . . . . 382
B.3 Process Primitives . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 382
B.3.1 Package POSIX_Process_Primitives . . . . . . . 382
B.3.2 Process Creation . . . . . . . . . . . . . . . . . . . . . . . . . . 383
B.3.3 Process Exit . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 384
B.3.4 Wait for Process Termination . . . . . . . . . . . . . . . . . . . 386
B.3.5 Package POSIX_Unsafe_Process_Primitives. . . . 386
B.3.6 Package POSIX_Signals . . . . . . . . 386
B.3.7 Signal Model . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 387
B.3.8 Signal Masking and Related Concepts . . . . . . . . . . . . . . 387
B.3.9 Tasking Safety . . . . . . . . . . . . . . . . . . . . . . . . . . . . 391
B.3.10 Signal Type . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 392
B.3.11 Standard Signals . . . . . . . . . . . . . . . . . . . . . . . . . . 392
B.3.12 Signal Sets . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 393
B.3.13 Examine and Change Signal Action . . . . . . . . . . . . . . . 393
B.3.14 Signal Queueing . . . . . . . . . . . . . . . . . . . . . . . . . . . 394
B.3.15 Signal Notification Model . . . . . . . . . . . . . . . . . . . . . 395
B.3.16 Examine Pending Signals . . . . . . . . . . . . . . . . . . . . . 396
B.3.17 Send a Signal . . . . . . . . . . . . . . . . . . . . . . . . . . . . 396
B.3.18 Binding for sigsuspend . . . . . . . . . 396
B.3.19 Synchronously Accept a Signal . . . . . . . . . . . . . . . . . . 396
B.3.20 Queue a Signal to a Process . . . . . . . . . . . . . . . . . . . . 397
B.3.21 Send a Signal to a Thread . . . . . . . . . . . . . . . . . . . . . 397
B.3.22 Schedule Alarm . . . . . . . . . . . . . . . . . . . . . . . . . . . 398
B.3.23 Suspend Process Execution . . . . . . . . . . . . . . . . . . . . 398
B.3.24 Delay Process Execution . . . . . . . . . . . . . . . . . . . . . . 398
B.3.25 Task Signal Entries . . . . . . . . . . . . . . . . . . . . . . . . . 398
B.3.26 Composability Considerations . . . . . . . . . . . . . . . . . . . 399
B.4 Process Environment . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 400
B.4.1 Organization . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 400
B.4.2 Package POSIX_Process_Identification . . . . 400
viii
B.4.3 Package Process_Times . . . . . . . . 401
B.4.4 Package POSIX_Process_Environment . . . . . 402
B.4.5 Package POSIX_Calendar. . . . . . . . 404
B.4.6 Package POSIX_Configurable_System_Limits . . . 405
B.5 Files and Directories . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 405
B.5.1 Organization . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 405
B.5.2 Package POSIX_Permissions . . . . . . . 406
B.5.3 Package POSIX_Files . . . . . . . . . 407
B.5.4 Package POSIX_File_Status . . . . . . . 408
B.5.5 Package POSIX_Configurable_File_Limits . . . . 408
B.5.6 Directory Operations . . . . . . . . . . . . . . . . . . . . . . . . 409
B.6 Input and Output Primitives . . . . . . . . . . . . . . . . . . . . . . . . 409
B.6.1 Package POSIX_IO . . . . . . . . . . 409
B.6.2 Package POSIX_File_Locking . . . . . . . 414
B.6.3 Package POSIX_Asynchronous_IO . . . . . . 415
B.7 Device- and Class-Specific Functions . . . . . . . . . . . . . . . . . . . . 417
B.8 Language-Specific Services for Ada . . . . . . . . . . . . . . . . . . . . . 418
B.8.1 General Rationale . . . . . . . . . . . . . . . . . . . . . . . . . . 418
B.8.2 Limitations on Interoperability . . . . . . . . . . . . . . . . . . 420
B.8.3 Rationale for Form Parameter . . . . . . . . . . . . . . . . . . . 421
B.8.4 Unaffected Implementation Dependencies . . . . . . . . . . . . 426
B.8.5 Notes on Specific Topics . . . . . . . . . . . . . . . . . . . . . . 426
B.9 System Databases . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 428
B.9.1 Requirements from POSIX.1 . . . . . . . . . . . . . . . . . . . 428
B.9.2 Rationale for the Current Design . . . . . . . . . . . . . . . . . 429
B.10 Data Interchange Format . . . . . . . . . . . . . . . . . . . . . . . . . . 430
B.11 Synchronization . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 430
B.11.1 Package POSIX_Semaphores . . . . . . . . 430
B.11.2 Mutexes & Condition Variables . . . . . . . . . . . . . . . . . . 433
B.12 Memory Management . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 436
B.12.1 Process Memory Locking . . . . . . . . . . . . . . . . . . . . . . 436
B.12.2 Package POSIX_Memory_Mapping . . . . . . . 437
B.12.3 Package POSIX_Shared_Memory_Objects . . . . . 438
B.12.4 Package POSIX_Generic_Shared_Memory . . . . . 439
B.13 Priority Process Scheduling . . . . . . . . . . . . . . . . . . . . . . . . . 441
B.13.1 Scheduling Concepts and Terminology . . . . . . . . . . . . . . 442
B.13.2 Package POSIX_Process_Scheduling . . . . . . . 442
B.13.3 Task Scheduling . . . . . . . . . . . . . . . . . . . . . . . . . . . 443
B.13.4 Synchronization Scheduling . . . . . . . . . . . . . . . . . . . . 444
B.13.5 Thread Scheduling Pragmas vs. Environment Variables . . . 445
B.14 Clocks and Timers . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 446
B.14.1 Types and Constants . . . . . . . . . . . . . . . . . . . . . . . . 446
B.14.2 Clock Operations . . . . . . . . . . . . . . . . . . . . . . . . . . 447
B.14.3 Timer Creation . . . . . . . . . . . . . . . . . . . . . . . . . . . 447
B.14.4 Timer Operations . . . . . . . . . . . . . . . . . . . . . . . . . . 447
B.14.5 High Resolution Sleep . . . . . . . . . . . . . . . . . . . . . . . 448
B.15 Message Passing . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 448
B.15.1 Message Queue Attributes . . . . . . . . . . . . . . . . . . . . . 449
ix
B.15.2 Priorities . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 449
B.15.3 Generic Message Passing . . . . . . . . . . . . . . . . . . . . . 449
B.15.4 Notification . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 450
B.16 Task Identification . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 450
B.17 Thread-Specific Data . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 450
Annex C (informative) Ada/C Cross-References . . . . . . . . . . . . . . . . . . . 451
C.1 Ada-to-C Cross-Reference . . . . . . . . . . . . . . . . . . . . . . . . . . 451
C.2 C-to-Ada Cross-Reference . . . . . . . . . . . . . . . . . . . . . . . . . . 469
Alphabetic Topical Index . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 489
TABLES
Table2.1 – Typographical Conventions . . . . . . . . . . . . . . . . . . . . . . . . 7
Table2.2 – Constant and Subtype Correspondences . . . . . . . . . . . . . . . . 37
Table2.3 – Option Set Comparisons . . . . . . . . . . . . . . . . . . . . . . . . . . 46
Table2.4 – Static Subtypes and Options . . . . . . . . . . . . . . . . . . . . . . . 59
Table2.5 – Portable Constants and Limits . . . . . . . . . . . . . . . . . . . . . . 63
Table2.6 – Static Subtypes and Limits . . . . . . . . . . . . . . . . . . . . . . . . 64
Table3.1 – Default Actions for Job Control Signals . . . . . . . . . . . . . . . . . 103
Table4.1 – Functions for System-Wide Options . . . . . . . . . . . . . . . . . . . 145
Table4.2 – Configurable System Limits . . . . . . . . . . . . . . . . . . . . . . . 146
Table6.1 – Standard File Descriptors . . . . . . . . . . . . . . . . . . . . . . . . . 182
Table6.2 – Error Codes and AIO Status Values . . . . . . . . . . . . . . . . . . . 217
Table7.1 –Terminal_Characteristics Components . . . . . . . . . . . . . . 235
Table7.2 –Terminal_Modes Values for Input Control . . . . . . . . . . . . . . 237
Table7.3 –Terminal_Modes Values for Output Control . . . . . . . . . . . . . 239
Table7.4 –Terminal_Modes Values for Hardware Control . . . . . . . . . . . . 240
Table7.5 –Terminal_Modes Values for Local Control Modes . . . . . . . . . . 241
Table7.6 – Special Control Character Usage . . . . . . . . . . . . . . . . . . . . . 244
x
International Standard ISO/IEC 14519:1999(E)
ISO (the International Organization for Standardization) and IEC (the International
Electrotechnical Commission) form the specialized system for worldwide standardization.
National bodies that are members of ISO or IEC participate in the development of International
Standards through technical committees established by the respective organization to deal with
particular fields of technical activity. ISO and IEC technical committees collaborate in fields of
mutual interest. Other international organizations, governmental and non-governmental, in
liaison with ISO and IEC, also take part in the work.
In the field of information technology, ISO and IEC have established a joint technical committee,
ISO/IEC JTC 1. Draft International Standards adopted by the joint technical committee are
circulated to national bodies for voting. Publication as an International Standard requires
approval by at least 75 % of the national bodies casting a vote.
International Standard ISO/IEC 14519 was prepared by Joint Technical Committee
ISO/IEC JTC 1, Information technology, Subcommittee SC 22, Programming languages, their
environments and system software interfaces.
Annexes A to C of this International Standard are for information only.
B C
International Organization for Standardization/International Electrotechnical Commission
Case postale 56 • CH-1211 Genève 20 • Switzerland
xi
Introduction
1 (This introductionis not a part of IEEE Std 1003.5b-1996, IEEE Standard for Information Technology—
2 POSIX Ada Language Interfaces—Part 1: Binding for System Application Program Interface (API)
3 Amendment 1: Realtime Extensions but is included for information only.)
4 This standard is an amended version of IEEE Std 1003.5-1992. The basic goal of
5 this standard is to provide an Ada application program interface for the language-
6 independent services made accessible to C-language applications programs by the
7 interfaces defined in ISO/IEC 9945-1: 1990 (IEEE Std 1003.1-1990), as amended by
8 IEEE Std 1003.1b-1993, IEEE Std 1003.1c-1995, and IEEE Std 1003.1i-1995.
9 The intent is to support portability of Ada applications via a standard binding to
10 the services provided by a POSIX-conforming operating system. POSIX is defined
11 by the standard C-language interfaces cited above. Therefore, much of the work in
12 producing this standard was deciding what features of those C-language interfaces
13 represented POSIX functionality, as opposed to C-language specific features.
14 This standard provides package specifications and accompanying textual description
15 for a set of Ada packages that represent the POSIX system. This standard also spec-
16 ifies behavior to support the binding that must be provided by the Ada compilation
17 system, and further defines behavior specified as implementation defined in the Ada
18 Language standard (particularly in the area of Text_IO) for use in a POSIX envi-
19 ronment.
20 The emphasis in POSIX is on application program portability, so the interfaces in this
21 standard are not sufficient to implement an Ada compilation system or a POSIX shell
22 (as defined in IEEE Std 1003.2-1992). For an application, the intent is that a Strictly
23 Conforming POSIX.5 Application (one that uses only the facilities in this standard
24 and that does not depend on implementation defined behavior) can be ported to any
25 Conforming Implementation of these interfaces, and that the binding makes it easy
26 to identify where a program is not strictly conforming and makes such programs
27 easier to port.
28 Organization of This Standard
29 The standard is divided into three parts:
30 — Statement of scope, list of normative references, and conformance information
31 (Section 1)
32 — Definitions and global concepts (Section 2)
33 — The various interface facilities (Sections 3 through 16)
34 The content of the sections parallels that of the correspondingly numbered sections of
35 the base standards (IEEE Std 1003.1-1990, as amended by IEEE Std 1003.1b-1993,
Introduction xi
1 IEEE Std 1003.1c-1995, and IEEE Std 1003.1i-1995), with some changes required to
2 fit the style of IEEE Std 1003.5-1993. There is no Section 10, since there is no Ada
3 binding for that section (Data Interchange Formats) of the base standards.
4 This introduction, any footnotes, notes accompanying the text, and the informative
5 annexes are not considered part of this standard.
6 Related Standards Activities
7 Activities to extend this standard to address additional requirements are in progress,
8 and similar efforts can be anticipated in the future.
9 The following areas are under active consideration at this time, or are expected to
10 become active in the near future:
11 (1) Language-independent descriptions of the services defined by IEEE-Std 1003.1-
12 1990 and its amendments.
13 (2) C and FORTRAN language bindings to (1)
14 (3) Shell and utility facilities
15 (4) Verification testing methods
16 (5) Secure/Trusted system considerations
17 (6) Network interface facilities
18 (7) System administration
19 (8) Graphical user interfaces
20 (9) Profiles describing application- or user-specific combinations of open systems
21 standards for: supercomputing, multiprocessor, and batch extensions; transac-
22 tion processing; realtime systems; and multiuser systems based on historical
23 models
24 (10) An overall guide to POSIX-based or related Open Systems standards and profiles
25 Extensions are approved as “amendments” or “revisions” to this standard, following
26 IEEE and ISO/IEC procedures.
27 Approved amendments are published separately until the full standard is reprinted
28 and such amendments are incorporated in their proper positions.
29 If you have an interest in participating in the PASC working groups addressing these
30 issues, please send your name, address, and phone number to the Secretary, IEEE
31 Standards Board, Institute of Electrical and Electronics Engineers, Inc., P.O. Box
32 1331, 445 Hoes Lane, Piscataway, NJ 08855-1331, USA, and ask to have this for-
33 warded to the chair of the appropriate PASC working group. If you have an interest
34 in participating in this work at the international level, contact your ISO/IEC national
35 body.
36 1
A Standards Status Report that lists all current IEEE Computer Society standards projects is
37 available from the IEEE Computer Society, 1730 Massachusetts Avenue NW, Washington, DC 20036-
38 1903, USA; Telephone: [phone]; FAX: [phone].
xii Introduction
1 IEEE Std 1003.5-1992 was prepared by the 1003.5 Working Group, sponsored by the
2 Technical Committee on Operating Systems and Applications Environments of the
3 IEEE Computer Society. At the time this standard was approved, the membership
4 of the IEEE P1003.5 working group was as follows:
5 Technical Committee on Operating Systems
6 and Application Environments (TCOS)
7 Chair: Jehan-Franc¸ois Parisˆ
8 TCOS Standards Subcommittee
9 Chair: Jim Isaak
10 Vice Chairs: Ralph Barker
11 Hal Jesperson
12 Lorraine Kevra
13 Pete Meier
14 Andrew Twigger
15 Treasurer: Peter Smith
16 Secretary: Shane McCarron
17 P1003.5 Working Group Officials
18 Chair: James P. Lonjers
19 Steven Deller (1989-1991)
20 Major Terrence Fong (1988-1989)
21 Vice Chairs: James P. Lonjers (1990-1991)
22 Major Terrence Fong (1989-1990)
23 Stowe Boyd (1988-1989)
24 Editors: David Emery
25 Hal Jesperson
26 Steven Deller (1988-1989)
27 Rationale Editor: Mitch Gart
28 Secretary: C. Jayne Baker
29 David Emery (1988-1989)
30 Technical Reviewers
31 Ted Baker David Emery Jim Lonjers
32 Steven Deller Mitch Gart Jim Moore
33 Dennis Doubleday Stephen Schwarm
34 Working Group
35 Ted Baker Michael Gillam Sue LeGrand
36 Stowe Boyd Al Globus James Lonjers
37 Bevin Brett Mars Gralia James Moore
38 Charles Brown Jayne Guyse Mark Ruddock
39 Robert Brown Ken Harvey Stephen Schwarm
40 Bhavesh Damania Ruth Hirt Michael Shapiro
41 Steven Deller Jeff Hooley Brian Sullivan
42 Dennis Doubleday Michael Kjolsrud Del Swanson
43 David Emery Peter Krupp Robert Voigt
44 Terry Fong James Leathrum Olle Wikstrom
45 Mitchell Gart John Zenor
Introduction xiii
1 The following persons were members of the 1003.5 balloting group that approved the
2 standard for submission to the IEEE Standards Board:
3 Harold C. Adams Andrew Chung Allen L. Grau
4 John S. Adams Brad Clark Charles R. Grauling
5 Omar Ahmed Lori A. Clarke Daniel Green
6 David Allen Norman H. Cohen Tom Griest
7 Charles J. Antonelli Edward Colbert F. Grize
8 B. Ardary Phillippe Collard Ernesto Guerrieri
9 David Athersych Robert A. Conti Lawrence
...