ISO/IEC 9945-2:1993

Information technology - Portable Operating System Interface (POSIX) - Part 2: Shell and Utilities

This part of ISO/IEC 9945 defines a standard source-code-level interface to command interpretation, or "shell," services and common utility programs for applica- tion programs. These services and programs are complementary to those specified by ISO/IEC 9945-1: 1990 (IEEE Std 1003.1-1990) {8}, hereinafter referred to as "POSIX.1 {8}." When the User Portability Utilities Option is included, this part of ISO/IEC 9945 has additional scope. The list of utilities and features is extended to provide a common interactive environment for system users and program developers. This part of ISO/IEC 9945 has been designed to be used by both application programmers and system implementors. When the User Portability Utilities Option is included, it is also to be used by system users and program developers. How- ever, it is intended to be a reference document and not a tutorial on the use of the services, the utilities, or the interrelationships between the utilities. The emphasis of this part of ISO/IEC 9945 without the User Portability Utilities Option is on the shell and utility functionality required by application programs (including "shell scripts") and not on the direct interactive use of the shell command language or the utilities by humans. When the User Portability Utilities Option is included, the emphasis is extended to support terminal users in a consistent manner across all conforming systems. There are three constraining factors that limit this user portability scope: (1) The users in this context are limited to the group of individuals who are familiar with the style of interaction characteristic of historically derived systems based on one of the UNIX operating systems. Typical users would include program developers, engineers, or general purpose time-sharing users. (2) The environment to be supported is a multi-user time-sharing system supporting character-oriented display terminals. Alternatively, it is a collection of single-user systems interconnected via local area networks or telephone lines, but with similar user interfaces. This part of ISO/IEC 9945 does not include support that is tailored for bit-mapped or graphics display terminals, although it is expected that such terminals could emu-late the character orientation required by this environment. When facili-ties require cursor addressability from the terminal hardware, this is specifically identified in this part ofISO/IEC 9945. (3) The facilities to be provided are based on the historical models of the fol- lowing documents: the System V Interface Definition {B37}, the BSD User Manual {B46}, the X/Open Portability Guide {B49}, and documentation for the KornShell {B38}. Emphasis is placed on standardizing existing practice for existing users, with changes or additions limited to correcting deficiencies in the following areas: (a) Support for international character sets and other localization requirements, such as date formats, collation sequences, etc. (b) Reconciliation of differences between the historical implementa­tions. (c) Elimination of system or device dependencies. (d) Corrections of features that could reduce system or user security/integrity. Portions of this part of ISO/IEC 9945 comprise optional language bindings to sys-tern service interfaces. (See, for example, the C-Language Bindings Option in Annex B.) This part of ISO/IEC 9945 is intended to describe language interfaces and utilities in sufficient detail so that an application developer can understand the required interfaces without access to the source code of existing implementations on which they may be based. Therefore, it does not attempt to describe the source programming language or internal design of the utilities; they should be , considered "black boxes" that exhibit the described functionality. For language interfaces, or functions, this part of ISO/IEC 9945 has been defined exclusively at the source-code level. The objective is that a conforming portable application sourc

Technologies de l'information — Interface pour la portabilité des systèmes (POSIX) — Partie 2: Enveloppe et services

General Information

• Status: Withdrawn
• Publication Date: 22-Dec-1993
• Withdrawal Date: 22-Dec-1993
• 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: 13-Dec-2002
• Completion Date: 30-Oct-2025

Relations

• Revised: ISO/IEC 9945-3:2002 - Information technology - Portable Operating System Interface (POSIX) - Part 3: Shell and Utilities
• Effective Date: 15-Apr-2008
• Revised: ISO/IEC 9945-1:2002 - Information technology - Portable Operating System Interface (POSIX) - Part 1: Base Definitions
• Effective Date: 15-Apr-2008
• Revised: ISO/IEC 9945-2:2002 - Information technology - Portable Operating System Interface (POSIX) - Part 2: System Interfaces
• Effective Date: 15-Apr-2008
• Revised: ISO/IEC 9945-4:2002 - Information technology - Portable Operating System Interface (POSIX) - Part 4: Rationale
• Effective Date: 15-Apr-2008

Standards Content (Sample)

I NTE R NAT I O N AL ISO/IEC
STANDARD
ANSIAEEE
Std 1003.2
First edition
1993-1 2-22
Information technology - Portable Operating
System Interface (POSIX) -
Part 2:
Shell and Utilities
Volume I
Technologies de l'information - Interface pour la portabilité des systèmes
lP0SlXl -
Partie 2: Enveloppe et services
Tome 1
Reference number
ISO/I EC 9945-2: 1993(E)
ANSIAEEE
Std 1003.2-1993
The Institute of Electrical and Electronics Engineers, Inc.
345 East 47th Street, New York, NY 10017-2394, USA
Copyright O 1993 by the
Institute of Electrical and Electronics Engineers, Inc.
All rights reserved. Published 1993
Printed in the United States ofAmerica
ISBN 1-55937-255-9
No part of this publication may be reproduced in any form,
in an electronic retrieval system or otherwise,
without the prior written permission ofthe publisher:
SHI 5628
December 22, 1993
International Standard ISO/IEC 9945-2: 1993
ANSUIEEE Std 1003.2-1992
(Includes ANSUIEEE Std 1003.2a-1992)
Information technology-
Portable Operating System Interface
(POSIX)-Part 2: Shell and Utilities
(Volume 1)
Sponsor
Technical Committee on Operating Systems and Application Environments
of the
IEEE Computer Society
Approved September 17,1992
IEEE Standards Board
Approved April 5, 1993
American National Standards Institute
Approved 1993 by the
International Organization for Standardization
and by the
International Electrotechnical Commission
Abstract: This standard is part of the POSM series of standards for applications
and user interfaces to open systems. It defines the applications interface to a shell
command language and a set of utility programs for complex data manipulation.
When the User Portability Utilities Option is included, the standard also defines a
common environment for general-purpose time-sharing users on character-oriented
display terminals .
Keywords: API, application portability, data processing, open systems, operating
system, portable application, POSIX, shell and utilities, user portability
Adopted as an International Standard by the
.\.l.’ International Organization for Standardization
IB
and by the
International Electrotechnical Commission
m
American National Standard
Published by
The Institute of Electrical and Electronics Engineers, Inc.

Foreword
IS0 (the International Organization for Standardization) and IEC (the International
Electrotechnical Commission) form the specialized system for worldwide standardiz-
ation. National bodies that are members of IS0 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. IS0 and IEC technical
committees collaborate in fields of mutual interest. Other international organizations,
governmental and non-govemmcntal, in liaison with IS0 and IEC, also take part in the
work.
In the field of information technology, IS0 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 9945-2: 1993 was prepared by Joint Technical
Committee ISO/IEC JTC 1, Information technology, subcommittee 22, Programming
languages, their environments and system sofiare interfaces.
ISO/IEC 9945 consists of the following parts, under the general title Information
technology - Portable Operating System Interface (POSIX):
- Part 1 : System application program inte face (API) [C language]
- Part 2: Shell and Utilities
- Part 3: System administration (under development)
Annexes A, B and C form an intcgral pan of this pan of ISODEC9945.
Annexes D, E, F, G and H are for information only.
International Organization for Standardizationflntemational Electrotechnical Commission
Case postale 56 * CH-1211 Genève 20 * Switzerland

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Contents
PAGE
Foreword ix
......................
X
Introduction .
xi
..........
Organization of This Part of ISO/IEC 9945
................... xii
Base Documents .
Xlll
Related Standards Activities .
Sectionl: General .
1.1 Scope .
1.2 Normative References .
1.3 Conformance .
1.4 Test Methods .
........ 9
Section 2: Terminology and General Requirements
.................. 9
2.1 Conventions
................... 13
2.2 Definitions
2.3 Built-In Utilities . 39
2.4 Character Set . 40
..................... 44
2.5 Locale
2.6 Environment Variables . 73
.................. 77
2.7 Required Files
............. 77
2.8 Regular Expression Notation
2.9 Dependencies on Other Standards . 92
2.10 Utility Conventions . 97
2.11 Utility Description Defaults . 101
2.12 File Format Notation . 108
............... 111
2.13 Configuration Values
2.14 Terminal Characteristics . 114
Section 3: Shell Command Language . 117
3.1 Shell Introduction . 117
3.2 Quoting . 117
3.3 Token Recognition . 119
3.4 Reserved Words . 121
3.5 Parameters and Variables . 122
3.6 Word Expansions . 125
3.7 Redirection . 130
3.8 Exit Status and Errors . 133
3.9 Shell Commands . 135
3.10 Shell Grammar . 143
3.11 Signals and Error Handling . 149
3.12 Shell Execution Environment . 149
3.13 Pattern Matching Notation . 150
..
3.14 Special Built-In Utilities .
3.14.1 break-Exit from for. while. or until loop . 153
3.14.2 colon - Null utility .
3.14.3 continue - Continue for, while. or until loop . . 153
3.14.4 dot - Execute commands in current environment . 154
3.14.5 eval - Construct command by concatenating
arguments .
3.14.6 exec - Execute commands and open, close, and/or copy file
descriptors .
3.14.7 exit - Cause the shell to exit . 155
3.14.8 export - Set export attribute for variables . 155
3.14.9 readonly - Set read-only attribute for variables . 155
3.14.10 return - Return from a function . 156
3.14.11 set - Sethnset options and positional parameters . . 156
3.14.12 shift - Shift positional parameters . 159
3.14.13 trap - Trap signals . 160
3.14.14 unset - Unset values and attributes of variables and
functions .
Section 4: Execution Environment Utilities .
4.1 awk . Pattern scanning and processing language .
4.2 basename . Return nondirectory portion of pathname .
4.3 bc -Arbitrary-precision arithmeticlanguage .
4.4 cat . Concatenate and print files .
4.5 cd . Change working directory .
4.6 chgrp . Change file group ownership .
4.7 chmod - Change file modes . .
4.8 chow . Change file ownership .
4.9 cksum . Write file checksums and sizes .
4.10 cmp . Compare two files .
4.11 comm - Select or reject lines common to two files . 225
4.12 command . Execute a simple command . . 228
4.13 cp . Copy files .
4.14 cut . Cut out selected fields of each line of a file .
4.15 date . Write the date and time .
4.16 dd . Convert and copy a file .
4.17 dif f . Compare two files . .
4.18 dirname . Return directory portion of pathname .
4.19 echo . Write arguments to standard output .
4.20 ed - Edit text .
4.21 env . Set environment for command invocation .
4.22 expr . Evaluate arguments as an expression .
4.23 false . Return false value .
4.24 find-Findfiles . .
4.25 fold . Fold lines .
4.26 getconf . Get configuration values .
4.27 getopts . Parse utility options . , .
4.28 grep . File pattern searcher .
4.29 head . Copy the first part of files . 299
4.30 id - Return user identity .
...
4.31 j oin . Relational database operator .
4.32 ki 11 . Terminate or signal processes .
4.33 In . Link files .
4.34 locale . Get locale-specific information .
4.35 localedef . Define locale environment .
4.36 logger . Log messages .
4.37 logname . Return the login name of the user .
4.38 lp . Send files to a printer .
4.39 Is . List directory contents .
4.40 mai lx . Process messages .
4.41 mkdir . Make directories .
4.42 mkf i f o . Make FIFO special files .
4.43 mv . Move files .
4.44 nohup . Invoke a utility immune to hangups .
4.45 od . Dump files in various formats .
4.46 pas te . Merge corresponding or subsequent lines of files .
4.47 pathchk . Check pathnames .
4.48 pax . Portable archive interchange .
4.49 pr . Print files .
4.50 printf . Write formatted output .
4.51 pwd . Return working directory name . 396
4.52 read . Read a line from standard input .
4.53 rm . Remove directory entries .
4.54 rmdir . Remove directories .
4.55 sed . Stream editor .
4.56 sh . Shell, the standard command language interpreter . 414
4.57 sleep . Suspend execution for an interval .
4.58 sort . Sort, merge, or sequence check text files
...... 431
s t ty . Set the options for a terminal
4.59 . 437
4.60 tail . Copy the last part of a file . 444
4.61 tee . Duplicate standard input .
4.62 test . Evaluate expression .
4.63 touch . Change file access and modification times . 453
4.64 tr . Translate characters .
4.65 true . Return true value .
4.66 t ty . Return the terminal name of the user . 464
4.67 mask-Get or set the filemodecreationmask . 466
4.68 uname . Return system name .
4.69 uniq . Report or filter out repeated lines in a file .
4.70 wait . Await process completion . 474
wc . Word, line, and bytekharacter count .
4.71
4.72 xargs . Construct argument list(s) and invoke utility .
Section 5: User Portability Utilities Option . 485
5.1 alias . Define or display aliases .
5.2 at . Execute commands at a later time .
5.3 batch . Execute commands when the system load permits . .
5.4 bg . Run jobs in the background .
5.5 crontab-Scheduleperiodicbackgroundwork .
5.6 csplit - Split files based on context .
iv
.............. 505
5.7 ctags . Create a tags file
............. 509
5.8 df . Report free disk space
............ 512
5.9 du . Estimate file space usage
5.10 ex . Text editor .
expand . Convert tabs to spaces . 542
5.11
f c . Process command history list . 545
5.12
f g . Run jobs in the foreground . 550
5.13
file . Determine file type . 552
5.14
jobs . Display status of jobs in the current session . 555
5.15
man . Display system documentation . 558
5.16
mesg . Permit or deny messages . 561
5.17
more-display files on a page-by-page basis . 563
5.18
........... 574
5.19 newgrp . Change to a new group
5.20 nice . Invoke a utility with an altered system scheduling
priority .
5.21 nm . Write the name list of an object file .
5.22 patch . Apply changes to files .
5.23 ps . Report process status . 589
5.24 renice . Set system scheduling priorities of running processes . 594
5.25 split . Split files into pieces .
5.26 strings . Find printable strings in files . 600
5.27 tabs . Set terminal tabs . 603
5.28 talk . Talk to another user . 606
5.29 time . Time a simple command . 609
5.30 tput . Change terminal characteristics . 612
5.31 unalias . Remove alias definitions .
5.32 unexpand . Convert spaces to tabs .
5.33 uudecode . Decode a binary file .
5.34 uuencode . Encode a binary file . 621
vi . Screen-oriented (visual) display editor . 624
5.35
5.36 who . Display who is on the system . 655
5.37 write . Write to another user . 657
Section 6: Software Development Utilities Option . 661
6.1 ar . Create and maintain library archives . 661
make . Maintain, update. and regenerate groups of programs . 666
6.2
6.3 strip - Remove unnecessary information from executable files . 679
........ 683
Section 7: Language-Independent System Services
........ 683
7.1 Shell Command Interface .
7.2 Access Environmentvariables . .
7.3 RE Matching . .
........ 684
7.4 Pattern Matching .
........ 684
7.5 Command Option Parsing .
........ 685
7.6 Generate Pathnames Matching a Pattern
........ 685
7.7 Perform Word Expansions .
7.8 Get POSIX Configurable Variables . . 685
7.9 Locale Control . . 686
... 687
Annex A (normative) C-Language Development Utilities Option
V
A.l c8 9 . Compile Standard C programs . .
A.2 lex . Generate programs for lexical tasks .
A.3 yacc . Yet another compiler compiler .
AnnexB (normative) C-LanguageBindings Option .
B.l C-Language Definitions .
B.2 C Numeric Limits .
B.3 C Binding for Shell Command Interface .
B.4 C Binding for Access Environmentvariables .
B.5 C Binding for RE Matching .
B.6 C Binding for Match Filename or Pathname .
B.7 C Binding for Command Option Parsing .
B.8 C Binding for Generate Pathnames Matching a Pattern .
B.9 C Binding for Perform Word Expansions .
B.10 C Binding for Get POSIX Configurable Variables . 739
B.ll C Binding for Locale Control . 741
Annex C (normative) FORTRAN Development and Runtime Utilities
Options .
C.1 asa-Interpret carriage-control characters .
C.2 fort77 -FORTRAN compiler .
Annex D (informative) Bibliography .
AnnexE (informative) Rationale and Notes . .
E.l General .
.... 755
E.2 TerminologyandGeneral Requirements .
....
E.3 Shell Command Language .
....
E.4 Execution Environment Utilities .
....
E.5 User Portability Utilities Option .
.... 971
E.6 Software Development Utilities Option .
.... 1011
E.7 Language-Independent Systemservices .
....
E.8 C-Language Development Utilities Option .
.... 1022
E.9 C-Language Bindings Option .
.... 1033
E.10 FORTRAN Development and Runtime Utilities Options
.... 1049
AnnexF (informative) Portability Considerations .
F.l User Requirements .
F.2 Portability Capabilities .
F.3 Profiling Considerations .
Annex G (informative) Sample National Profile . 1063
G.l Danish National Profile Example .
G.2 Additional Danish Utility Requirements .
G.3 Locale String Definition Guideline .
G.4 Scope of Danish National Locale . 1068
G.5 Character Mnemonics Guidelines .
G.6 Danish Charmap File Examples . 1152
AnnexH (informative) Proposals for Future Revisions .
vi
H.l Resolve International Comments toDIS 9945-2 . 1193
H.2 Resolve Interpretation Requests and Correct Technical Defects . 1196
H.3 Revise Granularity of Options . 1197
H.4 Support Features of 9945-1 Revision . 1197
H.5 Reorganize 9945-1 and 9945-2 Material . 1198
Identifier Index . 1199
Alphabetic Topical Index . 1203
FIGURES
. bc Exponential Example .
Figure E-1 874
. Shell Script Simulating cat s .
E-2
Figure 875
. ASCII to EBCDIC Conversion .
Figure E-3 895
. ASCII to IBM EBCDIC Conversion .
Figure E-4 896
. getopts Example .
Figure E-5 911
. nice Implementation Example .
Figure E-6 995
. lex Example Program .
Figure E-7 1029
. Sample system() Implementation .
Figure E-8
. Sample pcZose0 Implementation .
Figure E-9
. Example RE Matching . 1041
Figure E-10
. Argument Processing Withgetopt0 . . 1044
Figure E-11
TABLES
Typographical Conventions . 9
Table 2-1 .
Table 2-2 . Job Control Job ID Formats . 27
Regular Built-in Utilities . 39
Table 2-3 .
Character Set and Symbolic Names . 40
Table 2-4 .
Control Character Set . 42
Table 2-5 .
LC-CTYPE Category in the POSIX Locale .
Table 2-6 . 49
Table 2-7 . Valid Character Class Combinations . 52
LC-COLLATE Category in the POSIX Locale . 54
Table 2-8 .
Table 2-9 . LC-MONETARY Category in the POSIX Locale . 60
LC-NUMERIC Category in the POSIX Locale . 63
Table 2-10 .
LC-TIME Category in the POSIX Locale . 65
Table 2-11 .
LC-MESSAGES Category in the POSIX Locale . 67
Table 2-12 .
BRE Precedence . 83
Table 2-13 .
ERE Precedence . 87
Table 2-14 .
C Standard Operators and Functions . 96
Table 2-15 .
Escape Sequences . 109
Table 2-16 .
Table 2-17 . .
Utility Limit Minimum Values 112
Symbolic Utility Limits . 113
Table 2-18 .
Optional Facility Configuration Values . 114
Table 2-19 .
Control Character Names . 115
Table 2-20 .
vii
Table 3-1 . Shell Error Summary . 134
Table 4-1 . awk Expressions in Decreasing Precedence . 168
Table 4-2 . awk Escape Sequences . 188
Table 4-3 . bc Operators .
Table 4-4 . chmod Octal Mode Values .
Table 4-5 . expr Expressions .
Table 4-6 . od Named Characters . 373
Table 4-7 . s t ty Control Character Names . 441
Table 4-8 . stty Circumflex Control Characters . 442
Table 5-1 . file Output Strings . 554
Table 5-2 . ps Variable Names and Default Headers . 593
Table 7-1 . POSIX.1 Numeric-Valued Configurable Variables .
Table A-1 . lex Table Size Declarations .
Table A-2 . lex Escape Sequences . 699
Table A-3 . lex ERE Precedence .
Table A-4 . yacc Internal Limits . 717
Table B-1 . POSIX.2 Reserved Header Symbols . 720
Table B-2 . . POSIX-C-SOURCE .
Table B-3 . C Macros for Symbolic Limits .
Table B-4 . C Compile-Time Symbolic Constants . .
Table B-5 . C Execution-Time SymbolicConstants .
Table B-6 . Structure Type regex-t . 727
Table B-7 . Structure Type regmatch-t . 727
Table B-8 . regcomp ( ) cflags Argument . 727
Table B-9 . regexec ( ) eflags Argument . 727
Table B-10 . regcompo, regexeco Return Values .
Table B-11 . fnmatch0flags Argument .
Table B-12 . Structure Type glob-t .
Table B-13 . glob() flags Argument . 735
Table B-14 . glob() Error Return Values . 736
Table B-15 . Structure Type wordexp-t . 737
Table B-16 . wordexp () flags Argument .
Table B-17 . wordexp () Return Values .
Table B-18 . confstro name Values .
Table B-19 . C Bindings for Numeric-Valued Configurable Variables .
Table E-1 . Parameter Expansion Summary .
Table E-2 . dirname Examples . , .
Table E-3 . Optional Utility Combinations .
Table F-1 . POSIX.2 Portability Capability Summary .
Table G-1 . Danish Locale Options .
...
Vlll
Introduction
(This introduction is not a normative part of ISOAEC 9945-2, Information Technology - Portable
Operating System Interface (POSIX) - Part 2: Shell and Utilities, but is included for information
only.)
1 The primary purpose of this part of ISO/IEC 9945 is to define a standard interface
2 and environment for application programs that require the services of a “shell”
3 command language interpreter and a set of common utility programs. It is
4 intended for systems implementors and application software developers and is
5 complementary to ISODEC 9945-1: 1990 (IEEE Std 1003.1-1990) {SI1’ (first in a
6 family of “POSIX” standards), which specifies operating system interfaces and
7 source code level functions based on the UNIX2’ system documentation. This part
8 of ISO/IEC 9945, referred to as “POSIX.2,” is based upon documentation and the
9 knowledge of existing programs that assume an interface and architecture similar
10 to that described by POSM.1. (See 1.1 for a full description of the relationship
11 between the standards.)
12 The secondary purpose of this part of ISO/IEC 9945 is to supplement the applica-
13 tion portability interfaces to promote the “portability” of users and programmers
14 between conforming systems. The User Portability Utilities Option extends the
15 list of utilities, and features of utilities used primarily for application portability,
16 to provide a common interactive environment. It is intended for end users, pro-
17 gram developers, systems implementors, and application software developers.
18 Interfaces to satisfy these two purposes were originally developed by two separate
working groups, with user portability options packaged as a supplementary docu-
20 ment to the base set of application portability features. However, since the
21 development schedules eventually coincided, the draft documents have been
merged editorially into this single part of ISO/IEC 9945. Even with this merger,
the user portability features remain an optional component of this part of ISO/IEC
9945 *
25 The majority of this part of ISO/IEC 9945 describes the functions of utilities that
26 can interface with application programs. The standard also provides high-level
27 language interfaces that the application uses to access these utilities and other
28 useful, related services. These language-independent service interfaces are tem-
29 The C language
porarily described in terms of their C-language bindings.
assumed is that defined by the C Standard: ISO/IEC 9899: 1990 (7j.
31 1) The number in braces corresponds to those of the references in 1.2 (or the bibliographic entry in
32 Annex D if the number is preceded by the letter B).
33 2) UNIX is a registered trademark of UNE System Laboratories in the USA and other countries.
X Introduction
Organization of This Part of ISO/IEC 9945
35 This part of ISO/IEC 9945 is divided into ten parts:
36 - General, including a statement of scope, normative references, conformance
37 requirements, and test methods (Section 1).
38 - Definitions, general requirements, and the environment available to appli-
cations (Section 2).
40 - The shell command language (Section 3).
41 - Descriptions of the utilities in the required “Execution Environment Utili-
ties” (Section 4).
43 - Descriptions of the utilities in the optional “User Portability Utilities,” for
44 interactive users on asynchronous terminals (Section 5).
- Descriptions of the utilities in the optional “Software Development Utili-
ties” (Section 6).
47 - Language-independent interfaces for high-level programming language
48 access to shell and related services (Section 7).
49 - Descriptions of the utilities in the optional “C-Language Development Utili-
50 ties” (Annex A).
- C-language bindings to the interfaces in Section 7 (Annex B).
52 - Descriptions of the utilities in the optional “FORTRAN Development and
53 Runtime Utilities” (Annex C).
54 This introduction, the foreword, any footnotes, notes accompanying the text, and
55 the informative annexes are not considered part of this part of ISO/IEC 9945.
Annexes D through H are informative. The line numbers are also not part of the
standard. They were added as an aid to the user due to the size of the document,
but they can vary in, or be omitted from, other editions translated into languages
other than Engli~h.~)
60 3) Because of minor editorial differences, some line numbers, page breaks, and bibliographic
61 reference numbers of the POSIX.2 version printed in June 1993 differ slightly from those in this
version, the joint publication of IEEE Std 1003.2-1992 and ISO/IEC 9945-2: 1993 (E). There are
also informative differences in Annexes D, G, and H; however, there are no normative differences
64 between these two printings. To assist in citing passages from the standard precisely, such as
for interpretation requests, readers are urged to identify the printed version of the standard-
either the “IEEE-only version” or the “joint IEEE/ISO/IEC version”-along with line and page
67 numbers and appropriate subclause numbers.
xi
68 Base Documents
69 Many of the interfaces and utilities of this part of ISO/IEC 9945 were adapted
70 from materials in machine-readable forms donated by the following organizations:
71 - AT&T: the System V Interface Definition (SVID) {B37}, Issue 2, Volume 2.
72 Copyright O 1986, AT&T; reprinted with permission.
73 - The WOpen Company, Ltd.: the XIOpen Portability Guide Issues II {B48}
74 and III (B491, Volume 1. Copyright O 1989, WOpen Company, Ltd;
75 reprinted with permission.
- University of California, The UNIX User’s Reference Manual {B46}, 4.3
Berkeley Software Distribution, Virtual VAX-11 Version, 1986. Copyright
78 O 1980, 1983, The Regents of the University of California; reprinted with
79 permis~ion.~)
Significant reference use was also made of the following books:
81 - Bolsky, Morris I. and Korn, David G., The KornShell Command and Pro-
82 gramming Language IB38). Englewood Cliffs, New Jersey: Prentice Hall,
83 1988.
- Aho, Alfred V., Kernighan, Brian W., and Weinberger, Peter J., The AWK
Programming Language {B34}. Reading, Massachusetts: Addison-Wesley,
1988.
87 Many other proposals for functions and utilities were received from the various
88 working group members, who are listed later in this introduction.
4) The IEEE is grateful to AT&T, WOpen, and the Regents of the University of California for
90 permission to use their machine-readable materials.
xii Introduction
91 Related Standards Activities
92 Activities to extend this part of ISO/IEC 9945 to address additional requirements
are in progress, and similar efforts can be anticipated in the future.
94 The following areas are under active consideration at this time or are expected to
95 become active in the near future?
Language-independent service descriptions of POSIX. 1 IS}
97 C, Ada, and Fortran Language bindings to (1)
98 Verification testing methods
99 Realtime facilities
100 SecurePl’rusted System considerations
101 Network interface facilities
System Administration
103 Graphical User Interfaces
Profiles describing application- or user-specific combinations of Open Sys-
tems standards for: supercomputing, multiprocessor, and batch exten-
106 sions; transaction processing; realtime systems; and multiuser systems
107 based on historical models
108 An overall guide to POSIX-based or related Open Systems standards and
109 profiles
Extensions are approved as “amendments” or “revisions” to this document, follow-
ing the IEEE and ISOAEC Procedures.
112 Approved amendments are published separately until the full document is
reprinted and such amendments are incorporated in their proper positions.
114 If you have an interest in participating in the TCOS working groups addressing
115 these issues, please send your name, address, and phone number to the Secretary,
IEEE Standards Board, Institute of Electrical and Electronics Engineers, Inc.,
117 P.O. Box 1331, 445 Hoes Lane, Piscataway, NJ 08855-1331, USA, and ask. to have
118 this forwarded to the chair of the appropriate TCOS working group. If you have
an interest in participating in this work at the international level, contact your
120 ISOAEC national body.
~
5) A Standards Status Report that lists all current IEEE Computer Society standards projects is
available from the IEEE Computer Society, 1730 Massachusetts Avenue NW, Washington, DC
20036-1903, USA; Telephone: [phone]; FAX: [phone].
Related Standards Activities xiii

124 ISO/IEC 9945-2 was prepared by the P1003.2 working group, sponsored by the
of the
125 Technical Committee on Operating Systems and Application Environments
126 IEEE Computer Society. At the time this part of ISO/IEC 9945 was approved, the
127 membership of the P1003.2 working group was as follows:
Technical Committee on Operating Systems
and Application Environments (TCOS)
Chair: Jehan-François Pâris
131 TCOS Standards Subcommittee
Chair: Jim Isaak
Vice-Chairs: Ralph Barker
Hal Jespersen
Lorraine C. Kevra
Pete Meier
Andrew T. Twigger
Treasurer: Quin Hahn
Secretary: Shane P. McCarron
P1003.2 Working Group Officials
Chair: Hal Jespersen
Vice-Chair: Donald W. Cragun
Editors: Hal Jespersen (1986, 1988-1992)
Maggie Lee (1987-1988)
Secretaries: Lorraine C. Kevra (1987)
Robert J. Makowski (1988)
Helene Armitage (1988-1990)
Dave Grindeland (1991-1992)
P1003.2 Technical Reviewers
Gary W. Miller
Kenneth T. Faubel
150 Helene Armitage
Marc Teitelbaum
Greger Leijonhufvud
151 Keith Bostic
Robert M. Lenk Donn S. Terry
152 John Caywood
Teoman Topcubasi
Mark Levine
Donald W. Cragun
Shane McCarron David Willcox
David Decot
P1003.2a Technical Reviewers
Gary W. Miller
Helene Armitage Donald W. Cragun
Dave Grindeland Scott Sutter
Keith Bostic
Hal Jespersen
P1003.2 Working Group
Richard W. Elwood
James A. Capps
160 Helene Armitage
Hirsaki Eto
Bill Carpenter
161 Brian Baird
Fran Fadden
Steven L. Carter
162 John R. Barr
Kenneth T. Faubel
John Caywood
163 Philippe Bertrand
Martin C. Fong
Robert L. Claeson
164 Robert Bismuth
Glenn Fowler
Jim Blondeau Mark Colburn
Gary A. Gaudet
Donald Cragun
166 James C. Bohem
Al Gettier
Dave Decot
167 Kathy Bohrer
Timothy D. Gill
Terence S. Dowling
168 Keith Bostic
Gregory Goddard
Stephen A. Dum
169 Phyllis Eve Bregman
Loretta Goudie
Dominic Dunlop
170 Peter Brouwer
John Lawrence Gregg
Mike Edmonds
171 Jonathan Brown
Jerry Gross
Ron Elliott
172 Fred Lee Brown, Jr.
Introduction
xiv
173 Douglas A. Gwyn
Dan Magenheimer Norman K. Scherer
174 Quin Hahn
Shane McCarron Glen Seeds
175 Michael J. Hannah
Jim McGinness Jim Selkaitis
176 Marjorie E. Harris
John J. McGrory, Jr. Karen Sheaffer
177 David F. Hinnant
Stuart McKaig Del Shoemaker
178 Leon M. Holmes
Sunil Mehta James Soddy
179 Ron Holt
Bill Middlecamp Daniel Steinberg
180 Randall Howard
Gary Miller Scott A. Sutter
181 Steven A. James
James M. Moe Ravi Tavakley
182 Steve Jennings
Yasushi Nakahara Marc Teitelbaum
183 Hal Jespersen
Martha Nalebuff Donn S. Terry
184 Ronald S. Karr
Sonya D. Neufer Jack Thompson
185 Lorraine C. Kevra
Landon Curt Noll Teoman Topcubasi
186 Martin J. Kirk
Robin T. O’Neill Eugene Tsuno
187 Brad Kline
Jim Oldroyd Geraldine Vitovitch
188 Hiromichi Kogure
Mark Parenti Mike Wallace
189 David Korn
John Peace Alan G. Weaver
190 Rick Kuhn
Jon Penner Larry Wehr
191 Mike Lambert
Gerald Powell Bruce Weiner
192 Perry Lee
John S. Quarterman Nicholas Ray Wilkes
193 Greger Leijonhufvud
Joseph Ramus David Willcox
194 Robert M. Lenk
Mike Ressler Neil Winton
195 Mark Levine
Grover Righter Morten With
Gary Lindgren Andrew K. Roach Ken Witte
Car1 von Loewenfeldt
197 Marco P. Roodzant David Woodend
198 John Lomas Seth Rosenthal John Wu
199 Craig Lund Maude Sawyer Peggy Younger
200 Rod MacDonald Hilary Zaloom
20 1 P1003.2a Working Group
202 Helene Armitage
Hirsaki Eto Maggie Lee
203 Stephen R. Bartels
Kenneth T. Faubel Greger Leijonhufvud
204 Charles C. Bennett, Jr.
Glenn Fowler Robert M. Lenk
205 Philippe Bertrand Curtis Galloway Mark Levine
206 Ron Bird Gary A. Gaudet Dan Magenheimer
207 Robert Bismuth Al Gettier Robert J. Makowski
John Bissel1
208 Timothy D. Gill Shane P. McCarron
Jim Blondeau
209 Gregory Goddard John J. McGrory, Jr.
210 James C. Bohem Loretta Goudie Stuart McKaig
211 Kathy Bohrer Dave Grindeland T. Ted McMillan
212 Keith Bostic Jerry Gross
Sunil Mehta
213 Phyllis Eve Bregman Brian Hackworth
Francoise Miane
214 Peter Brouwer Michael J. Hannah
Bill Middlecamp
215 Jonathan Brown Marjorie E. Harris
Gary W. Miller
216 Fred Lee Brown, Jr. Hiroki Higuchi
Carlos E. Montero-Luque
217 Steven L. Carter David F. Hinnant
Yasushi Nakahara
218 Michael W. Cavins
Gai1 Holmes Martha Nalebuff
219 John Caywood
Ron Holt Paru1 S. Nanavati
220 Gerald Charlwood
Randall Howard Sonya D. Neufer
221 Mark Colburn
Akitaka Iwata Daniel Nissen
222 Donald W. Cragun
Hal Jespersen Landon Curt Noll
223 Claudia DeBlauu
Mike Karels Jim Oldroyd
224 Dave Decot
Ronald S. Karr John Peace
225 Mark Doran
Martin J. Kirk Per Pedersen
226 Stan Douglas
Will Kling Garth Perry
Edna Edelman
227 Hiromichi Kogure Pat Philip
Mike Edmonds
228 David Korn Rob Pike
229 Ron Elliott
Rick Kuhn John S. Quarterman
230 Richard W. Elwood
Mike Lambert Joseph Ramus
Related Standards Activities
xv
23 1 Mike Ressler Carolyn Surprenant Alan G. Weaver
232 Andrew K. Roach Scott A. Sutter Larry Wehr
233 Mark Roseman Ravi Tavakley Nicholas Ray Wilkes
234 Piyanai Saowarattitada Marc Teitelbaum David Willcox
235 Mike Schultz Donn S. Terry David Williams
236 Glen Seeds Teoman Topcubasi Neil Winton
Karen Sheaffer Eugene Tsuno Morten With
Harry Singh Yarko Tymcuerak John Wu
239 James Soddy Geraldine Vitovitch Jim Young
240 Mike Wallace
241 The following persons provided valuable input during the balloting period:
242 Scott Anderson Steven Howell Rob Peglar
243 Stephen Bartels Cheng Hu Rand S. Phares
244 Charles Bennet Andrew Hume Harold Rabbie
245 David R. Bernstein Richard James Chet Ramey
246 Karl Berry Bill Kalfakakos Brad Rhoades
247 Steve Bourne Chuck Karish Helmut Roth
248 Dawn Burnett Brian Kernighan David Rowley
249 David Butenhof Jim Kingdon Rob Sartin
250 Jeff Caldwell Wayne Krone Webb Scales
251 Randy Campbell Pat Kwan Roger Shimada
252 Andres Caravallo Mark E. Levine Keld Simonsen
Andy Cheese Maarten Litmaath John M. Sovereign
Robert Corbett David Long Bryan W. Sparks
C. Croes Paul Lustgarten
255 Henry Spencer
Paul J. Curtin Ron Mabe
256 Steven Spicer
257 Jeremy Epstein David J. MacKenzie Richard Stallman
Glenn Fowler Shane P. McCarron Peter Sugar
Brian Fox Roland McGrath Marc Teitelbaum
Janice Gee Doug McIlroy Trevor John Thompson
261 Jean Gilmore Anita Mundkur Daniel Tiernan
262 Lea Gottfredsen Yasushi Nakahara David Trueman
263 Dave Grindeland Shigekatsu Nakao Phong Vo
Jerry Gross Phi1 Nelson Milton B. Wagner
Mike Haertel Marc Nudelman Alex White
Kathy Hargreaves Alan F. Nugent Mike Wilson
267 Morris J. Herbert Ken O’Flaherty Hung P. Wong
268 Mark Horton Vern Paxson Jeff Wubik
269 The following persons were members of the 1003.2 balloting group that approved
270 the standard for submission to the IEEE Standards Board:
271 Peter Collinson USENIXAssociation Organizational Representative
272 Derek Kaufman XIOpen Organizational Representative
273 Shane P. McCarron UNIX International Organizational Representative
Helene Armitage Joseph Boykin
274 Mark Colburn
David Athersych Kevin Brady Kenneth N. Cole
Phyllis Eve Bregman Richard Cornelius
276 Geoff Baldwin
A. Winsor Brown William M. Convin
277 Jerome E. Banasik
Steven E. Barber F. Lee Brown, Jr. Mike R. Cossey
Luis-Felipe Cabrera William Cox
279 Robert M. Barned
Nicholas A. Camillone Donald W. Cragun
280 Kabekode V. S. Bhat
Robert Bismuth Steven L. Carter Dave Decot
282 Jim Blondeau John Caywood Terence Dowling
283 Robert Borochoff Kilnam Chon Stephen A. Dum
284 Keith Bostic Chan F. Chong John D. Earls
Ron Elliott
285 James P. Bound Robert L. Claeson
Introduction
286 Richard W. Elwood Robin B. Lake John S. Quarterman
287 David Emery Mike Lambert Wendy Rauch-Hindin
Philip H. Enslow Christopher J. Riddick
288 Doris Lebovits
Kenneth T. Faubel Maggie Lee Andrew K. Roach
Terence Fong Arnold Robbins
290 Greger Leijonhufvud
Ed Frankenbeny Robert M. Lenk Robert Sarr
Norman Schneidewind
292 John A. Gertwagen David Lennert
Wolfgang Schwabl
293 Al Gettier Kevin Lewis
Kin Fun Li Richard Scott
294 Michel Gien
Gregory W. Goddard James P. Lonjers Glen Seeds
Judy Guist Joseph F. P. Luhukay Dan Shia
Gregory Guthrie Heinz Lycklama Mukesh Singhal
Michael J. Hannah Robert J. Makowski Richard Sniderman
Steven Sommars
299 Carol J. Harkness Roger J. Martin
Joberto S. B. Martins Daniel Steinberg
300 Craig Harmer
Dale Harris Yoshihiro Matsumoto Douglas H. Steves
Myron Hecht Martin J. McGowan III Scott A. Sutter
David F. Hinnant Marshall Kirk McKusick Ravi Tavakley
Robert W. McWhirter Marc Teitelbaum
304 Lee A. Hollaar
Ronald Holt, Jr. Doug Michels Donn S. Terry
Randall Howard Gary W. Miller Gary F. Tom
Richard Hughes-Rowlands James M. Moe Teoman Topcubasi
Jim Isaak James W. Moore Andrew T. Twigger
Richard E. James Anita Mundkur Mark-Rene Uchida
310 Hal Jespersen Martha Nalebuff L. David Umbaugh
Michael W. Vannier
311 Greg Jones Landon Curt Nol1
John W. Walz
312 Michael J. Karels Fred Noz
Allan F. Nugent Alan G. Weaver
313 Lorraine C. Kevra
Larry A. Wehr
314 Alan W. Kiecker Jim R. Oldroyd
Craig Partridge Bruce Weiner
315 Jefiey S. Kimmel
Brian Weis
3 16 Martin J. Kirk John C. Penney
Peter J. Weyman
317 Kenneth C. Klingman P. J. Plauger
Andrew E. Wheeler, Jr.
318 Joshua W. Knight Gerald Powell
Scott E. Preece David Willcox
319 David Korn
Richard D. Kuhn James M. Purtilo Oren Yuen
Jason Zions
321 Takahiko Kuki
322 The following persons were members of the 1003.2a balloting group that approved
323 the standard for submission to the IEEE Standards Board:
Richard Alexander SHARE Organizational Representative
325 Ralph Barker UniForum Organizational Representative
326 Peter Collinson USENIX Association Organizational Representative
Derek Kaufman XlOpen Organizational Representative
James Bohem Kilnam Chon
328 Gary M. Allen
Helene Armitage Kathryn Bohrer Robert L. Claeson
Charles R. Arnold Keith Bostic William M. Convin
331 David Athersych Sven Brehmer Mike R. Cossey
332 Randall Atkinson David Brower William Cox
333 Ted P. Baker Gretchen Brown Donald W. Cragun
334 Timothy Baker John Carmichael Ana Maria DeAlvaré
335 Ralph Barker Steven L. Carter Virgil Decker
336 John Barr Jeny Cashin Steven Deller
331 Andy Bihain John Caywood Terence Dowling
338 Robert Bismuth Siddhartha Chattejee Stephen A. Dum
339 Nawaf Bitar Andy Cheese John D. Earls
340 George Bittner Janice Chelini Edna B. Edelman
Related Standards Activities xvii

341 Philip H. Enslow
Raymond A. Knighten Seth Rosenthal
342 Kester Fong
Ronnie Kon Piyanai Saowarattitada
Sheila Frankel
343 Richard D. Kuhn John Sauter
James Gibson
344 Robin B. Lake Richard Schaaf
345 Michel Gien Mike Lambert Lorne H. Schachter
346 Tom Griest Doris Lebovits Car1 Schmiedekamp
347 Dave Grindeland Maggie Lee Richard Scott
348 Robert C. Groman Robert M. Lenk Leonard Seagren
349 Judy Guist David Lennert
...