293 lines
8.2 KiB
Perl
293 lines
8.2 KiB
Perl
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.\" Copyright (c) 1983, 1993
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.\" The Regents of the University of California. All rights reserved.
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.\"
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.\" Redistribution and use in source and binary forms, with or without
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.\" modification, are permitted provided that the following conditions
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.\" are met:
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.\" 1. Redistributions of source code must retain the above copyright
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.\" notice, this list of conditions and the following disclaimer.
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.\" 2. Redistributions in binary form must reproduce the above copyright
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.\" notice, this list of conditions and the following disclaimer in the
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.\" documentation and/or other materials provided with the distribution.
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.\" 3. All advertising materials mentioning features or use of this software
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.\" must display the following acknowledgement:
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.\" This product includes software developed by the University of
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.\" California, Berkeley and its contributors.
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.\" 4. Neither the name of the University nor the names of its contributors
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.\" may be used to endorse or promote products derived from this software
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.\" without specific prior written permission.
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.\"
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.\" THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
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.\" ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
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.\" IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
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.\" ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
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.\" FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
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.\" DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
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.\" OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
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.\" HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
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.\" LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
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.\" OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
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.\" SUCH DAMAGE.
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.\"
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.\" @(#)0.t 8.1 (Berkeley) 6/8/93
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.\"
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.if n .ND
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.TL
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Berkeley Software Architecture Manual
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.br
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4.4BSD Edition
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.AU
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William Joy, Robert Fabry,
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.AU
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Samuel Leffler, M. Kirk McKusick,
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.AU
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Michael Karels
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.AI
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Computer Systems Research Group
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Computer Science Division
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Department of Electrical Engineering and Computer Science
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University of California, Berkeley
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Berkeley, CA 94720
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.EH 'PSD:5-%''4.4BSD Architecture Manual'
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.OH '4.4BSD Architecture Manual''PSD:5-%'
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.AB
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.FS
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* UNIX is a trademark of Bell Laboratories.
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.FE
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This document summarizes the facilities
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provided by the 4.4BSD version of the UNIX\|* operating system.
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It does not attempt to act as a tutorial for use of the system
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nor does it attempt to explain or justify the design of the
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system facilities.
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It gives neither motivation nor implementation details,
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in favor of brevity.
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.PP
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The first section describes the basic kernel functions
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provided to a UNIX process: process naming and protection,
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memory management, software interrupts,
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object references (descriptors), time and statistics functions,
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and resource controls.
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These facilities, as well as facilities for
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bootstrap, shutdown and process accounting,
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are provided solely by the kernel.
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.PP
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The second section describes the standard system
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abstractions for
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files and file systems,
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communication,
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terminal handling,
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and process control and debugging.
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These facilities are implemented by the operating system or by
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network server processes.
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.AE
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.LP
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.bp
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.ft B
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.br
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.sv 2
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.ce
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TABLE OF CONTENTS
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.ft R
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.LP
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.sp 1
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.nf
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.B "Introduction."
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.LP
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.if t .sp .5v
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.nf
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.B "0. Notation and types"
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.LP
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.if t .sp .5v
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.nf
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.B "1. Kernel primitives"
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.LP
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.if t .sp .5v
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.nf
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.nf
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\fB1.1. Processes and protection\fP
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1.1.1. Host and process identifiers
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1.1.2. Process creation and termination
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1.1.3. User and group ids
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1.1.4. Process groups
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.LP
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.nf
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\fB1.2. Memory management\fP
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1.2.1. Text, data and stack
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1.2.2. Mapping pages
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1.2.3. Page protection control
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1.2.4. Giving and getting advice
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1.2.5. Protection primitives
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.LP
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.if t .sp .5v
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.nf
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\fB1.3. Signals\fP
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1.3.1. Overview
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1.3.2. Signal types
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1.3.3. Signal handlers
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1.3.4. Sending signals
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1.3.5. Protecting critical sections
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1.3.6. Signal stacks
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.LP
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.if t .sp .5v
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.nf
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\fB1.4. Timing and statistics\fP
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1.4.1. Real time
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1.4.2. Interval time
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.LP
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.if t .sp .5v
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.nf
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\fB1.5. Descriptors\fP
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1.5.1. The reference table
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1.5.2. Descriptor properties
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1.5.3. Managing descriptor references
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1.5.4. Multiplexing requests
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1.5.5. Descriptor wrapping
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.LP
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.if t .sp .5v
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.nf
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\fB1.6. Resource controls\fP
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1.6.1. Process priorities
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1.6.2. Resource utilization
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1.6.3. Resource limits
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.LP
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.if t .sp .5v
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.nf
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\fB1.7. System operation support\fP
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1.7.1. Bootstrap operations
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1.7.2. Shutdown operations
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1.7.3. Accounting
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.bp
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.LP
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.if t .sp .5v
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.sp 1
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.nf
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\fB2. System facilities\fP
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.LP
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.if t .sp .5v
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.nf
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\fB2.1. Generic operations\fP
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2.1.1. Read and write
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2.1.2. Input/output control
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2.1.3. Non-blocking and asynchronous operations
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.LP
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.if t .sp .5v
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.nf
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\fB2.2. File system\fP
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2.2.1 Overview
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2.2.2. Naming
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2.2.3. Creation and removal
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2.2.3.1. Directory creation and removal
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2.2.3.2. File creation
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2.2.3.3. Creating references to devices
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2.2.3.4. Portal creation
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2.2.3.6. File, device, and portal removal
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2.2.4. Reading and modifying file attributes
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2.2.5. Links and renaming
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2.2.6. Extension and truncation
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2.2.7. Checking accessibility
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2.2.8. Locking
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2.2.9. Disc quotas
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.LP
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.if t .sp .5v
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.nf
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\fB2.3. Interprocess communication\fP
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2.3.1. Interprocess communication primitives
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2.3.1.1.\0 Communication domains
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2.3.1.2.\0 Socket types and protocols
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2.3.1.3.\0 Socket creation, naming and service establishment
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2.3.1.4.\0 Accepting connections
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2.3.1.5.\0 Making connections
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2.3.1.6.\0 Sending and receiving data
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2.3.1.7.\0 Scatter/gather and exchanging access rights
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2.3.1.8.\0 Using read and write with sockets
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2.3.1.9.\0 Shutting down halves of full-duplex connections
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2.3.1.10.\0 Socket and protocol options
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2.3.2. UNIX domain
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2.3.2.1. Types of sockets
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2.3.2.2. Naming
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2.3.2.3. Access rights transmission
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2.3.3. INTERNET domain
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2.3.3.1. Socket types and protocols
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2.3.3.2. Socket naming
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2.3.3.3. Access rights transmission
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2.3.3.4. Raw access
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.LP
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.if t .sp .5v
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.nf
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\fB2.4. Terminals and devices\fP
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2.4.1. Terminals
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2.4.1.1. Terminal input
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2.4.1.1.1 Input modes
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2.4.1.1.2 Interrupt characters
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2.4.1.1.3 Line editing
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2.4.1.2. Terminal output
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2.4.1.3. Terminal control operations
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2.4.1.4. Terminal hardware support
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2.4.2. Structured devices
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2.4.3. Unstructured devices
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.LP
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.if t .sp .5v
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.nf
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\fB2.5. Process control and debugging\fP
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.LP
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.if t .sp .5v
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.nf
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\fBI. Summary of facilities\fP
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.LP
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.de sh
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.ds RH \\$1
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.bp
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.NH \\*(ss
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\s+2\\$1\s0
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.PP
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.PP
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..
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.bp
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.ds ss 1
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.de _d
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.if t .ta .6i 2.1i 2.6i
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.\" 2.94 went to 2.6, 3.64 to 3.30
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.if n .ta .84i 2.6i 3.30i
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..
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.de _f
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.if t .ta .5i 1.25i 2.5i 3.5i
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.\" 3.5i went to 3.8i
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.if n .ta .7i 1.75i 3.8i 4.8i
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..
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.nr H1 -1
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.sh "Notation and types
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.PP
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The notation used to describe system calls is a variant of a
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C language call, consisting of a prototype call followed by
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declaration of parameters and results.
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An additional keyword \fBresult\fP, not part of the normal C language,
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is used to indicate which of the declared entities receive results.
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As an example, consider the \fIread\fP call, as described in
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section 2.1:
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.DS
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cc = read(fd, buf, nbytes);
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result int cc; int fd; result char *buf; int nbytes;
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.DE
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The first line shows how the \fIread\fP routine is called, with
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three parameters.
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As shown on the second line \fIcc\fP is an integer and \fIread\fP also
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returns information in the parameter \fIbuf\fP.
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.PP
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Description of all error conditions arising from each system call
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is not provided here; they appear in the programmer's manual.
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In particular, when accessed from the C language,
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many calls return a characteristic \-1 value
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when an error occurs, returning the error code in the global variable
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\fIerrno\fP.
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Other languages may present errors in different ways.
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.PP
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A number of system standard types are defined in the include file
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.I <sys/types.h>
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and used in the specifications here and in many C programs.
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These include \fBcaddr_t\fP giving a memory address (typically as
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a character pointer),
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\fBoff_t\fP giving a file offset (typically as a long integer),
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and a set of unsigned types \fBu_char\fP, \fBu_short\fP, \fBu_int\fP
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and \fBu_long\fP, shorthand names for \fBunsigned char\fP, \fBunsigned
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short\fP, etc.
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