mirror of https://github.com/mkerrisk/man-pages
92 lines
1.9 KiB
Groff
92 lines
1.9 KiB
Groff
.\" Copyright (c) 2001-2003 The Open Group, All Rights Reserved
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.TH "TRUE" 1P 2003 "IEEE/The Open Group" "POSIX Programmer's Manual"
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.\" true
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.SH NAME
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true \- return true value
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.SH SYNOPSIS
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.LP
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\fBtrue\fP
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.SH DESCRIPTION
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.LP
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The \fItrue\fP utility shall return with exit code zero.
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.SH OPTIONS
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.LP
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None.
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.SH OPERANDS
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.LP
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None.
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.SH STDIN
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.LP
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Not used.
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.SH INPUT FILES
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.LP
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None.
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.SH ENVIRONMENT VARIABLES
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.LP
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None.
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.SH ASYNCHRONOUS EVENTS
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.LP
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Default.
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.SH STDOUT
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.LP
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Not used.
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.SH STDERR
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.LP
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Not used.
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.SH OUTPUT FILES
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.LP
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None.
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.SH EXTENDED DESCRIPTION
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.LP
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None.
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.SH EXIT STATUS
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.LP
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Zero.
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.SH CONSEQUENCES OF ERRORS
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.LP
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None.
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.LP
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\fIThe following sections are informative.\fP
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.SH APPLICATION USAGE
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.LP
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This utility is typically used in shell scripts, as shown in the EXAMPLES
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section. The special built-in utility \fB:\fP is
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sometimes more efficient than \fItrue\fP.
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.SH EXAMPLES
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.LP
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This command is executed forever:
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.sp
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.RS
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.nf
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\fBwhile true
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do
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command
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done
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\fP
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.fi
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.RE
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.SH RATIONALE
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.LP
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The \fItrue\fP utility has been retained in this volume of IEEE\ Std\ 1003.1-2001,
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even though the shell special
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built-in \fB:\fP provides similar functionality, because \fItrue\fP
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is widely used in historical scripts and is less cryptic to
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novice script readers.
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.SH FUTURE DIRECTIONS
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.LP
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None.
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.SH SEE ALSO
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.LP
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\fIfalse\fP , \fIShell Commands\fP
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.SH COPYRIGHT
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Portions of this text are reprinted and reproduced in electronic form
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from IEEE Std 1003.1, 2003 Edition, Standard for Information Technology
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-- Portable Operating System Interface (POSIX), The Open Group Base
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Specifications Issue 6, Copyright (C) 2001-2003 by the Institute of
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Electrical and Electronics Engineers, Inc and The Open Group. In the
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event of any discrepancy between this version and the original IEEE and
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The Open Group Standard, the original IEEE and The Open Group Standard
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is the referee document. The original Standard can be obtained online at
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http://www.opengroup.org/unix/online.html .
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