mirror of https://github.com/mkerrisk/man-pages
91 lines
2.0 KiB
Groff
91 lines
2.0 KiB
Groff
.\" Copyright (c) 2001-2003 The Open Group, All Rights Reserved
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.TH "EVAL" P 2003 "IEEE/The Open Group" "POSIX Programmer's Manual"
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.\" eval
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.SH NAME
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eval \- construct command by concatenating arguments
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.SH SYNOPSIS
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.LP
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\fBeval\fP \fB[\fP\fIargument\fP \fB...\fP\fB]\fP
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.SH DESCRIPTION
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.LP
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The \fIeval\fP utility shall construct a command by concatenating
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\fIargument\fPs together, separating each with a
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<space>. The constructed command shall be read and executed by the
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shell.
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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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See the DESCRIPTION.
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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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The standard error shall be used only for diagnostic messages.
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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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If there are no \fIargument\fPs, or only null arguments, \fIeval\fP
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shall return a zero exit status; otherwise, it shall
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return the exit status of the command defined by the string of concatenated
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\fIargument\fPs separated by <space>s.
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.SH CONSEQUENCES OF ERRORS
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.LP
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Default.
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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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None.
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.SH EXAMPLES
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.sp
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.RS
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.nf
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\fBfoo=10 x=foo
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y='$'$x
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echo $y
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\fP\fB$foo\fP\fBeval y='$'$x
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echo $y
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\fP\fB10\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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None.
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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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\fISpecial Built-In Utilities\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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