1EVAL(1P) POSIX Programmer's Manual EVAL(1P)
2
6 This manual page is part of the POSIX Programmer's Manual. The Linux
7 implementation of this interface may differ (consult the corresponding
8 Linux manual page for details of Linux behavior), or the interface may
9 not be implemented on Linux.
10
12 eval - construct command by concatenating arguments
13
15 eval [argument ...]
16
18 The eval utility shall construct a command by concatenating arguments
19 together, separating each with a <space>. The constructed command shall
20 be read and executed by the shell.
21
23 None.
24
26 See the DESCRIPTION.
27
29 Not used.
30
32 None.
33
35 None.
36
38 Default.
39
41 Not used.
42
44 The standard error shall be used only for diagnostic messages.
45
47 None.
48
50 None.
51
53 If there are no arguments, or only null arguments, eval shall return a
54 zero exit status; otherwise, it shall return the exit status of the
55 command defined by the string of concatenated arguments separated by
56 <space>s.
57
59 Default.
60 The following sections are informative.
62
64 None.
65
67 foo=10 x=foo
68 y='$'$x
69 echo $y
70 $foo
71 eval y='$'$x
72 echo $y
73 10
74
76 None.
77
79 None.
80
82 Special Built-In Utilities
83
85 Portions of this text are reprinted and reproduced in electronic form
86 from IEEE Std 1003.1, 2003 Edition, Standard for Information Technology
87 -- Portable Operating System Interface (POSIX), The Open Group Base
88 Specifications Issue 6, Copyright (C) 2001-2003 by the Institute of
89 Electrical and Electronics Engineers, Inc and The Open Group. In the
90 event of any discrepancy between this version and the original IEEE and
91 The Open Group Standard, the original IEEE and The Open Group Standard
92 is the referee document. The original Standard can be obtained online
93 at http://www.opengroup.org/unix/online.html .
94IEEE/The Open Group 2003 EVAL(1P)