1EXPORT(P) POSIX Programmer's Manual EXPORT(P)
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6 export - set the export attribute for variables
7
9 export name[=word]...
10 export -p
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15 The shell shall give the export attribute to the variables correspond‐
16 ing to the specified names, which shall cause them to be in the envi‐
17 ronment of subsequently executed commands. If the name of a variable is
18 followed by = word, then the value of that variable shall be set to
19 word.
20 The export special built-in shall support the Base Definitions volume
22 of IEEE Std 1003.1-2001, Section 12.2, Utility Syntax Guidelines.
23 When -p is specified, export shall write to the standard output the
25 names and values of all exported variables, in the following format:
26 "export %s=%s\n", <name>, <value>
29 if name is set, and:
31 "export %s\n", <name>
34 if name is unset.
36 The shell shall format the output, including the proper use of quoting,
38 so that it is suitable for reinput to the shell as commands that
39 achieve the same exporting results, except:
40 1. Read-only variables with values cannot be reset.
42 2. Variables that were unset at the time they were output need not be
44 reset to the unset state if a value is assigned to the variable
45 between the time the state was saved and the time at which the
46 saved output is reinput to the shell.
47 When no arguments are given, the results are unspecified.
49
51 See the DESCRIPTION.
52
54 See the DESCRIPTION.
55
57 Not used.
58
60 None.
61
63 None.
64
66 Default.
67
69 See the DESCRIPTION.
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72 The standard error shall be used only for diagnostic messages.
73
75 None.
76
78 None.
79
81 Zero.
82
84 Default.
85 The following sections are informative.
87
89 None.
90
92 Export PWD and HOME variables:
93 export PWD HOME
96 Set and export the PATH variable:
98 export PATH=/local/bin:$PATH
101 Save and restore all exported variables:
103 export -p > temp-fileunset a lot of variables... processing. temp-file
106
108 Some historical shells use the no-argument case as the functional
109 equivalent of what is required here with -p. This feature was left
110 unspecified because it is not historical practice in all shells, and
111 some scripts may rely on the now-unspecified results on their implemen‐
112 tations. Attempts to specify the -p output as the default case were
113 unsuccessful in achieving consensus. The -p option was added to allow
114 portable access to the values that can be saved and then later restored
115 using; for example, a dot script.
116
118 None.
119
121 Special Built-In Utilities
122
124 Portions of this text are reprinted and reproduced in electronic form
125 from IEEE Std 1003.1, 2003 Edition, Standard for Information Technology
126 -- Portable Operating System Interface (POSIX), The Open Group Base
127 Specifications Issue 6, Copyright (C) 2001-2003 by the Institute of
128 Electrical and Electronics Engineers, Inc and The Open Group. In the
129 event of any discrepancy between this version and the original IEEE and
130 The Open Group Standard, the original IEEE and The Open Group Standard
131 is the referee document. The original Standard can be obtained online
132 at http://www.opengroup.org/unix/online.html .
133IEEE/The Open Group 2003 EXPORT(P)