1UNALIAS(1P) POSIX Programmer's Manual UNALIAS(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
13 unalias — remove alias definitions
14
16 unalias alias-name...
17 unalias −a
19
21 The unalias utility shall remove the definition for each alias name
22 specified. See Section 2.3.1, Alias Substitution. The aliases shall be
23 removed from the current shell execution environment; see Section 2.12,
24 Shell Execution Environment.
25
27 The unalias utility shall conform to the Base Definitions volume of
28 POSIX.1‐2008, Section 12.2, Utility Syntax Guidelines.
29 The following option shall be supported:
31 −a Remove all alias definitions from the current shell execution
33 environment.
34
36 The following operand shall be supported:
37 alias-name
39 The name of an alias to be removed.
40
42 Not used.
43
45 None.
46
48 The following environment variables shall affect the execution of una‐
49 lias:
50 LANG Provide a default value for the internationalization vari‐
52 ables that are unset or null. (See the Base Definitions vol‐
53 ume of POSIX.1‐2008, Section 8.2, Internationalization Vari‐
54 ables for the precedence of internationalization variables
55 used to determine the values of locale categories.)
56 LC_ALL If set to a non-empty string value, override the values of
58 all the other internationalization variables.
59 LC_CTYPE Determine the locale for the interpretation of sequences of
61 bytes of text data as characters (for example, single-byte as
62 opposed to multi-byte characters in arguments).
63 LC_MESSAGES
65 Determine the locale that should be used to affect the format
66 and contents of diagnostic messages written to standard
67 error.
68 NLSPATH Determine the location of message catalogs for the processing
70 of LC_MESSAGES.
71
73 Default.
74
76 Not used.
77
79 The standard error shall be used only for diagnostic messages.
80
82 None.
83
85 None.
86
88 The following exit values shall be returned:
89 0 Successful completion.
91 >0 One of the alias-name operands specified did not represent a
93 valid alias definition, or an error occurred.
94
96 Default.
97 The following sections are informative.
99
101 Since unalias affects the current shell execution environment, it is
102 generally provided as a shell regular built-in.
103
105 None.
106
108 The unalias description is based on that from historical KornShell
109 implementations. Known differences exist between that and the C shell.
110 The KornShell version was adopted to be consistent with all the other
111 KornShell features in this volume of POSIX.1‐2008, such as command line
112 editing.
113 The −a option is the equivalent of the unalias * form of the C shell
115 and is provided to address security concerns about unknown aliases
116 entering the environment of a user (or application) through the allow‐
117 able implementation-defined predefined alias route or as a result of an
118 ENV file. (Although unalias could be used to simplify the ``secure''
119 shell script shown in the command rationale, it does not obviate the
120 need to quote all command names. An initial call to unalias −a would
121 have to be quoted in case there was an alias for unalias.)
122
124 None.
125
127 Chapter 2, Shell Command Language, alias
128 The Base Definitions volume of POSIX.1‐2008, Chapter 8, Environment
130 Variables, Section 12.2, Utility Syntax Guidelines
131
133 Portions of this text are reprinted and reproduced in electronic form
134 from IEEE Std 1003.1, 2013 Edition, Standard for Information Technology
135 -- Portable Operating System Interface (POSIX), The Open Group Base
136 Specifications Issue 7, Copyright (C) 2013 by the Institute of Electri‐
137 cal and Electronics Engineers, Inc and The Open Group. (This is
138 POSIX.1-2008 with the 2013 Technical Corrigendum 1 applied.) In the
139 event of any discrepancy between this version and the original IEEE and
140 The Open Group Standard, the original IEEE and The Open Group Standard
141 is the referee document. The original Standard can be obtained online
142 at http://www.unix.org/online.html .
143 Any typographical or formatting errors that appear in this page are
145 most likely to have been introduced during the conversion of the source
146 files to man page format. To report such errors, see https://www.ker‐
147 nel.org/doc/man-pages/reporting_bugs.html .
148IEEE/The Open Group 2013 UNALIAS(1P)