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
12 unalias — remove alias definitions
13
15 unalias alias-name...
16 unalias -a
18
20 The unalias utility shall remove the definition for each alias name
21 specified. See Section 2.3.1, Alias Substitution. The aliases shall be
22 removed from the current shell execution environment; see Section 2.12,
23 Shell Execution Environment.
24
26 The unalias utility shall conform to the Base Definitions volume of
27 POSIX.1‐2017, Section 12.2, Utility Syntax Guidelines.
28 The following option shall be supported:
30 -a Remove all alias definitions from the current shell execution
32 environment.
33
35 The following operand shall be supported:
36 alias-name
38 The name of an alias to be removed.
39
41 Not used.
42
44 None.
45
47 The following environment variables shall affect the execution of una‐
48 lias:
49 LANG Provide a default value for the internationalization vari‐
51 ables that are unset or null. (See the Base Definitions vol‐
52 ume of POSIX.1‐2017, Section 8.2, Internationalization Vari‐
53 ables for the precedence of internationalization variables
54 used to determine the values of locale categories.)
55 LC_ALL If set to a non-empty string value, override the values of
57 all the other internationalization variables.
58 LC_CTYPE Determine the locale for the interpretation of sequences of
60 bytes of text data as characters (for example, single-byte as
61 opposed to multi-byte characters in arguments).
62 LC_MESSAGES
64 Determine the locale that should be used to affect the format
65 and contents of diagnostic messages written to standard
66 error.
67 NLSPATH Determine the location of message catalogs for the processing
69 of LC_MESSAGES.
70
72 Default.
73
75 Not used.
76
78 The standard error shall be used only for diagnostic messages.
79
81 None.
82
84 None.
85
87 The following exit values shall be returned:
88 0 Successful completion.
90 >0 One of the alias-name operands specified did not represent a
92 valid alias definition, or an error occurred.
93
95 Default.
96 The following sections are informative.
98
100 Since unalias affects the current shell execution environment, it is
101 generally provided as a shell regular built-in.
102
104 None.
105
107 The unalias description is based on that from historical KornShell
108 implementations. Known differences exist between that and the C shell.
109 The KornShell version was adopted to be consistent with all the other
110 KornShell features in this volume of POSIX.1‐2017, such as command line
111 editing.
112 The -a option is the equivalent of the unalias * form of the C shell
114 and is provided to address security concerns about unknown aliases
115 entering the environment of a user (or application) through the allow‐
116 able implementation-defined predefined alias route or as a result of an
117 ENV file. (Although unalias could be used to simplify the ``secure''
118 shell script shown in the command rationale, it does not obviate the
119 need to quote all command names. An initial call to unalias -a would
120 have to be quoted in case there was an alias for unalias.)
121
123 None.
124
126 Chapter 2, Shell Command Language, alias
127 The Base Definitions volume of POSIX.1‐2017, Chapter 8, Environment
129 Variables, Section 12.2, Utility Syntax Guidelines
130
132 Portions of this text are reprinted and reproduced in electronic form
133 from IEEE Std 1003.1-2017, Standard for Information Technology -- Por‐
134 table Operating System Interface (POSIX), The Open Group Base Specifi‐
135 cations Issue 7, 2018 Edition, Copyright (C) 2018 by the Institute of
136 Electrical and Electronics Engineers, Inc and The Open Group. In the
137 event of any discrepancy between this version and the original IEEE and
138 The Open Group Standard, the original IEEE and The Open Group Standard
139 is the referee document. The original Standard can be obtained online
140 at http://www.opengroup.org/unix/online.html .
141 Any typographical or formatting errors that appear in this page are
143 most likely to have been introduced during the conversion of the source
144 files to man page format. To report such errors, see https://www.ker‐
145 nel.org/doc/man-pages/reporting_bugs.html .
146IEEE/The Open Group 2017 UNALIAS(1P)