UNALIAS(1)                 POSIX Programmer's Manual                UNALIAS(1)



PPRROOLLOOGG
       This manual page is part of the POSIX Programmer's Manual.  The OS
       implementation of this interface may differ (consult the corresponding
       OS manual page for details of OS behavior), or the interface may not be
       implemented on OS.

NNAAMMEE
       unalias -- remove alias definitions

SSYYNNOOPPSSIISS
       unalias _a_l_i_a_s_-_n_a_m_e...

       unalias -a

DDEESSCCRRIIPPTTIIOONN
       The _u_n_a_l_i_a_s utility shall remove the definition for each alias name
       specified. See _S_e_c_t_i_o_n _2_._3_._1, _A_l_i_a_s _S_u_b_s_t_i_t_u_t_i_o_n.  The aliases shall be
       removed from the current shell execution environment; see _S_e_c_t_i_o_n _2_._1_2,
       _S_h_e_l_l _E_x_e_c_u_t_i_o_n _E_n_v_i_r_o_n_m_e_n_t.

OOPPTTIIOONNSS
       The _u_n_a_l_i_a_s utility shall conform to the Base Definitions volume of
       POSIX.1-2017, _S_e_c_t_i_o_n _1_2_._2, _U_t_i_l_i_t_y _S_y_n_t_a_x _G_u_i_d_e_l_i_n_e_s.

       The following option shall be supported:

       --aa        Remove all alias definitions from the current shell execution
                 environment.

OOPPEERRAANNDDSS
       The following operand shall be supported:

       _a_l_i_a_s_-_n_a_m_e
                 The name of an alias to be removed.

SSTTDDIINN
       Not used.

IINNPPUUTT FFIILLEESS
       None.

EENNVVIIRROONNMMEENNTT VVAARRIIAABBLLEESS
       The following environment variables shall affect the execution of
       _u_n_a_l_i_a_s:

       _L_A_N_G      Provide a default value for the internationalization
                 variables that are unset or null. (See the Base Definitions
                 volume of POSIX.1-2017, _S_e_c_t_i_o_n _8_._2, _I_n_t_e_r_n_a_t_i_o_n_a_l_i_z_a_t_i_o_n
                 _V_a_r_i_a_b_l_e_s for the precedence of internationalization
                 variables used to determine the values of locale categories.)

       _L_C___A_L_L    If set to a non-empty string value, override the values of
                 all the other internationalization variables.

       _L_C___C_T_Y_P_E  Determine the locale for the interpretation of sequences of
                 bytes of text data as characters (for example, single-byte as
                 opposed to multi-byte characters in arguments).

       _L_C___M_E_S_S_A_G_E_S
                 Determine the locale that should be used to affect the format
                 and contents of diagnostic messages written to standard
                 error.

       _N_L_S_P_A_T_H   Determine the location of message catalogs for the processing
                 of _L_C___M_E_S_S_A_G_E_S.

AASSYYNNCCHHRROONNOOUUSS EEVVEENNTTSS
       Default.

SSTTDDOOUUTT
       Not used.

SSTTDDEERRRR
       The standard error shall be used only for diagnostic messages.

OOUUTTPPUUTT FFIILLEESS
       None.

EEXXTTEENNDDEEDD DDEESSCCRRIIPPTTIIOONN
       None.

EEXXIITT SSTTAATTUUSS
       The following exit values shall be returned:

        0    Successful completion.

       >0    One of the _a_l_i_a_s_-_n_a_m_e operands specified did not represent a
             valid alias definition, or an error occurred.

CCOONNSSEEQQUUEENNCCEESS OOFF EERRRROORRSS
       Default.

       _T_h_e _f_o_l_l_o_w_i_n_g _s_e_c_t_i_o_n_s _a_r_e _i_n_f_o_r_m_a_t_i_v_e_.

AAPPPPLLIICCAATTIIOONN UUSSAAGGEE
       Since _u_n_a_l_i_a_s affects the current shell execution environment, it is
       generally provided as a shell regular built-in.

EEXXAAMMPPLLEESS
       None.

RRAATTIIOONNAALLEE
       The _u_n_a_l_i_a_s description is based on that from historical KornShell
       implementations.  Known differences exist between that and the C shell.
       The KornShell version was adopted to be consistent with all the other
       KornShell features in this volume of POSIX.1-2017, such as command line
       editing.

       The --aa option is the equivalent of the _u_n_a_l_i_a_s * form of the C shell
       and is provided to address security concerns about unknown aliases
       entering the environment of a user (or application) through the
       allowable implementation-defined predefined alias route or as a result
       of an _E_N_V file. (Although _u_n_a_l_i_a_s could be used to simplify the
       ``secure'' shell script shown in the _c_o_m_m_a_n_d rationale, it does not
       obviate the need to quote all command names. An initial call to _u_n_a_l_i_a_s
       --aa would have to be quoted in case there was an alias for _u_n_a_l_i_a_s.)

FFUUTTUURREE DDIIRREECCTTIIOONNSS
       None.

SSEEEE AALLSSOO
       _C_h_a_p_t_e_r _2, _S_h_e_l_l _C_o_m_m_a_n_d _L_a_n_g_u_a_g_e, _a_l_i_a_s

       The Base Definitions volume of POSIX.1-2017, _C_h_a_p_t_e_r _8, _E_n_v_i_r_o_n_m_e_n_t
       _V_a_r_i_a_b_l_e_s, _S_e_c_t_i_o_n _1_2_._2, _U_t_i_l_i_t_y _S_y_n_t_a_x _G_u_i_d_e_l_i_n_e_s

CCOOPPYYRRIIGGHHTT
       Portions of this text are reprinted and reproduced in electronic form
       from IEEE Std 1003.1-2017, Standard for Information Technology --
       Portable Operating System Interface (POSIX), The Open Group Base
       Specifications Issue 7, 2018 Edition, Copyright (C) 2018 by the
       Institute of Electrical and Electronics Engineers, Inc and The Open
       Group.  In the event of any discrepancy between this version and the
       original IEEE and The Open Group Standard, the original IEEE and The
       Open Group Standard is the referee document. The original Standard can
       be obtained online at http://www.opengroup.org/unix/online.html .

       Any typographical or formatting errors that appear in this page are
       most likely to have been introduced during the conversion of the source
       files to man page format. To report such errors, see
       https://www.kernel.org/doc/man-pages/reporting_bugs.html .



IEEE/The Open Group                  2017                           UNALIAS(1)
