		 IEEE P1003.2 Draft 11.2 - September 1991


			Copyright (c) 1991 by the
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 P1003.2/D11.2                               INFORMATION TECHNOLOGY--POSIX

 4.5  cd - Change working directory


 4.5.1  Synopsis


 cd  [_d_i_r_e_c_t_o_r_y]


 4.5.2  Description

 The cd utility shall change the working directory of the current shell
 execution environment; see 3.12.

 When invoked with no operands, and the HOME environment variable is set
 to a nonempty value, the directory named in the HOME environment variable
 shall become the new working directory.  If HOME is empty or is
 undefined, the default behavior is implementation defined.


 4.5.3  Options

 None.


 4.5.4  Operands

 The following operands shall be supported by the implementation:

    _d_i_r_e_c_t_o_r_y   An absolute or relative pathname of the directory that
                becomes the new working directory.  The interpretation of
                a relative pathname by cd depends on the CDPATH
                environment variable.  If _d_i_r_e_c_t_o_r_y is -, the results are
                implementation defined.


 4.5.5  External Influences

 4.5.5.1  Standard Input

 None.


 4.5.5.2  Input Files

 None.





               Copyright c 1991 IEEE.  All rights reserved.
      This is an unapproved IEEE Standards Draft, subject to change.





 388                                     4 Execution Environment Utilities





 Part 2: SHELL AND UTILITIES                                 P1003.2/D11.2

 4.5.5.3  Environment Variables

 The following environment variables shall affect the execution of cd:

    CDPATH             A colon-separated list of pathnames that refer to
                       directories.  If the _d_i_r_e_c_t_o_r_y operand does not
                       begin with a slash (/) character, and the first
                       component is not dot or dot-dot, cd shall search
                       for _d_i_r_e_c_t_o_r_y relative to each directory named in
                       the CDPATH variable, in the order listed.  The new
                       working directory shall be set to the first
                       matching directory found.  An empty string in place
                       of a directory pathname represents the current
                       directory.  If CDPATH is not set, it shall be
                       treated as if it were an empty string.

    HOME               The name of the home directory, used when no
                       _d_i_r_e_c_t_o_r_y operand is specified.

    LANG               This variable shall determine the locale to use for
                       the locale categories when both LC_ALL and the
                       corresponding environment variable (beginning with
                       LC_) do not specify a locale.  See 2.6.

    LC_ALL             This variable shall determine the locale to be used
                       to override any values for locale categories
                       specified by the settings of LANG or any
                       environment variables beginning with LC_.

    LC_CTYPE           This variable shall determine the locale for the
                       interpretation of sequences of bytes of text data
                       as characters (e.g., single- versus multibyte
                       characters in arguments).

    LC_MESSAGES        This variable shall determine the language in which
                       messages should be written.


 4.5.5.4  Asynchronous Events

 Default.


 4.5.6  External Effects







               Copyright c 1991 IEEE.  All rights reserved.
      This is an unapproved IEEE Standards Draft, subject to change.





 4.5 cd - Change working directory                                     389





 P1003.2/D11.2                               INFORMATION TECHNOLOGY--POSIX

 4.5.6.1  Standard Output

 If a nonempty directory name from CDPATH is used, an absolute pathname of
 the new working directory shall be written to the standard output as
 follows:

       "%s\n", <_n_e_w _d_i_r_e_c_t_o_r_y>

 Otherwise, there shall be no output.


 4.5.6.2  Standard Error

 Used only for diagnostic messages.

 4.5.6.3  Output Files

 None.


 4.5.7  Extended Description

 None.


 4.5.8  Exit Status

 The cd utility shall exit with one of the following values:

     0    The directory was successfully changed.

    >0    An error occurred.


 4.5.9  Consequences of Errors

 The working directory remains unchanged.

 BEGIN_RATIONALE


 4.5.10  Rationale. (_T_h_i_s _s_u_b_c_l_a_u_s_e _i_s _n_o_t _a _p_a_r_t _o_f _P_1_0_0_3._2)

 _E_x_a_m_p_l_e_s_,__U_s_a_g_e

 _E_d_i_t_o_r'_s _N_o_t_e:  _A _b_a_l_l_o_t_e_r _r_e_q_u_e_s_t_e_d _t_h_a_t _t_h_e _f_o_l_l_o_w_i_n_g _r_a_t_i_o_n_a_l_e _b_e       2
 _h_i_g_h_l_i_g_h_t_e_d _i_n _t_h_e _D_1_1._2 _r_e_c_i_r_c_u_l_a_t_i_o_n.                                    2




               Copyright c 1991 IEEE.  All rights reserved.
      This is an unapproved IEEE Standards Draft, subject to change.





 390                                     4 Execution Environment Utilities





 Part 2: SHELL AND UTILITIES                                 P1003.2/D11.2

 Since cd affects the current shell execution environment, it is generally
 provided as a shell regular built-in.  If it is called in a subshell or    1
 separate utility execution environment, such as one of the following:      1

       (cd /tmp)                                                            1
       nohup cd                                                             1
       find . -exec cd {} \;                                                1

 it will not affect the working directory of the caller's environment.      1

 The use of the CDPATH was introduced in the System V shell.  Its use is
 analogous to the use of the PATH variable in the shell.  Earlier systems
 such as the BSD C-shell used a shell parameter cdpath for this purpose.

 _H_i_s_t_o_r_y__o_f__D_e_c_i_s_i_o_n_s__M_a_d_e

 A common extension when HOME is undefined is to get the login directory
 from the user database for the invoking user.  This does not occur on
 System V implementations.

 Not included in this description are the features from the KornShell such
 as setting OLDPWD, toggling current and previous directory (cd -), and
 the two-operand form of cd (cd _o_l_d _n_e_w). This standard does not specify
 the results of cd - or of calls with more than one operand.  Since these
 extensions are mostly used in interactive situations, they may be
 considered for inclusion in POSIX.2a.  The result of cd - and of using no
 arguments with HOME unset or null have been made implementation defined
 at the request of the POSIX.6 security working group.

 The setting of the PWD variable was removed from earlier drafts, as it
 can be replaced by $(pwd).

 END_RATIONALE


















               Copyright c 1991 IEEE.  All rights reserved.
      This is an unapproved IEEE Standards Draft, subject to change.





 4.5 cd - Change working directory                                     391





 P1003.2/D11.2                               INFORMATION TECHNOLOGY--POSIX

 4.6  chgrp - Change file group ownership


 4.6.1  Synopsis


 chgrp  [-R] _g_r_o_u_p _f_i_l_e ...


 4.6.2  Description

 The chgrp utility shall set the group ID of the file named by each _f_i_l_e
 operand to the group ID specified by the _g_r_o_u_p operand.

 For each _f_i_l_e operand, it shall perform actions equivalent to the
 POSIX.1 {8} _c_h_o_w_n() function, called with the following arguments:

     (1)  The _f_i_l_e operand shall be used as the _p_a_t_h argument.

     (2)  The user ID of the file shall be used as the _o_w_n_e_r argument.

     (3)  The specified _g_r_o_u_p _I_D shall be used as the _g_r_o_u_p argument.


 4.6.3  Options

 The chgrp utility shall conform to the utility argument syntax guidelines
 described in 2.10.2.

 The following option shall be supported by the implementation:

    -R          Recursively change file group IDs.  For each _f_i_l_e operand
                that names a directory, chgrp shall change the group of
                the directory and all files in the file hierarchy below
                it.


 4.6.4  Operands

 The following operands shall be supported by the implementation:

    _g_r_o_u_p       A group name from the group database or a numeric group
                ID.  Either specifies a group ID to be given to each file
                named by one of the _f_i_l_e operands.  If a numeric _g_r_o_u_p
                operand exists in the group database as a group name, the
                group ID number associated with that group name is used as
                the group ID.




               Copyright c 1991 IEEE.  All rights reserved.
      This is an unapproved IEEE Standards Draft, subject to change.





 392                                     4 Execution Environment Utilities


