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



PROLOG
       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.

NAME
       chgrp -- change the file group ownership

SYNOPSIS
       chgrp [[-h]] group file...

       chgrp -R [[-H|-L|-P]] group file...

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

       For each file operand, or, if the -R option is used, each file
       encountered while walking the directory trees specified by the file
       operands, the chgrp utility shall perform actions equivalent to the
       chown() function defined in the System Interfaces volume of
       POSIX.1-2017, called with the following arguments:

        *  The file operand shall be used as the path argument.

        *  The user ID of the file shall be used as the owner argument.

        *  The specified group ID shall be used as the group argument.

       Unless chgrp is invoked by a process with appropriate privileges, the
       set-user-ID and set-group-ID bits of a regular file shall be cleared
       upon successful completion; the set-user-ID and set-group-ID bits of
       other file types may be cleared.

OPTIONS
       The chgrp utility shall conform to the Base Definitions volume of
       POSIX.1-2017, Section 12.2, Utility Syntax Guidelines.

       The following options shall be supported by the implementation:

       -h        For each file operand that names a file of type symbolic
                 link, chgrp shall attempt to set the group ID of the symbolic
                 link instead of the file referenced by the symbolic link.

       -H        If the -R option is specified and a symbolic link referencing
                 a file of type directory is specified on the command line,
                 chgrp shall change the group of the directory referenced by
                 the symbolic link and all files in the file hierarchy below
                 it.

       -L        If the -R option is specified and a symbolic link referencing
                 a file of type directory is specified on the command line or
                 encountered during the traversal of a file hierarchy, chgrp
                 shall change the group of the directory referenced by the
                 symbolic link and all files in the file hierarchy below it.

       -P        If the -R option is specified and a symbolic link is
                 specified on the command line or encountered during the
                 traversal of a file hierarchy, chgrp shall change the group
                 ID of the symbolic link. The chgrp utility shall not follow
                 the symbolic link to any other part of the file hierarchy.

       -R        Recursively change file group IDs. For each file operand that
                 names a directory, chgrp shall change the group of the
                 directory and all files in the file hierarchy below it.
                 Unless a -H, -L, or -P option is specified, it is unspecified
                 which of these options will be used as the default.

       Specifying more than one of the mutually-exclusive options -H, -L, and
       -P shall not be considered an error. The last option specified shall
       determine the behavior of the utility.

OPERANDS
       The following operands shall be supported:

       group     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 file operands. If a numeric group 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.

       file      A pathname of a file whose group ID is to be modified.

STDIN
       Not used.

INPUT FILES
       None.

ENVIRONMENT VARIABLES
       The following environment variables shall affect the execution of
       chgrp:

       LANG      Provide a default value for the internationalization
                 variables that are unset or null. (See the Base Definitions
                 volume of POSIX.1-2017, Section 8.2, Internationalization
                 Variables for the precedence of internationalization
                 variables used to determine the values of locale categories.)

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

       LC__CTYPE  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).

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

       NLSPATH   Determine the location of message catalogs for the processing
                 of LC__MESSAGES.

ASYNCHRONOUS EVENTS
       Default.

STDOUT
       Not used.

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

OUTPUT FILES
       None.

EXTENDED DESCRIPTION
       None.

EXIT STATUS
       The following exit values shall be returned:

        0    The utility executed successfully and all requested changes were
             made.

       >0    An error occurred.

CONSEQUENCES OF ERRORS
       Default.

       The following sections are informative.

APPLICATION USAGE
       Only the owner of a file or the user with appropriate privileges may
       change the owner or group of a file.

       Some implementations restrict the use of chgrp to a user with
       appropriate privileges when the group specified is not the effective
       group ID or one of the supplementary group IDs of the calling process.

EXAMPLES
       None.

RATIONALE
       The System V and BSD versions use different exit status codes. Some
       implementations used the exit status as a count of the number of errors
       that occurred; this practice is unworkable since it can overflow the
       range of valid exit status values. The standard developers chose to
       mask these by specifying only 0 and >0 as exit values.

       The functionality of chgrp is described substantially through
       references to chown().  In this way, there is no duplication of effort
       required for describing the interactions of permissions, multiple
       groups, and so on.

FUTURE DIRECTIONS
       None.

SEE ALSO
       chmod, chown

       The Base Definitions volume of POSIX.1-2017, Chapter _8, Environment
       Variables, Section 12.2, Utility Syntax Guidelines

       The System Interfaces volume of POSIX.1-2017, chown()

COPYRIGHT
       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                             CHGRP(1)
