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ls(1)

chmod(2)

stat(2)

umask(2)



CHMOD(1)                COMMAND REFERENCE                CHMOD(1)



NAME
     chmod - change mode of file or directory

SYNOPSIS
     chmod mode filename...

DESCRIPTION
     The mode of each named file is changed according to mode,
     which may be absolute or symbolic. Note that the examples
     given below for group and other permissions are simply the
     sum of the settings for read, write and execute given in the
     owner examples. An absolute mode is an octal number
     constructed from the OR of the following modes:

     4000 set user ID on execution

     2000 set group ID on execution

     1000 sticky bit, see chmod(2)

     0400 read by owner

     0200 write by owner

     0100 execute (search in directory) by owner

     0070 read, write, execute (search) by group

     0007 read, write, execute (search) by others

     A symbolic mode has the form:

          [who] op permission [op permission] ...

     The who part is a combination of the letters u (for user's
     permissions), g (group) and o (other).  The letter a stands
     for all, or ugo.  If who is omitted, the default is a but
     the setting of the file creation mask (see umask(2)) is
     taken into account.

     Op can be + to add permission to the file's mode, - (a minus
     sign) to take away permission,  and = (an equal sign) to
     assign permission absolutely (all other bits will be reset).

     Permission is any combination of the letters r (read), w
     (write), x (execute), s (set owner or group id) and t (save
     text - sticky). Letters u, g,  or o indicate that permission
     is to be taken from the current mode. Omitting permission is
     only useful with = to take away all permissions.

     Multiple symbolic modes separated by commas may be given.
     Operations are performed in the order specified. The letter



Printed 4/6/89                                                  1





CHMOD(1)                COMMAND REFERENCE                CHMOD(1)



     s is only useful with u or g.

     Only the owner of a file (or the superuser) may change its
     mode.

EXAMPLES
     The first example denies write permission to others; the
     second makes a file executable:

          chmod o-w file
          chmod +x file

     This example uses the permissions that are on for the group
     and turns them on for the user and others:

          chmod uo+g

RETURN VALUE
     [NO_ERRS]      Command completed without error.

     [USAGE]        Incorrect command line syntax. Execution
                    terminated.

     [NP_ERR]       An error occurred that was not a system
                    error.  Execution terminated.

     [P_WARN]       A system error occurred. Execution continues.
                    See intro(2) for more information on system
                    errors.

SEE ALSO
     ls(1), chmod(2), stat(2), and umask(2),























Printed 4/6/89                                                  2



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Typewritten Software • bear@typewritten.org • Edmonds, WA 98026