32v 1m chmod

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CHMOD(1) UNIX Programmer's Manual CHMOD(1)


NAME

    chmod - change mode

SYNOPSIS

    chmod mode file ...

DESCRIPTION

    The mode of each named file is changed according to _m_o_d_e,
    which may be absolute or symbolic.  An absolute _m_o_d_e 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 _c_h_m_o_d(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 _m_o_d_e has the form:
         [_w_h_o] _o_p _p_e_r_m_i_s_s_i_o_n [_o_p _p_e_r_m_i_s_s_i_o_n] ...
    The _w_h_o part is a combination of the letters u (for user's
    permissions), g (group) and o (other).  The letter a stands
    for ugo. If _w_h_o is omitted, the default is _a but the setting
    of the file creation mask (see umask(2)) is taken into
    account.
    _O_p can be + to add _p_e_r_m_i_s_s_i_o_n to the file's mode, - to take
    away _p_e_r_m_i_s_s_i_o_n and = to assign _p_e_r_m_i_s_s_i_o_n absolutely (all
    other bits will be reset).
    _P_e_r_m_i_s_s_i_o_n 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 _p_e_r_m_i_s_s_i_o_n
    is to be taken from the current mode.  Omitting _p_e_r_m_i_s_s_i_o_n
    is only useful with = to take away all permissions.
    The first example denies write permission to others, the
    second makes a file executable:
         chmod o-w file
         chmod +x file
    Multiple symbolic modes separated by commas may be given.
    Operations are performed in the order specified.  The letter
    s is only useful with u or g.
    Only the owner of a file (or the super-user) may change its
    mode.

SEE ALSO

    ls(1), chmod(2), chown (1), stat(2), umask(2)