


CHMOD(1L)                                               CHMOD(1L)


NNAAMMEE
       chmod - change the access permissions of files

SSYYNNOOPPSSIISS
       cchhmmoodd [-Rcfv] mode file...

DDEESSCCRRIIPPTTIIOONN
       This  manual  page  documents  the  GNU  version of cchhmmoodd.
       cchhmmoodd changes the permissions of each given file according
       to  _m_o_d_e, which can be either a symbolic representation of
       changes to make, or an octal number representing  the  bit
       pattern for the new permissions.

       The      format      of     a     symbolic     mode     is
       `[ugoa...][[+-=][rwxXstugo...]...][,...]'.  Multiple  sym-
       bolic operations can be given, separated by commas.

       A  combination of the letters `ugoa' controls which users'
       access to the file will be changed: the user who  owns  it
       (u),  other users in the file's group (g), other users not
       in the file's group (o), or all users  (a).   If  none  of
       these  are  given, the effect is as if `a' were given, but
       bits that are set in the umask are not affected.

       The operator `+' causes the  permissions  selected  to  be
       added to the existing permissions of each file; `-' causes
       them to be removed; and `=' causes them  to  be  the  only
       permissions that the file has.

       The letters `rwxXstugo' select the new permissions for the
       affected users: read (r), write (w),  execute  (or  access
       for directories) (x), execute only if the file is a direc-
       tory or already has execute permission for some user  (X),
       set  user  or group ID on execution (s), save program text
       on swap device (t), the permissions that the user who owns
       the  file  currently  has for it (u), the permissions that
       other users in the file's group have for it (g),  and  the
       permissions  that other users not in the file's group have
       for it (o).

       A numeric mode is from one to  four  octal  digits  (0-7),
       derived  by  adding  up  the bits with values 4, 2, and 1.
       Any omitted digits are assumed to be leading  zeros.   The
       first  digit  selects the set user ID (4) and set group ID
       (2) and save text image (1) attributes.  The second  digit
       selects  permissions  for the user who owns the file: read
       (4), write (2), and execute (1); the third selects permis-
       sions  for  other users in the file's group, with the same
       values; and the fourth for other users not in  the  file's
       group, with the same values.

       cchhmmoodd ignores symbolic links; the cchhmmoodd system call cannot
       change their permissions.  This is not a problem since the
       permissions of symbolic links are never used.



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CHMOD(1L)                                               CHMOD(1L)


   OOPPTTIIOONNSS
       _-_c     Verbosely  describe  only  files  whose permissions
              actually change.

       _-_f     Do not print error messages about files whose  per-
              missions cannot be changed.

       _-_v     Verbosely describe changed permissions.

       _-_R     Recursively  change  permissions of directories and
              their contents.














































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