NAME

     chmod - change access mode for files


SYNOPSIS

     chmod [-R] mode file ...


OPTIONS

     -R   Change hierarchies recursively


EXAMPLES

     chmod 755 file      # Owner: rwx Group: r-x Others: r-x

     chmod +x file1 file2
                         # Make file1 and file2 executable

     chmod a-w file      # Make file read only

     chmod u+s file      # Turn on SETUID for file

     chmod -R o+w dir    # Allow writing for all files in dir


DESCRIPTION

     The given mode is applied to each file in the file list.  If
     the  -R  flag  is  present, the files in a directory will be
     changed as well.  The mode can be either  absolute  or  sym-
     bolic.  Absolute  modes  are  given  as an octal number that
     represents the new file mode. The mode bits are  defined  as
     follows:

       4000    Set effective user id on execution to file's owner id
       2000    Set effective group id on execution to file's group id
       0400    file is readable by the owner of the file
       0200    writeable by owner
       0100    executable by owner
       0070    same as above, for other users in the same group
       0007    same as above, for all other users

     Symbolic modes modify the current file mode in  a  specified
     way. The form is:

       [who] op permissions { op permissions ...} {, [who] op ...
     }

     The possibilities for who are u, g, o, and a,  standing  for
     user, group, other and all, respectively. If who is omitted,
     a is assumed, but the current umask is used. The op  can  be
     +,  -, or =;  + turns on the given permissions, - turns them
     off; = sets the permissions exclusively for the  given  who.
     For example g=x sets the group permissions to --x.

     The possible permissions are r, w, x; which stand for  read,
     write, and execute;  s turns on the set effective user/group
     id bits. s only makes sense with u and g; o+s is harmless.


SEE ALSO

     ls(1), chmod(2).