NAME

chmod − change file mode (permissions)

SYNOPSIS

­chmod ­mode ­file ... 

DESCRIPTION

­Chmod changes the mode (permissions) of each ­file according to mode, which may be an octal number or a symbolic change to the existing mode.

A ­mode can be numerically formed as the OR of the following octal values (a leading ­8r is ignored):

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

The ­who part is a combination of the letters ­u (for user’s permissions), ­g (group) and ­o (other).  The letter ­a stands for ugo.  If ­who is omitted, the default is a. 

The ­op field can be: ­+ to add ­permission to the file’s mode, ­- to take away permission, ­= to assign ­permission absolutely (all other bits being reset). 

The ­permission field is any combination of the letters ­r (read), ­w (write), and ­x (execute). 

SOURCE

­/appl/cmd/chmod.b

SEE ALSO

ls(1), sys-stat(2)

BUGS

The interpretation of the modes is limited on some host operating systems, particularly variants of Windows. 

Plan 9  —  June 29, 2000