chmod - change file mode (permissions) chmod mode file ... 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): .TF 0000

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), x (execute), a (append only), l (exclusive access), and t (temporary, not archived).

/appl/cmd/chmod.b

chgrp (1), ls (1), sys-stat (2) The interpretation of the modes is limited on some host operating systems, particularly variants of Windows.