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chgrp(1)

ls(1)

sys-stat(2)

CHMOD(1)

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

SOURCE

/appl/cmd/chmod.b

SEE ALSO

chgrp(1), ls(1), sys-stat(2)

BUGS

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

Typewritten Software • bear@typewritten.org • Edmonds, WA 98026