To change permissions for an item, use the chmod command. The syntax of the command is as follows:
chmod securitygroup [changetype] [permission] [file or directory]
u - user
g - group
o - other
all - all
The options for each item in the command are as follows.
securitygroup (The person or group whose permission you are changing)
changetype (For adding or subtracting a permission)
“+” add permission
“-” subtract permission
permission (The permission you are changing)
r - read
w - write
x - execute
file or directory (The name of the file or directory to change)
Here are some chmod examples:
To remove write access for group and others for the file myfile, enter:
chmod go-w myfile
To add read and write access for group and others for the files myfile1 and myfile2, enter:
chmod go+rw myfile1 myfile2
To add read, write, and execute access for everyone for myfile1 enter:
chmod ugo+rwx myfile1
For more information on changing UNIX permissions, see the chmod man page by entering “man chmod” in the Terminal window.