A CDE Definition
(CHange MODe) A Unix command that changes the permissions (attributes) of a file or directory. Chmod requires an understanding of how the read-write-execute permissions are expressed. The "list long" command (ls -l) displays the attributes of a file or directory, and the first part of the line looks like this: -rwxrwxrwx. A dash or "d" as the first character means file or directory. The three sets of rwx are permissions for owner-group-other. For example, -rwxrw-r-- gives all permissions to the file on the line to the owner, read/write permissions to the group and read only for the rest.
The command uses =, + and - to set, add and subtract changes to owner (u), group (g), other (o) or all (a). The following examples show the permissions of an abc.sh shell script after each command is executed. See ls, shell script, chown and chgrp.
-rwxrwxrwx ALL PERMISSIONS
chmod o= abc.sh SET OTHER TO NONE
chmod o+r abc.sh ADD R TO OTHER
chmod a-x abc.sh REMOVE ALL EXECUTE
chmod a=rwx abc.sh SET ALL TO RWX
chmod a= abc.sh SET ALL TO NON
chmod u=r abc.sh SET OWNER TO READ
List Long Shows Permissions
Before/After Your Search Term
|chips and salsa||Chooser|
|chipset graphics||chorded keyboard|
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