Changing permissions using chmod command

At one time a file is created the umask value no longer has any affect on it. Within order to modify the permissions of a file the chmod command must be used. Only the owner (or root) of a file can modify its permissions.

chmod has two modes that are as below, " absolute " and " symbolic ".

Within symbolic mode, permissions could be granted or revoked through using the symbols "+, -, = ". Within absolute mode, permissions are set through the desired octal value for the file permissions.

Access to a file might also be affected through using the CHMOD command. Only the owner (or root) of a file can modify its group membership.

The file owner can modify the group of a file only if the owner is a member of the group.

Syntax

chmod [ -fR ] <absolute-mode> file ...

chmod [ -fR ] <symbolic-mode-list> file ...

chmod   assigns or changes the mode of a file. The mode of a file specifies its permission and other attributes. The mode might be symbolic or absolute.