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Practical UNIX by Steve Moritsugu - DTR Business Systems

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Changing Permissions/Owner/Group

Permissions of files and directories can be changed using the command chmod (change mode). This command can either be used with a numerical argument, which states exactly what the permission should be, or with a symbolic argument, which may change only part of the permissions (such as only the permissions for the user). Here is the general syntax of the chmod command:

chmod perm-changes file1 file2 ...

perm-changes specifies what permissions to change and may be specified in either numeric or symbolic mode, as you shall see shortly.

Only the user who owns a given file may change the permissions for this file. (An exception to this rule is, of course, the superuser, who may do anything!)

The chmod program changes ...

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