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n the 1st form, create a link to TARGET with the name LINK_NAME. In the 2nd form, create a link to TARGET in the current directory. In the 3rd and 4th forms, create links to each TARGET in DIRECTORY. Create hard links by default, symbolic links with –symbolic.

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–backup[=CONTROL]
-b
–backup[=CONTROL], Make a backup of each existing destination file.
CONTROL: none, off = Never make backups (even if –backup is given)
numbered, t = make numbered backups
existing, nil = numbered if numbered backups exist, simple otherwise
simple, never = always make simple backups
-b, Like –backup with no arguments.
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