root@bt:~/test# ln --helpUsage: ln [OPTION]... [-T] TARGET LINK_NAME (1st form) or: ln [OPTION]... TARGET (2nd form) or: ln [OPTION]... TARGET... DIRECTORY (3rd form) or: ln [OPTION]... -t DIRECTORY TARGET... (4th form)In 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.When creating hard links, each TARGET must exist. Symbolic linkscan hold arbitrary text; if later resolved, a relative link isinterpreted in relation to its parent directory.Mandatory arguments to long options are mandatory for short options too. --backup[=CONTROL] make a backup of each existing destination file -b like --backup but does not accept an argument -d, -F, --directory allow the superuser to attempt to hard link directories (note: will probably fail due to system restrictions, even for the superuser) -f, --force remove existing destination files -n, --no-dereference treat destination that is a symlink to a directory as if it were a normal file -i, --interactive prompt whether to remove destinations -s, --symbolic make symbolic links instead of hard links -S, --suffix=SUFFIX override the usual backup suffix -t, --target-directory=DIRECTORY specify the DIRECTORY in which to create the links -T, --no-target-directory treat LINK_NAME as a normal file -v, --verbose print name of each linked file --help display this help and exit --version output version information and exitThe backup suffix is `~', unless set with --suffix or SIMPLE_BACKUP_SUFFIX.The version control method may be selected via the --backup option or throughthe VERSION_CONTROL environment variable. Here are the values: 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