Funlinkat

If in a process we open the same file (inode) using different names (for example through hard links) all those files will be linked to the single vnode. Another problem is more architectural: as we discussed earlier unlinking is really an operation on the directory not on the file (inode) itself, so using funlink(fd) may create some confusion because we are not removing the inode corresponding to the file descriptor, we are performing action on the directory which points to the file. This syscall would only performs additional sanitary checks if we are removing a directory entry which corresponds to the inode stored which refers to the file descriptor.

Source: oshogbo.vexillium.org