o sinalizador -o
indica a opção "opções".
Flags Item Description
-b Boot Names the program to be installed in block 0 of the new file system.
-i i-Nodes Specifies the initial number of i-nodes on the file system. This flag is ignored when creating a journaled file system.
-l Label Specifies the file system label for the new file system.
-o Options Specifies a comma-separated list of virtual file system implementation-specific options.