[Libguestfs] mount device of 'unknow' filesystem type

hi all! some windows vm's filesystem type is unknown(/dev/sda: unknown), and 'mount' command leads to: 'libguestfs: error: mount: /dev/sda on / (options: ''): mount: you must specify the filesystem type ' if i don't know the type, whether i could mount the device? Thanks! 周涛 --------------------------------------------------------------------------------------------------- Confidentiality Notice: The information contained in this e-mail and any accompanying attachment(s) is intended only for the use of the intended recipient and may be confidential and/or privileged of Neusoft Corporation, its subsidiaries and/or its affiliates. If any reader of this communication is not the intended recipient, unauthorized use, forwarding, printing, storing, disclosure or copying is strictly prohibited, and may be unlawful.If you have received this communication in error,please immediately notify the sender by return e-mail, and delete the original message and all copies from your system. Thank you. ---------------------------------------------------------------------------------------------------