Final answer:
Devfs is the file system used as a virtual system to maintain devices on the fly.
Step-by-step explanation:
The file system used as a virtual system to maintain devices on the fly is devfs.
Devfs stands for device file system and it is a virtual file system in Unix-like operating systems that provides an interface to device drivers and other device-specific information.
Devfs dynamically creates and manages device files in the /dev directory, allowing devices to be accessed by their names instead of their device numbers.
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