At present, the first file system to be mounted is the `In Memory File System'. It is mounted using a standard MOUNT() command in which the mount point is NULL. This flags the mount as the first file system to be registered under the operating system and appropriate initialization of file system management information is performed (See figures 4 and 5). If a different file system type is desired as the base file system, alterations must be made to base_fs.c. This routine handles the mount of the base file system.
Figure of the mount table chain goes here.
Once the root of the base file system has been established and it has been recorded as the mount point of the base file system, devices are integrated into the base file system. For every device that is configured into the system (See ioman.c) a device registration process is performed. Device registration produces a unique dev_t handle that consists of a major and minor device number. In addition, the configuration information for each device contains a text string that represents the fully qualified pathname to that device's place in the base file system's hierarchy. A file system node is created for the device along the specified registration path.
Figure of the Mount Table Processing goes here.
Note: Other file systems can be mounted but they are mounted onto points (directory mount points) in the base file system.
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