rootfs is basically the root file system(/ directory of N9). The OS data resides here.
The
DFL61_HARMATTAN_40.2012.21-3_PR_LEGACY_001-OEM1-958_ARM.bin
is used to flash this area as it contains the OS Data. This file is referred to as rootfs file or just rootfs.
This is similar to ROFS in Symbian.


The other file
DFL61_HARMATTAN_40.2012.13-7.FRANCEBENELUX_EMMC_FRANCEBENELUX.bin
is the file that contains Maps data, Music, Pictures depending on your Country/Product Code. This goes into the /home/user/MyDocs directory.

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