The index node (inode) of a Unix-like file system has 12 direct, one single-indirect and one double-indirect pointers

Q. The index node (inode) of a Unix-like file system has 12 direct, one single-indirect and one double-indirect pointers. The disk block size is 4 kB, and the disk block address is 32-bits long. The maximum possible file size is (rounded off to 1 decimal place) ____________GB.

Solution:

No. of Disk block pointers = 4kB/32bits = 1k
Max. file size
= (12 × 1k + 1k × 1k) × 4kB

≈ (1024 × 12 + 1024 × 1024) × 4 × 1024 bytes
≈ 4GB