Why do inode number start from 1 and not 0 ?

Question Posted / niteshtirkey

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Why do inode number start from 1 and not 0 ?..

Answer / satish

1) All block and inode addresses start at 1. The first
block on the disk is block 1. 0 is used to indicate no
block.
2)0 is used as a sentinel value to indicate null or no
inode. similar to how pointers can be NULL in C. without a
sentinel, you'd need an extra bit to test if an inode in a
struct was set or not.

Is This Answer Correct ?

17 Yes

2 No

Why do inode number start from 1 and not 0 ?..

Answer / virupakshicm

0 indicates no inode. We know that directory contains data
in the form of entries and each entry contains inode number
and filename. Suppose if we delete a particular file from
the directory, then that entries inode number will be
changed to 0, indicating that this particular entry is
free. So when the next file is created under the directory,
then the kernel uses this entry for the new file and it
also changes the filename component to new name. This is
reason why inode 0 is not used.

Is This Answer Correct ?

14 Yes

1 No

Why do inode number start from 1 and not 0 ?..

Answer / khaja

BECAUZ INODE HAS DISK BLOCKS WHICH START FROM 0 ie: inode
is 1.

Is This Answer Correct ?

4 Yes

7 No

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