Identifying a file by its inode number

In addition to its file name, each file in a file system has an identification number, called an inode number, that is unique in its file system. The inode number refers to the physical file, the data stored in a particular location. A file also has a device number, and the combination of its inode number and device number is unique throughout all the file systems in the hierarchical file system.

A directory entry joins a file name with the inode number that represents the physical file.

To display the inode numbers of the files in your working directory, enter:

ls -i

If Alice Smith issues that command for her proja directory, she sees the following display:

1077 inspproc   1077 isoproc    1492 kgnproc   1500 mcrproc

Because the files inspproc and isoproc are hard-linked, they have the same inode number.