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IDs

Each file in Chimera has a unique 18 byte long ID. It is referred to as ChimeraID or as pnfsID. This is comparable to the inode number in other filesystems. The ID used for a file will never be reused, even if the file is deleted. dCache uses the ID for all internal references to a file.

Example:

The ID of the file example.org/data/examplefile can be obtained by reading the command-file .(id)(examplefile) in the directory of the file.

[user] $ cat /example.org/data/'.(id)(examplefile)'
0000917F4A82369F4BA98E38DBC5687A031D

A file in Chimera can be referred to by the ID for most operations.

Example:

The name of a file can be obtained from the ID with the command nameof as follows:

[user] $ cd /example.org/data/
[user] $ cat '.(nameof)(0000917F4A82369F4BA98E38DBC5687A031D)'
examplefile

And the ID of the directory it resides in is obtained by:

[user] $ cat '.(parent)(0000917F4A82369F4BA98E38DBC5687A031D)'
0000595ABA40B31A469C87754CD79E0C08F2

This way, the complete path of a file may be obtained starting from the ID.