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.