Storing and accessing files at Glasgow
If you are a user in a supported VO use LCG Utils in the normal way to get files to and from Glasgow's SE.
The hostname you need to use is
rfio: Optimised Local Access
Caveat: Really access via RFIO should probably be provided within the VO's analysis framework, but here are a few pointers if you want to use RFIO calls in your own code...
[LCG Utils]] methods are fine for copying whole files to and from the SE. However, to get a more posix-like i/o (e.g. read only a section of a file) on files stored in the SE you will need to use the RFIO libraries. Using RFIO will give you much faster and more flexible access to your files.
Filenames in RFIO Space
These are like the normal SURLs, but with the hostname and port removed:
- srm://svr018.gla.scotgrid.ac.uk:8443/dpm/gla.scotgrid.ac.uk/home/atlas/file -> /dpm/gla.scotgrid.ac.uk/home/atlas/file
RFIO Client Tools
There are a few RFIO client tools, e.g., rfcat, rfcat, which can be used.
The libraries and headers for DPM are stored in the DPM-client RPM, so this is a quick way of listing the available API calls:
rpm -ql DPM-client ... man rfio_fopen
Each of the part of the API are documented in a manual page.
The CASTOR User Guide contains an RFIO programing example at the end, which should work for DPM, but I haven't tried it...