TFile::Open(): distinguish application level and filesystem level errors

Dear ROOTers,

may I ask for your opinion about an issue concerning TFile::Open()?

I'm looking for a way to distinguish between application level and filesystem level errors in TFile::Open() because I'd like to ignore only the former in hadd. For the moment I'm thinking along the lines of adding another status bit in TFile, "kFSError" or similar, but as far as I've seen, further changes would be necessary, i.e. TFile::Open() could not return NULL anymore.

What do you think? Would you accept a patch?

The use case is: I'd like to merge large amounts of job-output-files, of which some are truncated because sometimes jobs are aborted. I'd like to ignore these truncated files without becoming blind to errors on the filesystem level, like eg. volume not mounted, or maximum number of open filedescriptors exceeded.

Cheers,
Thiemo

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| Dipl.-Phys. Thiemo Nagel          |                          |

| Technische Universitaet Muenchen  | Room    PH1 3276         |

| Physik-Department E18             |                          |

| James-Franck-Strasse              | Phone  +49 89 289-12379  |

| D-85747 Garching                  | Fax    +49 89 289-12570  |

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