How to detect not closed file added to TChain

ROOT
1

Dear ROOT-Experts,

(root version 5.14/00e)

is it possible to detect a root file (in a TChain), which was “probably not closed”?

The background to this question is:
In my analysis code, I am adding a large number of files to a chain using a wildcard.
One of this input files got somehow corrupted. Because of that corrupted file, a warning is printed when the contents of the chain are accessed.
But than the root file is (only partially) recovered and my program continues.

The root session below illustrates what happens:

root [0] TChain * chain = new TChain("ntp1011"); root [1] chain->Add("Tau11-tau-run4-*.root") (Int_t)1 root [2] chain->GetEntries() Warning in <TFile::Init>: file Tau11-tau-run4-90.root probably not closed, trying to recover Info in <TFile::Recover>: Tau11-tau-run4-90.root, recovered key TDirectory:PreMicroCuts at address 442 Info in <TFile::Recover>: Tau11-tau-run4-90.root, recovered key TDirectory:PreSelHistos at address 565 Info in <TFile::Recover>: Tau11-tau-run4-90.root, recovered key TDirectory:DecayModes at address 688 Info in <TFile::Recover>: Tau11-tau-run4-90.root, recovered key TDirectory:PostMicroCuts at address 807 Info in <TFile::Recover>: Tau11-tau-run4-90.root, recovered key TDirectory:TopCheckerHistos at address 932 Info in <TFile::Recover>: Tau11-tau-run4-90.root, recovered key TDirectory:Pi0Histograms at address 1063 Info in <TFile::Recover>: Tau11-tau-run4-90.root, recovered key TDirectory:conversionshistos at address 1190 Info in <TFile::Recover>: Tau11-tau-run4-90.root, recovered key TDirectory:NanoHistos at address 1323 Info in <TFile::Recover>: Tau11-tau-run4-90.root, recovered key TTree:ntp1011 at address 215743522 Warning in <TFile::Init>: successfully recovered 9 keys (const Long64_t)66487364

My problem is, that despite the recovery, the output of my program is useless because of lost contents in the corrupted input file.
Currently, I have to search my log files for the warning given above to detect if there were corrupted input files.

What I would like to do instead is something like that:

[code]{

TChain * chain = new TChain(“ntp1011”);

chain->Add(“Tau11-tau-run4-*.root”)

if( chain->ContainsFileWhichWasNotClosed() ){

 exit the program

}
else{

 go on

}

}[/code]

Thank you in advance for any hint how to do that.

Best regards,
Aleks

2

Before adding the file to the TChain, you should check if it is a valid file or if it has been recovered with a piece of code looking loke

while (filename=...) { TFile *file = TFile::Open(filename); if (!file) continue ; //file does not exist if (file->IsZombie()) continue; //file is unusable if (file->testBit(TFile::kRecovered)) continue; //file has been recovered delete file; chain.Add(filename); }
Rene

3

Dear Rene,

thank you very much.

The line file->TestBit(TFile::kRecovered) was the missing piece to solve the problem.

Best regards,
Aleks