IceTop detector simulation: I3CorsikaInjector and .bz2 files

[olivas]

Moving this from Trac.

Hi everyone,
i have a technical question concerning the read-in of compressed CORSIKA files (.bz2) for the IceTop? detector simulation. I use the simulation sets 10410 and 10889.
I learned that the current version of the I3CorsikaInjector can not treat bz2 files.
Thus i build the following solution:

1. Copy the compressed CORSIKA file .bz2 file to my directory
2. Unpack it
3. Use it
4. Delete it
   This solution works fine but it is very, very time consuming. Copying & unpacking bz2 files limits the number of jobs i can run in parallel to a very small number because i easily exceed 1TB (i already have some hundreds of GB of data which i really need). I want to run more jobs in parallel, because otherwise i still need months to finish my detector simulation. I do not have this time :(
   The detector simulation i do bases on the detector response of different particle types (separately!) and anyway takes more time than a "usual" simulation.
   Is there a solution? Are there some lines of code i can add in order to make I3CorsikaInjector treat .bz2 files? I heard that it may be possible when "if stream" is changed to "boost::iostreams::filtering_istream", but i am completely unfamiliar with this.
   Can you please help me?
   Cheers, Daniel