Yes, thanks very much.
Cheers.
Paolo

On Nov 28, 2013, at 12:20 AM, Olivier Mattelaer <email address hidden> wrote:

> Thanks a lot for the investigation.
> 
> Cheers,
> 
> Olivier
> On Nov 27, 2013, at 10:29 PM, Pavel Demin <email address hidden> wrote:
> 
>> I've just looked at the mcfio/stdhep code includedd with the pythia-pgs
>> package in MG5.
>> 
>> The code in pythia-pgs/src/pythia.f calls the following chain of
>> functions to write an event:
>> 
>> 1. stdxwrt defined in pythia-pgs/libraries/PGS4/src/stdhep-dir/src/stdhep/stdxwrt.F
>> 2. stdxwevt defined in pythia-pgs/libraries/PGS4/src/stdhep-dir/src/stdhep/stdxwevt.F
>> 3. mcfio_block defined in pythia-pgs/libraries/PGS4/src/stdhep-dir/mcfio/src/mcfio_Block.c
>> 
>> Then he mcfio_block function uses the xdr_getpos and xdr_setpos
>> functions from the XDR library. These functions are used to get and set
>> postion in the output file.
>> 
>> The problem is that these functions operate on 32-bit values and return
>> 32-bit values. When the position in file reaches the 4GB limit, the
>> 32-bit position overflows and the mcfio/sdthep librarry starts to write
>> events in the very beginning of the file and thus corrupts the file
>> header.
>> 
>> So, my conclusion is that the mcfio/stdhep library used by the pythia-
>> pgs/src/pythia.f program can't work with files larger than 4GB.
>> 
>> -- 
>> You received this bug notification because you are a member of MadTeam,
>> which is subscribed to MadGraph5.
>> https://bugs.launchpad.net/bugs/1218842
>> 
>> Title:
>> STDHEP files larger than 4GB are corrupted
>> 
>> Status in The MadGraph Matrix Element Generator version 5:
>> Confirmed
>> 
>> Bug description:
>> I've just tested several STDHEP files produced by MG+HERWIG6.
>> 
>> I've tested 50MB, 3.3GB and 4.0GB files.
>> 
>> The 50MB and 3.3GB files can be read without any problem.
>> 
>> The 4.0GB file can't be read.
>> 
>> In the 4.0GB file, already the 2nd block has a block ID number equal
>> 2. Normally, it should be 4 (Event Header). The following blocks have
>> completely wrong block ID numbers. So, I'd say that it's corrupted
>> from the very beginning.
>> 
>> In some cases, adding the following compilation flag helps:
>> 
>> -D_FILE_OFFSET_BITS=64
>> 
>> Normally, the STDHEP library and maybe the PYTHIA and HERWIG
>> interfaces should be compiled with this flag.
>> 
>> If you can tell me where to put this flag, I can redo the test.
>> 
>> To manage notifications about this bug go to:
>> https://bugs.launchpad.net/madgraph5/+bug/1218842/+subscriptions
> 
> -- 
> You received this bug notification because you are a bug assignee.
> https://bugs.launchpad.net/bugs/1218842
> 
> Title:
>  STDHEP files larger than 4GB are corrupted
> 
> Status in The MadGraph Matrix Element Generator version 5:
>  Confirmed
> 
> Bug description:
>  I've just tested several STDHEP files produced by MG+HERWIG6.
> 
>  I've tested 50MB, 3.3GB and 4.0GB files.
> 
>  The 50MB and 3.3GB files can be read without any problem.
> 
>  The 4.0GB file can't be read.
> 
>  In the 4.0GB file, already the 2nd block has a block ID number equal
>  2. Normally, it should be 4 (Event Header). The following blocks have
>  completely wrong block ID numbers. So, I'd say that it's corrupted
>  from the very beginning.
> 
>  In some cases, adding the following compilation flag helps:
> 
>  -D_FILE_OFFSET_BITS=64
> 
>  Normally, the STDHEP library and maybe the PYTHIA and HERWIG
>  interfaces should be compiled with this flag.
> 
>  If you can tell me where to put this flag, I can redo the test.
> 
> To manage notifications about this bug go to:
> https://bugs.launchpad.net/madgraph5/+bug/1218842/+subscriptions