Problem while working simulatenously with multiple hdf5 files in one program

Hi everybody,

it looks like I will have to stay for a little longer a hdf5 user and member of this mailing-list.

I was searching in the Internet, have not found any useful information.
I'm writing an multithreaded application under Linux and stacked already at the begin. I know hdf5 library is only multithreading-safe, but I'm not sure, if it has somethings to it.

So, there are two threads in my program. Every thread has to save continuously obtained data into one .h5 file, as succeeding datasets. The problem comes as soon I want to create the .h5 files. It looks like, the library is not able to work with two independent files in one program. When I'm trying to start the second thread, which should create the second .h5 file the console yield:

HDF5-DIAG: Error detected in HDF5 (1.8.11) thread 0:
  #000: H5F.c line 1500 in H5Fcreate(): unable to create file
    major: File accessibilty
    minor: Unable to open file
  #001: H5F.c line 1303 in H5F_open(): unable to truncate a file which is already open
    major: File accessibilty
    minor: Unable to open file

What is interesting, the first line of error message, such like this above, always mentions only "thread 0".

I stress, there are no problems while working with a one thread/file.

Have somebody any hint or information, which could be useful in this case?

best regards