[Gdal-dev] Threading and CSV files

[Frank Warmerdam]

On 12/22/05, Sheykhet, Rostic <rsheykhet at sanz.com> wrote:
> Hi All/Frank,
>
> I am trying to debug a SEGFAULT in gdal 1.3.1 on Linux with multiple
> threads accessing the same tiff file. Each thread creates its own
> DataSource.  Looks like what's happening is that multiple threads are
> trying to access the same data structure (CSV file table defined in
> cpl_csv.cpp) concurrently and are corrupting it.   The table variable is
> declared as CPL_THREADLOCAL, but CPL_THREADLOCAL is currently a blank
> #define statement.  Is there a way to bypass/mitigate this issue?

Rostic,

Good point.  I have commited changes to protect the
open csv file list in cpl_csv.c with a mutex.   Could
you try again with those changes in place?   I have
tried some fairly intensive multiple thread TIFF access
before, but didn't encounter this particular problem.

Best regards,

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