How to save augmented data generated by BasePrefetchDataLayer

[peyer]

Issue summary

As the title, How can I save augmented data and label generated by using BasePrefetchDataLayer since it used InternalThread to create multi-process? I encounter crash when I used fwrite() func to save the data and label into binary file.

Steps to reproduce

Tried solutions

System configuration

• Operating system: Ubuntu 16.04
• Compiler: gcc
• CUDA version (if applicable): 9.0
• CUDNN version (if applicable): 7.0
• BLAS: openBLAS
• Python version (if using pycaffe): 2.7.12
• MATLAB version (if using matcaffe): R2015b

Issue checklist

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