How to use strings in kernel functions or device functions

Accelerated Computing GPU-Accelerated Libraries
#1

Hi,
I need to use strings in kernel functions but whenever I use it I get the error that host function cannot be called in device code.
I searched about it and found out that as std::string is not primitive data type in c++ it is not allowed to be processed in kernels.
I need to use strings and their functions.
Can anyone please guide me about it ?
any sample code and suggestion would be appreciated.
I have heard about thrust but could not figure out how to use strings in thrust.

#2

That’s correct, std::string is not usable in CUDA device code.

Typical advice would be to handle things as C-style arrays of char

There are various examples on the internet, here are a few:

https://stackoverflow.com/questions/23130728/how-to-pass-string-matrix-to-cuda-kernel-from-c/23137136#23137136

https://stackoverflow.com/questions/34700999/cuda-passing-char-to-kernel/34712905#34712905

https://stackoverflow.com/questions/34326348/how-to-use-thrust-to-implement-reduce-by-key-when-keys-are-strings-or-char-array/34327062#34327062

https://stackoverflow.com/questions/20201335/add-char-arrays-in-cuda/20201511#20201511

The last one gives examples of how you could do strcpy, strcat, and strcmp

With perhaps a bit more time spent on integration, you could investigate use of the custrings library:

https://github.com/rapidsai/custrings

#3

Thank you very much @Robert_Crovella. Much appreciated