# Checklist
- [x] I have read the [contribution guidelines] (https://github.com/Azure/azure-iot-sdk-c/blob/main/.github/CONTRIBUTING.md).
- [ ] I added or modified the existing tests to cover the change (we do not allow our test coverage to go down).
- If this is a modification that impacts the behavior of a public API
- [ ] I edited the corresponding document in the `devdoc` folder and added or modified requirements.
- I submitted this PR against the correct branch:
- [x] This pull-request is submitted against the `main` branch.
- [x] I have merged the latest `main` branch prior to submission and re-merged as needed after I took any feedback.
- [x] I have squashed my changes into one with a clear description of the change.
# Reference/Link to the issue solved with this PR (if any)
# Description of the problem
When simulating errors during upload to blob, the response message back to IoT Hub was generated with incorrect response code. That's because the sprintf-like function expected the code as integer, but the code was passing a const char*.
Description of the solution
Change the default error code for u2b to integer.
**Note: unit tests were not modified because the STRING_construct_sprintf is mocked (abstracted) in iothub_client_ll_u2b_ut**
When simulating errors during upload to blob, the response message back to IoT Hub was generated with incorrect response code. That's because the sprintf-like function expected the code as integer, but the code was passing a const char*.
Description of the solution
Change the default error code for u2b to integer. **Note: unit tests were not modified because the STRING_construct_sprintf is mocked (abstracted) in iothub_client_ll_u2b_ut**