CreateItem returns bit-shifted PublishedFileId

[Zarkonnen]

I've encountered this issue running Steamworks.NET on Windows. It doesn't occur on Linux.

Reproduce

• Call SteamUGC.CreateItem
• Look at the resulting CreateItemResult_t

Expected

• m_eResult is k_EResultOK
• m_nPublishedFileId is the ID of the created item, eg 3430242989 for a test run I did.
• The workshop item is created at ID 3430242989

Observed

• m_eResult is k_EResultOK
• m_nPublishedFileId is a different number, eg 14732781458309514128 for the same test run.
• The workshop item is created at ID 3430242989

Upon closer inspection, (14732781458309514128 >> 32) == 3430242989.

Byte-by-byte, least significant byte first:

Expected:
173 90 117 204 0 0 0 0

Observed:
144 3 0 192 173 90 117 204

So the returned value is the expected value but shifted 32 bits to the left and with additional information inserted in the four lower bytes.

Using the observed file ID to then call SubmitItemUpdate causes a k_EResultFileNotFound error, whereas using the expected bit shifted ID works correctly.

This is on Release 2024.8.0.

[yaakov-h]

struct layout or padding problem, perhaps?

[Zarkonnen]

struct layout or padding problem, perhaps?

Looks like it, yes. I'm using the DLLs shipped with 2024.8.0, so I don't know why it's not aligned.