[mort96]

Wait, is that wrong? I always call fread as:

    fread(data, 1, sizeof(buffer), f);

with the rationale that I'm interested in reading sizeof(buffer) individual bytes. The buffer size is incidental, not the size of the items I'm trying to read from the file; "read one item whose size is sizeof(buffer)" seems semantically wrong.

Is this just the case of Windows having a bad stdlib fread implementation 15 years ago or is my thinking here actually wrong?

[chadgpt3]

It's not wrong. Guy just wrote a bad implementation of fread and blamed everyone else.

[DarkUranium]

He didn't write it.

The C runtime authors did (presumably Microsoft, if it's MSVCRT).

He's hooking into ReadFile, a layer below the stdlib. By the time it reaches the hook, it's already split.

[projektfu]

fread should be buffered, but different values may cause buffering at different rates. Perhaps it didn't generate 65535 calls to ReadFile but it generated 16 or 64.