I'm curious why only some of the returns from stransfer are checked for errors. The documentation doesn't say what return values the stransfer functions have except that it is integer.

There are a few masked ones that I missed, I was going to make a PR tomorrow for them. Almost all should be checked, there may be some that just can never error, but those should be pretty deep, e.g. in dtype_transfer.c.

@charris to be clear, the stransfer had no return value at all until recently. Right now the only valid return values are 0 and -1 for error. We could think about more complex schemes, such as returning the unprocessed number of items.

The function here actually is supposed to return the number of processed elements (as per documentation), but... That fact is not even used (I presume it was used in some initial version, or just done with potential improvement in mind).

There is some reason for doing that, but it is one of those things that is reaching my limit of playing it out without having a clear, simple, use.

The function here actually is supposed to return the number of processed elements

Probably copied from similar C library functions (read/write).

Thanks Sebastian.