This is just returning the error upwards, as far as I can tell.

This is the pattern I usually see in actual Go codebases:

    infp, err := os.Open(infile)
    if err != nil {
        return err
    }
    defer infp.Close()
    outfp, err := os.Create(outfile)
    if err != nil {
        return err
    }
    defer outfp.Close()
    // ... do some stuff ...
    return outfp.Close()

Note that double-close is explicitly OK, this pattern just avoids losing the error.