The effect of the third parameter of uv_fs_write

[zhangwinning]

when I saw libuv book , there is a example about the fs.

_uv_fswrite function I understood some it, while I don't know the third params effect.

uv_fs_write(uv_default_loop(), &write_req, 1, &iov, 1, -1, on_write);

when I dig the doc，I find it is uv_file type，I don't know meaning it .

when I change the third params 1 to 2, the output is not change. when I write 3. the output is null.

[bnoordhuis]

It's the file descriptor. 1 and 2 are stdout and stderr respectively.

[zhangwinning]

@bnoordhuis thanks, I got it.