How to read/write one serial port device(like /dev/ttyUSB0) on Linux?

[zhengfish]

    Hi, Libuver,
        I want to read/write one serial port device(like /dev/ttyUSB0) on Linux.
        What's the handle type I can use?
        Or How can I setup the I/O context?

    Thx!


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[booch]

You can read/write to a usb device by simply using open/read/write system commands.

Try using a uv_fs_t with uv_fs_open/uv_fs_read/uv_fs_write functions.

These functions will simply communicate bytes of data which is what I think you're looking for.

MY

[Saúl Ibarra Corretgé]

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On 03/11/2014 06:21 PM, booch wrote:
> You can read/write to a usb device by simply using open/read/write
> system commands.
>
> Try using a uv_fs_t with uv_fs_open/uv_fs_read/uv_fs_write
> functions.
>
> These functions will simply communicate bytes of data which is what
> I think you're looking for.
>

The problem with that is that the fs operations run in the thread
pool. So, if you perform 4 uv_fs_read operations and the read()
syscall blocks, the entire thread pool is blocked, that means you
cannot run any other operations that require it, like uv_fd_*,
uv_queue_work, uv_getaddrinfo.

You could try to use a tty or pipe handle. Note that if you use
uv_pipe_open you'll need to set the fd to be non-blocking first.


Cheers,

- --
Saúl Ibarra Corretgé
bettercallsaghul.com

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