[Xcb] [EXTERNAL] - Attempt at writing a tutorial

[Lucas]

I believe that I found the rest of the answers for everything except for 
what the flag XCB_REQUEST_RAW does:

XCB_REQUEST_CHECKED (tells the server to provide the error, if any, 
inside a/reply/to a given request), XCB_REQUEST_DISCARD_REPLY (tells X 
to discard the reply, if any, to a given request), and 
XCB_REQUEST_REPLY_FDS (tells the server to include the number of socket 
file descriptors inside the reply to a given request,this appears to be 
for internal usage only 
<https://gitlab.freedesktop.org/xorg/lib/libxcb/-/blob/master/src/xcb_in.c#L246>). 
Member of the struct xcb_unmap_window_request_t pad0 may store the 
number of socket file descriptors depending on the request.


On 11/02/2021 14:58, Lucas Augusto Valentim Dantas wrote:
> Thank you very much! I will ruminate more on this and read on error 
> handling and events until I can write something intelligible about this.
> Meanwhile I would like to point out that the struct I was talking 
> about has the following members: major_opcode, pad0 (no idea what this 
> is nor how it is used), length (length of the request?), and window (I 
> kknow this is supposed to reference the window that is supposed to be 
> unmapped).
>
> https://xcb.freedesktop.org/manual/structxcb__unmap__window__request__t.html
> It also appears here 
> https://refspecs.linuxfoundation.org/LSB_5.0.0/LSB-Desktop-generic/LSB-Desktop-generic/libxcb-ddefs.html
>
> ------------------------------------------------------------------------
> *De:* Uli Schlachter <psychon at znc.in>
> *Enviado:* quinta-feira, 11 de fevereiro de 2021 14:37
> *Para:* Lucas Augusto Valentim Dantas <lucasvalentim at outlook.com.br>; 
> xcb at lists.freedesktop.org <xcb at lists.freedesktop.org>
> *Assunto:* Re: [Xcb] [EXTERNAL] - Attempt at writing a tutorial
> Hi,
>
> checked vs unchecked requests are explained here (under the heading of
> the same name):
>
> https://www.systutorials.com/docs/linux/man/3-xcb-requests/
>
> The short version is: This only makes a difference for X11 error
> handling. With unchecked requests, any errors show up as events in e.g.
> xcb_wait_for_event(). With checked requests, errors are provided when
> getting the reply (or calling xcb_check_request()).
>
> Cheers,
> Uli
>
> Am 11.02.21 um 18:28 schrieb Lucas Augusto Valentim Dantas:
> > I found those values by looking into the source code, probably 
> libxcb's, since they are passed to the second argument of the function 
> xcb_send_request(), as can be seen here (although the "sequence" 
> argument is gone already): 
> https://xcb.freedesktop.org/ProtocolExtensionApi/#index3h2 but that 
> page doesn't explain what they do.
> > My goal with this tutorial is to provide enough for the reader to 
> understand the X documentation so he is able to "navigate" on his own, 
> that is what I am trying to do myself.
> > ________________________________
> > De: Peter Harris <pharris at opentext.com>
> > Enviado: quinta-feira, 11 de fevereiro de 2021 14:15
> > Para: Lucas <lucasvalentim at outlook.com.br>; 
> xcb at lists.freedesktop.org <xcb at lists.freedesktop.org>
> > Assunto: RE: [EXTERNAL] - [Xcb] Attempt at writing a tutorial
> >
> > On 2021-02-10 Lucas wrote:
> >> I am writing a XCB tutorial as an exercise, so far, this is what I
> >> have https://biteiro.ga/xcb.html
> >>
> >> There are a few things I couldn't find details yet, such as what does
> >> the flags XCB_REQUEST_CHECKED, XCB_REQUEST_RAW,
> >> XCB_REQUEST_DISCARD_REPLY, and XCB_REQUEST_REPLY_FDS do?
> >
> > Those values are for internal use by libxcb (and/or xlib), and are 
> not intended to be used by a normal user of libxcb.
> >
> > Who is your tutorial intended for? Showing the inner workings is 
> more of a "deep documentation" thing than a "tutorial" thing.
> >
> >> Are there any
> >> explanations on the members of the struct xcb_unmap_window_request_t?
> >
> > libxcb is a thin wrapper around the X11 protocol. As such, the 
> documentation for those fields can be found at:
> >
> > 
> https://www.x.org/releases/X11R7.7/doc/xproto/x11protocol.html#request_format
> >
> > 
> https://www.x.org/releases/X11R7.7/doc/xproto/x11protocol.html#requests:UnmapWindow
> >
> > Peter Harris
> >
> >
> > _______________________________________________
> > Xcb mailing list
> > Xcb at lists.freedesktop.org
> > https://lists.freedesktop.org/mailman/listinfo/xcb
> >
>
>
> -- 
> <alanc> I think someone had a Xprint version of glxgears at one point,
>     but benchmarking how many GL pages you can print per second
>     was deemed too silly to merge
>
> _______________________________________________
> Xcb mailing list
> Xcb at lists.freedesktop.org
> https://lists.freedesktop.org/mailman/listinfo/xcb
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <https://lists.freedesktop.org/archives/xcb/attachments/20210211/a2e0c2c4/attachment.htm>