* why "PREFERRED_PROVIDER_udev" and not "PREFERRED_PROVIDER_virtual/udev"?
@ 2021-08-30 7:52 Robert P. J. Day
2021-08-30 16:09 ` [OE-core] " Khem Raj
2021-08-31 9:23 ` Richard Purdie
0 siblings, 2 replies; 6+ messages in thread
From: Robert P. J. Day @ 2021-08-30 7:52 UTC (permalink / raw)
To: OE Core mailing list
i was going to extend section 3.3.17, "Using Virtual Providers",
with an intro example using "udev" until i realized that that example
doesn't use the "virtual/" notation. so ... why not? is there some
distinction between other components that use the "virtual/" prefix,
but a reason that one does not specify:
PROVIDES = "virtual/udev"
rather than just:
PROVIDES = "udev"
and then use the corresponding PREFERRED_PROVIDER_virtual/udev
notation?
rday
^ permalink raw reply [flat|nested] 6+ messages in thread
* Re: [OE-core] why "PREFERRED_PROVIDER_udev" and not "PREFERRED_PROVIDER_virtual/udev"?
2021-08-30 7:52 why "PREFERRED_PROVIDER_udev" and not "PREFERRED_PROVIDER_virtual/udev"? Robert P. J. Day
@ 2021-08-30 16:09 ` Khem Raj
2021-08-31 8:27 ` Robert P. J. Day
2021-08-31 9:23 ` Richard Purdie
1 sibling, 1 reply; 6+ messages in thread
From: Khem Raj @ 2021-08-30 16:09 UTC (permalink / raw)
To: Robert P. J. Day; +Cc: OE Core mailing list
On Mon, Aug 30, 2021 at 12:52 AM Robert P. J. Day <rpjday@crashcourse.ca> wrote:
>
>
> i was going to extend section 3.3.17, "Using Virtual Providers",
> with an intro example using "udev" until i realized that that example
> doesn't use the "virtual/" notation. so ... why not? is there some
> distinction between other components that use the "virtual/" prefix,
> but a reason that one does not specify:
>
> PROVIDES = "virtual/udev"
>
> rather than just:
>
> PROVIDES = "udev"
>
> and then use the corresponding PREFERRED_PROVIDER_virtual/udev
> notation?
we also have VIRTUAL-RUNTIME_dev_manager which spans across systemd to mdev
so I guess we could but perhaps we already have this functionality
>
> rday
>
>
>
^ permalink raw reply [flat|nested] 6+ messages in thread
* Re: [OE-core] why "PREFERRED_PROVIDER_udev" and not "PREFERRED_PROVIDER_virtual/udev"?
2021-08-30 16:09 ` [OE-core] " Khem Raj
@ 2021-08-31 8:27 ` Robert P. J. Day
2021-08-31 9:24 ` Richard Purdie
0 siblings, 1 reply; 6+ messages in thread
From: Robert P. J. Day @ 2021-08-31 8:27 UTC (permalink / raw)
To: Khem Raj; +Cc: OE Core mailing list
On Mon, 30 Aug 2021, Khem Raj wrote:
> On Mon, Aug 30, 2021 at 12:52 AM Robert P. J. Day <rpjday@crashcourse.ca> wrote:
> >
> >
> > i was going to extend section 3.3.17, "Using Virtual Providers",
> > with an intro example using "udev" until i realized that that example
> > doesn't use the "virtual/" notation. so ... why not? is there some
> > distinction between other components that use the "virtual/" prefix,
> > but a reason that one does not specify:
> >
> > PROVIDES = "virtual/udev"
> >
> > rather than just:
> >
> > PROVIDES = "udev"
> >
> > and then use the corresponding PREFERRED_PROVIDER_virtual/udev
> > notation?
>
> we also have VIRTUAL-RUNTIME_dev_manager which spans across systemd to mdev
> so I guess we could but perhaps we already have this functionality
a followup, perhaps silly question -- is there anything special
about the "virtual/" prefix in the sense of being a provider? i mean,
other than being more aesthetically obvious?
rday
^ permalink raw reply [flat|nested] 6+ messages in thread
* Re: [OE-core] why "PREFERRED_PROVIDER_udev" and not "PREFERRED_PROVIDER_virtual/udev"?
2021-08-31 8:27 ` Robert P. J. Day
@ 2021-08-31 9:24 ` Richard Purdie
0 siblings, 0 replies; 6+ messages in thread
From: Richard Purdie @ 2021-08-31 9:24 UTC (permalink / raw)
To: Robert P. J. Day, Khem Raj; +Cc: OE Core mailing list
On Tue, 2021-08-31 at 04:27 -0400, Robert P. J. Day wrote:
> On Mon, 30 Aug 2021, Khem Raj wrote:
>
> > On Mon, Aug 30, 2021 at 12:52 AM Robert P. J. Day <rpjday@crashcourse.ca> wrote:
> > >
> > >
> > > i was going to extend section 3.3.17, "Using Virtual Providers",
> > > with an intro example using "udev" until i realized that that example
> > > doesn't use the "virtual/" notation. so ... why not? is there some
> > > distinction between other components that use the "virtual/" prefix,
> > > but a reason that one does not specify:
> > >
> > > PROVIDES = "virtual/udev"
> > >
> > > rather than just:
> > >
> > > PROVIDES = "udev"
> > >
> > > and then use the corresponding PREFERRED_PROVIDER_virtual/udev
> > > notation?
> >
> > we also have VIRTUAL-RUNTIME_dev_manager which spans across systemd to mdev
> > so I guess we could but perhaps we already have this functionality
>
> a followup, perhaps silly question -- is there anything special
> about the "virtual/" prefix in the sense of being a provider? i mean,
> other than being more aesthetically obvious?
Not really, it just signifies particular groups like the libc example I mention
in another mail.
Cheers,
Richard
^ permalink raw reply [flat|nested] 6+ messages in thread
* Re: [OE-core] why "PREFERRED_PROVIDER_udev" and not "PREFERRED_PROVIDER_virtual/udev"?
2021-08-30 7:52 why "PREFERRED_PROVIDER_udev" and not "PREFERRED_PROVIDER_virtual/udev"? Robert P. J. Day
2021-08-30 16:09 ` [OE-core] " Khem Raj
@ 2021-08-31 9:23 ` Richard Purdie
1 sibling, 0 replies; 6+ messages in thread
From: Richard Purdie @ 2021-08-31 9:23 UTC (permalink / raw)
To: Robert P. J. Day, OE Core mailing list
On Mon, 2021-08-30 at 03:52 -0400, Robert P. J. Day wrote:
> i was going to extend section 3.3.17, "Using Virtual Providers",
> with an intro example using "udev" until i realized that that example
> doesn't use the "virtual/" notation. so ... why not? is there some
> distinction between other components that use the "virtual/" prefix,
> but a reason that one does not specify:
>
> PROVIDES = "virtual/udev"
>
> rather than just:
>
> PROVIDES = "udev"
>
> and then use the corresponding PREFERRED_PROVIDER_virtual/udev
> notation?
The "virtual/" namespace is just a way of namespacing some key dependencies
outside of the direct recipe namespace.
virtual/libc is a better example and there are a few toolchain related ones.
There are several different libc implementations and virtual/libc just says you
want one without being specific.
Cheers,
Richard
^ permalink raw reply [flat|nested] 6+ messages in thread
[parent not found: <16A0063E8A02B067.22970@lists.openembedded.org>]
* Re: [OE-core] why "PREFERRED_PROVIDER_udev" and not "PREFERRED_PROVIDER_virtual/udev"?
[not found] <16A0063E8A02B067.22970@lists.openembedded.org>
@ 2021-08-30 8:11 ` Robert P. J. Day
0 siblings, 0 replies; 6+ messages in thread
From: Robert P. J. Day @ 2021-08-30 8:11 UTC (permalink / raw)
To: OE Core mailing list
On Mon, 30 Aug 2021, Robert P. J. Day wrote:
> i was going to extend section 3.3.17, "Using Virtual Providers",
> with an intro example using "udev" until i realized that that
> example doesn't use the "virtual/" notation. so ... why not? is
> there some distinction between other components that use the
> "virtual/" prefix, but a reason that one does not specify:
>
> PROVIDES = "virtual/udev"
>
> rather than just:
>
> PROVIDES = "udev"
>
> and then use the corresponding PREFERRED_PROVIDER_virtual/udev
> notation?
just to make sure folks understand what i'm getting at, the section:
https://docs.yoctoproject.org/dev-manual/common-tasks.html#using-virtual-providers
opens with, "Prior to a build, if you know that several different
recipes provide the same functionality, you can use a virtual provider
(i.e. virtual/*) as a placeholder for the actual provider."
except there are cases where several different recipes provide the
same functionality that *don't* incorporate the "virtual/" notation,
so which ones merit that and which ones don't? (i mentioned "udev"
being provided by both "eudev" and "systemd", for which i wrote an
utterly brilliant explanation that i now realize isn't appropriate for
that section.)
in the simpler cases, you have recipes that have a new name that
can now be used in place of the old, such that "stress-ng" provides
"stress", so you don't have to mess with all your old images and
packagegroups. and in situations like that, the "virtual/" notation
would seem out of place.
OTOH, well, virtual "kernel" and "bootloader" makes perfect sense as
they represent a more abstract idea. so ... thoughts? even though
"udev" does not use the "virtual/" notation, would it still fall under
the category of "virtual provider"? if not, how would one describe it?
rday
^ permalink raw reply [flat|nested] 6+ messages in thread
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2021-08-30 7:52 why "PREFERRED_PROVIDER_udev" and not "PREFERRED_PROVIDER_virtual/udev"? Robert P. J. Day
2021-08-30 16:09 ` [OE-core] " Khem Raj
2021-08-31 8:27 ` Robert P. J. Day
2021-08-31 9:24 ` Richard Purdie
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