w32-get-clipboard-data

w32-get-clipboard-data

[stephencoda]

For me, w32-get-clipboard-data
always returns null.

I was trying to understand why I couldn't use copy and paste in emacs so I followed the elisp to x-get-selection-value which calls w32-get-clipboard-data.

But I hit C source code bedrock here:

"""
w32-get-clipboard-data is a built-in function in `C source code'.

(w32-get-clipboard-data &optional IGNORED)

This gets the clipboard data in text format.

[back]
"""

Does anyone have any insights as to why this function doesn't appear to be working for me?

Kind regards,
Steve

Re: w32-get-clipboard-data

[Jason Rumney]

On Tuesday, 25 August 2015 18:44:07 UTC+8, Stephen Coda  wrote:
> For me, w32-get-clipboard-data
> always returns null.

w32-get-clipboard-data returns nil if Emacs owns the clipboard, so that the internal yank implementation will be used instead, as that will preserve text properties in addition to the raw text.

If you copy some text to the clipboard outside of Emacs, does w32-get-clipboard-data return the expected result then?  In what way is copy/paste not working for you in Emacs?

Re: w32-get-clipboard-data

[Stephen Coda]

On Tuesday, 25 August 2015 15:54:26 UTC+1, Jason Rumney  wrote:
> On Tuesday, 25 August 2015 18:44:07 UTC+8, Stephen Coda  wrote:
> > For me, w32-get-clipboard-data
> > always returns null.
> 
> w32-get-clipboard-data returns nil if Emacs owns the clipboard, so that the internal yank implementation will be used instead, as that will preserve text properties in addition to the raw text.
> 
> If you copy some text to the clipboard outside of Emacs, does w32-get-clipboard-data return the expected result then?  In what way is copy/paste not working for you in Emacs?

Hi Jason,
w32-get-clipboard-data does return nil. Copy and Paste work only inside of emacs, but if I copy text from another app, say notepad, I can't paste it into emacs.

Cheers,
Steve

Re: w32-get-clipboard-data

[Robert Thorpe]

stephencoda@googlemail.com writes:

> For me, w32-get-clipboard-data
> always returns null.

Have you tried emacs -Q and then the usual kill/yank keys?  I've never
known the clipboard to fail on MS Windows.

BR,
Robert Thorpe

Re: w32-get-clipboard-data

[Stephen Coda]

On Wednesday, 26 August 2015 00:57:46 UTC+1, Robert Thorpe  wrote:
> stephencoda@googlemail.com writes:
> 
> > For me, w32-get-clipboard-data
> > always returns null.
> 
> Have you tried emacs -Q and then the usual kill/yank keys?  I've never
> known the clipboard to fail on MS Windows.
> 
> BR,
> Robert Thorpe

Hi Robert,
emacs -Q doesn't seem to make any difference with regards to Pasting. I have a couple of different versions of emacs on my machine, including PCemacs that comes with swi-prolog, they all suffer from the same problem which makes it look like a windows issue to me, *until someone more knowledgeable than I has a better suggestion.

Cheers,
Steve

Re: w32-get-clipboard-data

[Robert Thorpe]

Stephen Coda <stephencoda@googlemail.com> writes:
...
> Hi Robert,
>
> emacs -Q doesn't seem to make any difference with regards to
> Pasting. I have a couple of different versions of emacs on my machine,
> including PCemacs that comes with swi-prolog, they all suffer from the
> same problem which makes it look like a windows issue to me, *until
> someone more knowledgeable than I has a better suggestion.

That's wierd.  Have you tried a different Windows machine?  For Windows
I think you can just copy the whole Emacs directory to the other
machine, then run addpm.exe.

I can't think of a Windows setting that would make this break.

BR,
Robert Thorpe

Re: w32-get-clipboard-data

[Stephen Coda]

It's only ever happened to me on this particular machine. Unfortunately I don't control how it is set up.

I ran addpm.exe to be sure. No change. :/

So currently I cut and paste stuff into notepad++ into a file I share with emacs. Then I can grab stuff from there while I'm in emacs to kill/yank. It works, but it's no way to live.

Kind regards,
Steve

On Sunday, 30 August 2015 21:58:50 UTC+1, Robert Thorpe  wrote:
> Stephen Coda <stephencoda@googlemail.com> writes:
> ...
> > Hi Robert,
> >
> > emacs -Q doesn't seem to make any difference with regards to
> > Pasting. I have a couple of different versions of emacs on my machine,
> > including PCemacs that comes with swi-prolog, they all suffer from the
> > same problem which makes it look like a windows issue to me, *until
> > someone more knowledgeable than I has a better suggestion.
> 
> That's wierd.  Have you tried a different Windows machine?  For Windows
> I think you can just copy the whole Emacs directory to the other
> machine, then run addpm.exe.
> 
> I can't think of a Windows setting that would make this break.
> 
> BR,
> Robert Thorpe

Re: w32-get-clipboard-data

[Eli Zaretskii]

> Date: Tue, 1 Sep 2015 01:21:45 -0700 (PDT)
> From: Stephen Coda <stephencoda@googlemail.com>
> 
> It's only ever happened to me on this particular machine. Unfortunately I don't control how it is set up.
> 
> I ran addpm.exe to be sure. No change. :/
> 
> So currently I cut and paste stuff into notepad++ into a file I share with emacs. Then I can grab stuff from there while I'm in emacs to kill/yank. It works, but it's no way to live.

Indeed.

After you copy into the clipboard from another application, can you
look with some clipboard viewing program and tell what formats are in
the clipboard?  Emacs understands only a small fraction of the
possible formats, so perhaps that system was configured to not use
those formats (e.g., for security reasons).

Re: w32-get-clipboard-data

[Random832]

Stephen Coda <stephencoda@googlemail.com> writes:

> It's only ever happened to me on this particular
> machine. Unfortunately I don't control how it is set up.

How *is* it set up? Is there anything installed/running that might be
doing unusual things with the clipboard (clipboard managers, monitoring
programs, remote desktop access [whether outgoing or incoming])?

It seems unusual though that pasting into other apps works if this is
the case. You can't copy *or* paste in Emacs?

Are you able to build a test C program to exercise
OpenClipboard, GetClipboardData(CF_UNICODETEXT), CloseClipboard and see
if they all function as expected independent of Emacs?

Re: w32-get-clipboard-data

[Stephen Coda]

On Wednesday, 2 September 2015 06:35:26 UTC+1, Random832  wrote:
> Stephen Coda <stephencoda@googlemail.com> writes:
> 
> > It's only ever happened to me on this particular
> > machine. Unfortunately I don't control how it is set up.
> 
> How *is* it set up? Is there anything installed/running that might be
> doing unusual things with the clipboard (clipboard managers, monitoring
> programs, remote desktop access [whether outgoing or incoming])?
> 
> It seems unusual though that pasting into other apps works if this is
> the case. You can't copy *or* paste in Emacs?
> 
> Are you able to build a test C program to exercise
> OpenClipboard, GetClipboardData(CF_UNICODETEXT), CloseClipboard and see
> if they all function as expected independent of Emacs?

Hi Random832,

It is set up by an admin:) 
I think it might well be a security issue, and that maybe websecure anywhere is responsible. But I don't have access to the settings and have submitted a ticket to get this looked into.

And just tried GetClipboardData, it is returning null....

Kind regards,
Steve

Re: w32-get-clipboard-data

[Random832]

Stephen Coda <stephencoda@googlemail.com> writes:

> On Wednesday, 2 September 2015 06:35:26 UTC+1, Random832  wrote:
> Hi Random832,
>
> It is set up by an admin:) 
> I think it might well be a security issue, and that maybe websecure
> anywhere is responsible. But I don't have access to the settings and
> have submitted a ticket to get this looked into.
>
> And just tried GetClipboardData, it is returning null....

What does OpenClipboard return? You have to have called it, and had it
return TRUE/1, before you're allowed to call GetClipboardData.

One thing I noticed looking over the Emacs code is that it bails out
immediately without any sort of retry dance if OpenClipboard fails - and
it *does* fail, rather than block, if some other app has the clipoard
open at the moment it is called. Are you *ever* able to paste into
Emacs? If this is intermittent, maybe there's some other app running
that just opens it very often and you keep colliding with it.

Re: w32-get-clipboard-data

[Stephen Coda]

On Thursday, 3 September 2015 02:35:29 UTC+1, Random832  wrote:
> Stephen Coda <stephencoda@googlemail.com> writes:
> 
> > On Wednesday, 2 September 2015 06:35:26 UTC+1, Random832  wrote:
> > Hi Random832,
> >
> > It is set up by an admin:) 
> > I think it might well be a security issue, and that maybe websecure
> > anywhere is responsible. But I don't have access to the settings and
> > have submitted a ticket to get this looked into.
> >
> > And just tried GetClipboardData, it is returning null....
> 
> What does OpenClipboard return? You have to have called it, and had it
> return TRUE/1, before you're allowed to call GetClipboardData.
> 
> One thing I noticed looking over the Emacs code is that it bails out
> immediately without any sort of retry dance if OpenClipboard fails - and
> it *does* fail, rather than block, if some other app has the clipoard
> open at the moment it is called. Are you *ever* able to paste into
> Emacs? If this is intermittent, maybe there's some other app running
> that just opens it very often and you keep colliding with it.

OpenCliboard returns true. 
I didn't think I could paste under any circs in emacs, but this morning discovered I can if chrome isn't open... So it does look like some sort of collision.

Kind regards,
Steve

Re: w32-get-clipboard-data

[Stephen Coda]

On Tuesday, 1 September 2015 15:41:04 UTC+1, Eli Zaretskii  wrote:
> > Date: Tue, 1 Sep 2015 01:21:45 -0700 (PDT)
> > From: Stephen Coda <stephencoda@googlemail.com>
> > 
> > It's only ever happened to me on this particular machine. Unfortunately I don't control how it is set up.
> > 
> > I ran addpm.exe to be sure. No change. :/
> > 
> > So currently I cut and paste stuff into notepad++ into a file I share with emacs. Then I can grab stuff from there while I'm in emacs to kill/yank. It works, but it's no way to live.
> 
> Indeed.
> 
> After you copy into the clipboard from another application, can you
> look with some clipboard viewing program and tell what formats are in
> the clipboard?  Emacs understands only a small fraction of the
> possible formats, so perhaps that system was configured to not use
> those formats (e.g., for security reasons).

Hi Eli,

I couldn't see anything weird in there format wise.
I'm suspecting a security issue.

Kind regards,
Steve

Re: w32-get-clipboard-data

[Eli Zaretskii]

> Date: Wed, 2 Sep 2015 07:01:16 -0700 (PDT)
> From: Stephen Coda <stephencoda@googlemail.com>
> 
> > After you copy into the clipboard from another application, can you
> > look with some clipboard viewing program and tell what formats are in
> > the clipboard?  Emacs understands only a small fraction of the
> > possible formats, so perhaps that system was configured to not use
> > those formats (e.g., for security reasons).
> 
> I couldn't see anything weird in there format wise.

Which format(s) do you see in the clipboard, and what tool did you use
to find that out?

Re: w32-get-clipboard-data

[Stephen Coda]

On Wednesday, 2 September 2015 15:46:57 UTC+1, Eli Zaretskii  wrote:
> > Date: Wed, 2 Sep 2015 07:01:16 -0700 (PDT)
> > From: Stephen Coda <stephencoda@googlemail.com>
> > 
> > > After you copy into the clipboard from another application, can you
> > > look with some clipboard viewing program and tell what formats are in
> > > the clipboard?  Emacs understands only a small fraction of the
> > > possible formats, so perhaps that system was configured to not use
> > > those formats (e.g., for security reasons).
> > 
> > I couldn't see anything weird in there format wise.
> 
> Which format(s) do you see in the clipboard, and what tool did you use
> to find that out?

EnumClipboardFormats(format) from the windows C++ library. 

But I must have been asleep because somehow I missed 49442, or C122 in hex which I couldn't find a define for.

It also looks as if I can paste when Chrome is not open.

Kind regards,
Steve

Re: w32-get-clipboard-data

[Stephen Coda]

On Thursday, 3 September 2015 10:07:42 UTC+1, Stephen Coda  wrote:
> On Wednesday, 2 September 2015 15:46:57 UTC+1, Eli Zaretskii  wrote:
> > > Date: Wed, 2 Sep 2015 07:01:16 -0700 (PDT)
> > > From: Stephen Coda <stephencoda@googlemail.com>
> > > 
> > > > After you copy into the clipboard from another application, can you
> > > > look with some clipboard viewing program and tell what formats are in
> > > > the clipboard?  Emacs understands only a small fraction of the
> > > > possible formats, so perhaps that system was configured to not use
> > > > those formats (e.g., for security reasons).
> > > 
> > > I couldn't see anything weird in there format wise.
> > 
> > Which format(s) do you see in the clipboard, and what tool did you use
> > to find that out?
> 
> EnumClipboardFormats(format) from the windows C++ library. 
> 
> But I must have been asleep because somehow I missed 49442, or C122 in hex which I couldn't find a define for.
> 
> It also looks as if I can paste when Chrome is not open.
> 
> Kind regards,
> Steve

Okay, I might not have missed it yesterday it might not have been there, I tried again today and got another new number 49161, which is some sort of IDataObject apparently.

Re: w32-get-clipboard-data

[Jason Rumney]

Extra formats should not cause an issue, as long as one or both of UNICODETEXT or TEXT are on the list of formats, Emacs will request those.

Re: w32-get-clipboard-data

[Stephen Coda]

On Thursday, 3 September 2015 15:22:40 UTC+1, Jason Rumney  wrote:
> Extra formats should not cause an issue, as long as one or both of UNICODETEXT or TEXT are on the list of formats, Emacs will request those.

Cheers,
Yes they were, it looks like this was all some sort of clipboard contention with chrome cause by security settings.

Kind regards,
Steve

Re: w32-get-clipboard-data

[Eli Zaretskii]

> Date: Thu, 3 Sep 2015 02:07:39 -0700 (PDT)
> From: Stephen Coda <stephencoda@googlemail.com>
> 
> It also looks as if I can paste when Chrome is not open.

I think that's the reason for the problem, right there.  I'm guessing
Chrome has some paste-blocking feature or some clipboard-related
feature which you need to customize or even turn off.  (Sorry, I don't
use Chrome, so I cannot give you more details.)

Re: w32-get-clipboard-data

[Robert Thorpe]

Eli Zaretskii <eliz@gnu.org> writes:
...
> I think that's the reason for the problem, right there.  I'm guessing
> Chrome has some paste-blocking feature or some clipboard-related
> feature which you need to customize or even turn off.  (Sorry, I don't
> use Chrome, so I cannot give you more details.)

Chrome is well used, it seems unlikely that Chrome would have a bug like
that.  But, some Chrome plugins are rarely used and badly maintained, they could have.

BR,
Robert Thorpe

Re: w32-get-clipboard-data

[Stephen Coda]

On Thursday, 3 September 2015 15:38:38 UTC+1, Eli Zaretskii  wrote:
> > Date: Thu, 3 Sep 2015 02:07:39 -0700 (PDT)
> > From: Stephen Coda <stephencoda@googlemail.com>
> > 
> > It also looks as if I can paste when Chrome is not open.
> 
> I think that's the reason for the problem, right there.  I'm guessing
> Chrome has some paste-blocking feature or some clipboard-related
> feature which you need to customize or even turn off.  (Sorry, I don't
> use Chrome, so I cannot give you more details.)

It required adding emacs.exe to a list of things that were allowed to use the clipboard while chrome was open. Since chrome is a connection to the internet and cutting and pasting from that place constitutes a potential security risk. I think that's the reason, our sys admin sorted the setting  for me. 

Kind regards,
Steve

Re: w32-get-clipboard-data

[Eli Zaretskii]

> Date: Fri, 4 Sep 2015 01:58:29 -0700 (PDT)
> From: Stephen Coda <stephencoda@googlemail.com>
> 
> On Thursday, 3 September 2015 15:38:38 UTC+1, Eli Zaretskii  wrote:
> > > Date: Thu, 3 Sep 2015 02:07:39 -0700 (PDT)
> > > From: Stephen Coda <stephencoda@googlemail.com>
> > > 
> > > It also looks as if I can paste when Chrome is not open.
> > 
> > I think that's the reason for the problem, right there.  I'm guessing
> > Chrome has some paste-blocking feature or some clipboard-related
> > feature which you need to customize or even turn off.  (Sorry, I don't
> > use Chrome, so I cannot give you more details.)
> 
> It required adding emacs.exe to a list of things that were allowed to use the clipboard while chrome was open. Since chrome is a connection to the internet and cutting and pasting from that place constitutes a potential security risk. I think that's the reason, our sys admin sorted the setting  for me. 

Thanks for letting us know.  Is it possible for you to tell more
details about how to add Emacs to that list?  I'd like to put the
problem and the solution into Emacs's PROBLEMS file.

Re: w32-get-clipboard-data

[Stephen Coda]

On Friday, 4 September 2015 10:12:25 UTC+1, Eli Zaretskii  wrote:
> > Date: Fri, 4 Sep 2015 01:58:29 -0700 (PDT)
> > From: Stephen Coda <stephencoda@googlemail.com>
> > 
> > On Thursday, 3 September 2015 15:38:38 UTC+1, Eli Zaretskii  wrote:
> > > > Date: Thu, 3 Sep 2015 02:07:39 -0700 (PDT)
> > > > From: Stephen Coda <stephencoda@googlemail.com>
> > > > 
> > > > It also looks as if I can paste when Chrome is not open.
> > > 
> > > I think that's the reason for the problem, right there.  I'm guessing
> > > Chrome has some paste-blocking feature or some clipboard-related
> > > feature which you need to customize or even turn off.  (Sorry, I don't
> > > use Chrome, so I cannot give you more details.)
> > 
> > It required adding emacs.exe to a list of things that were allowed to use the clipboard while chrome was open. Since chrome is a connection to the internet and cutting and pasting from that place constitutes a potential security risk. I think that's the reason, our sys admin sorted the setting  for me. 
> 
> Thanks for letting us know.  Is it possible for you to tell more
> details about how to add Emacs to that list?  I'd like to put the
> problem and the solution into Emacs's PROBLEMS file.

Yes no problem,
I think our admin had to do this for the emacs.exe:
" Simply open SecureAnywhere>click Identity & Privacy>click View/Edit Protected Applications>find your application and set it to Allow. "

Kind regards,
Steve

Re: w32-get-clipboard-data

[Ian Zimmerman]

On 2015-08-25 03:44 -0700, stephencoda@googlemail.com wrote:

> I was trying to understand why I couldn't use copy and paste in emacs
> so I followed the elisp to x-get-selection-value which calls
> w32-get-clipboard-data.

I never had a definite answer to this [1] Debian bug report which I
filed in 2002.  May be relevant or not.

[1]
https://lists.debian.org/debian-emacsen/2002/08/msg00008.html

-- 
Please *no* private copies of mailing list or newsgroup messages.
Rule 420: All persons more than eight miles high to leave the court.

Re: w32-get-clipboard-data

[Rusi]

On Wednesday, September 2, 2015 at 3:02:04 PM UTC+5:30, Ian Zimmerman wrote:
> On 2015-08-25 03:44 -0700, stephencoda wrote:
> 
> > I was trying to understand why I couldn't use copy and paste in emacs
> > so I followed the elisp to x-get-selection-value which calls
> > w32-get-clipboard-data.
> 
> I never had a definite answer to this [1] Debian bug report which I
> filed in 2002.  May be relevant or not.
> 
> [1]
> https://lists.debian.org/debian-emacsen/2002/08/msg00008.html

Well all I can say is its 2015 and I still see that...
probably more often than once a week.
[Probably not related to the OP as he is on windows]