Re: [gentoo-user] Suggestion for freenode

[Jigme Datse Yli-RAsku]

I like that.  Haven't got to even reaching the "dev in training" stage, but I'd 
like to have some place where I can ask general gentoo-dev questions.  I have a 
couple of projects which I'd like to get working with a simple "emerge". 

Well.  One which is essentially a single project (LedgerSMB) another which is 
much larger (Matrix chat protocol, and at least the software I am using myself 
(Synapse, Vector-Web, unplug currently)). 

Jigme Datse Yli-Rasku

On 2016-09-03 21:37, Raymond Jennings wrote:
> I think #gentoo-mentors should be filled by people willing to serve as
> mentors, and cater to devs in training who need a mentor ^^
>
> What do you guys think?

-- 
Jigme Datse Yli-Rasku
jigme.da...@datsemultimedia.com (Preferred address for new messages)
250-505-6117

Jigme Datse Yli-Rasku
PO Box 270
Rossland, BC V0G 1Y0
Canada

...
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[gentoo-user] Suggestion for freenode

[Raymond Jennings]

I think #gentoo-mentors should be filled by people willing to serve as
mentors, and cater to devs in training who need a mentor ^^

What do you guys think?

[gentoo-user] openvpn and ipp.txt

[Bill Kenworthy]

Hi all,
I have a home openvpn server that works fine except the annoying
behaviour that it doesnt "fix" a client with an IP address.  That is,
with multiple clients it keeps swapping/reissueing IP addresses around.


Openvpn is supposed to use the file ipp.txt to hold the address mapping
its issued so it can reuse it as needed.  The file is automanaged and I
am not editing it in any way.  Openvpn creates the file as root:root and
u+rw on startup but entries never appear in it and there are no errors
in the logs.

Is this a know behaviour/how can I fix it?

BillK

[gentoo-user] HeeksCAD & HeeksCNC under Gentoo, any experiences?

[Urs Schütz]

Hi

HeeksCAD [1] and HeeksCNC [2] are open-source, 3D manufacturing tools 
and surprisingly complete in their feature set (from CAD to G-Code 
generation). I would like to give them a try, and found a way to compile 
them.


What I did:
edit opencascade keywords: =sci-libs/opencascade-6.8.0 ~amd64
emerge opencascade

compile and install libarea:
cd /tmp
git clone https://github.com/Heeks/libarea.git
cd libarea/
mkdir build
cd build
cmake ..
make
sudo make install

compile and install HeeksCAD:
cd /tmp
git clone https://github.com/Heeks/heekscad.git
cd heekscad/
mkdir build
cd build
export LD_LIBRARY_PATH=/usr/lib64/opencascade-6.8.0/ros/lin/lib64
export CASROOT=/usr/lib64/opencascade-6.8.0/ros/lin
cmake ..
make && sudo make install

compile and install HeeksCNC:
cd /tmp
git clone https://github.com/Heeks/heekscnc.git
mkdir heekscnc/build
cd heekscnc/build
export LD_LIBRARY_PATH=/usr/lib64/opencascade-6.8.0/ros/lin/lib64
export CASROOT=/usr/lib64/opencascade-6.8.0/ros/lin
cmake ..
make
sudo make install

To run HeeksCAD:
export LD_LIBRARY_PATH=/usr/lib64/opencascade-6.8.0/ros/lin/lib64; heekscad

What do others think about this 3D CAD / CAM solution?  Has anybody 
experience with HeeksCAD in a real application situation?


Urs

[1] https://github.com/Heeks/heekscad
[2] https://github.com/Heeks/heekscnc

Re: [gentoo-user] [OT] Is it still advisable to partition a big hard drive?

[Mick]

On Saturday 03 Sep 2016 16:39:03 Stroller wrote:
> > On 2 Sep 2016, at 23:03, Mick  wrote:
> > 
> > … a potentially more effective defrag method irrespective of fs
> > (we're talking about spinning disks where this issue applies) i
> 
> I understood that fragmentation can also occur on flash-based disks.
> 
> Although the effect of it is not so noticeable, I understood that it still
> has one.
> 
> Stroller.

Yes, flash drives (unlike spinning drivers) are completely digital.  In 
addition, wear levelling algorithms invariably kick in and bits and bytes are 
sprayed all over the pages/modules of the memory chips.  So you could say they 
are fragmented by design.

-- 
Regards,
Mick

signature.asc
Description: This is a digitally signed message part.

[gentoo-user] Re: Shutter alternatives

[Kai Krakow]

Am Sat, 27 Aug 2016 06:14:15 +0200
schrieb meino.cra...@gmx.de:

> Hi,
> 
> besider shutterbug -- what alternatives are available for
> the program "shutter"?

If you are a KDE user you might want to try spectacle.

-- 
Regards,
Kai

Replies to list-only preferred.

Re: [gentoo-user] Re: [OT] Is it still advisable to partition a big hard drive?

[Dale]

Kai Krakow wrote:
> Am Fri, 2 Sep 2016 17:42:13 -0500
> schrieb Dale :
>
>> Mick wrote:
>>> On Thursday 01 Sep 2016 22:57:12 Kai Krakow wrote:
>>>  
 Regarding performance:

 I wish Linux had options to relocate files (not just defragment)
 back into logical groups for nearby access. Fragmentation is less
 of a problem, the bigger problem is data block dislocation over
 time due to updates. In Windows, there's the wonderful tool
 MyDefrag which does magic and puts your aging Windows installation
 back into a state of an almost fresh installation by relocating
 files to sane positions.

 Is there anything similar for Linux?  
>>> Dale will pop in soon to mention the defrag application he was
>>> running on reiserfs, but a potentially more effective defrag method
>>> irrespective of fs (we're talking about spinning disks where this
>>> issue applies) is tar off/tar on your data.  
>> Now someone is asking for me to post something.  ROFL 
>>
>> Script should be attached.  Be forewarned, I have not used this script
>> in ages.  I have no clue if it works or not or if it will totally
>> screw up anything and everything.  I would recommend trying it on
>> something that doesn't matter or maybe a directory full of copied
>> files to be sure.  If it hoses your system, it's not my script and
>> you been warned. I'm not even sure where I got it from.  Might be the
>> forums but could be anywhere. 
>>
>> By the way, I switched to ext4 and it has a defrag command of its
>> own. Just man e4defrag for details, assuming you have the ext
>> utilities package installed.  That would be sys-fs/e2fsprogs by the
>> way.  I *think* it works on ext3 as well but not sure.  Everything
>> here is ext4 except /boot which is ext2. 
>>
>> I guess this is the benefit of large hard drives.  I don't have to
>> delete stuff even if I don't use it for a long time.  lol 
>>
>> Y'all have fun. 
> Well, this is not exactly what I was asking for. I think defragmenting
> files is really not that important as long as the fragments have some
> sane minimum sizes. I think something like contiguous chunks of 4 MB
> are enough for performance, SuSE seems to suggest 32 MB when you are
> looking at their btrfs maintenance script (it doesn't consider extents
> of more than 32MB for defragmentation).
>
> Much more important is to have executables, libs and data files nearby
> that are typically loaded at same time. The preload application
> (adaptive preload daemon) already does the right analysis by recording
> which files are needed and uses markov chains to predict which files
> you are going to need next to preload them into the page cache. I think,
> this data could also be used to rearrange files into better on-disk
> locations. Also, I think exploiting the page cache for this may not
> always be the best idea because in the end you may not need this data
> and it will push other important data out of cache.
>
> I think there's e4rat which already rearranges boot-related files to
> the start of the disk but it's ext[34] only. I think this technology
> could be developed further by clustering files needed by applications
> you start together.
>

All that sounds good but I don't know of any such tool to do that.  Some
people wanted a way to defrag things so someone wrote the script I
posted.  It worked back then but to be honest, I don't think defragging
is even really needed on Linux and any reasonably modern file system,
excluding the windozish ones that Linux can access like fat etc. 
Whenever I use such a tool or run some tool that shows fragmentation, it
is either none existent or so small that it doesn't matter.  Then there
is always those files that because of size, will always be fragmented. 

I guess no matter how fast hard drives get, someone will always want to
squeeze out just a little tiny fraction of more speed.  ;-)

Dale

:-)  :-) 

Re: [gentoo-user] Re: [OT] Is it still advisable to partition a big hard drive?

[Dale]

J. Roeleveld wrote:
> On Friday, September 02, 2016 05:42:13 PM Dale wrote:
>> Mick wrote:
>>> On Thursday 01 Sep 2016 22:57:12 Kai Krakow wrote:
 Regarding performance:

 I wish Linux had options to relocate files (not just defragment) back
 into logical groups for nearby access. Fragmentation is less of a
 problem, the bigger problem is data block dislocation over time due to
 updates. In Windows, there's the wonderful tool MyDefrag which does
 magic and puts your aging Windows installation back into a state of an
 almost fresh installation by relocating files to sane positions.

 Is there anything similar for Linux?
>>> Dale will pop in soon to mention the defrag application he was running on
>>> reiserfs, but a potentially more effective defrag method irrespective of
>>> fs
>>> (we're talking about spinning disks where this issue applies) is tar
>>> off/tar on your data.
>> Now someone is asking for me to post something.  ROFL
>>
>> Script should be attached.  Be forewarned, I have not used this script
>> in ages.  I have no clue if it works or not or if it will totally screw
>> up anything and everything.  I would recommend trying it on something
>> that doesn't matter or maybe a directory full of copied files to be
>> sure.  If it hoses your system, it's not my script and you been warned.
>> I'm not even sure where I got it from.  Might be the forums but could be
>> anywhere.
>>
>> By the way, I switched to ext4 and it has a defrag command of its own.
>> Just man e4defrag for details, assuming you have the ext utilities
>> package installed.  That would be sys-fs/e2fsprogs by the way.  I
>> *think* it works on ext3 as well but not sure.  Everything here is ext4
>> except /boot which is ext2.
>>
>> I guess this is the benefit of large hard drives.  I don't have to
>> delete stuff even if I don't use it for a long time.  lol
>>
>> Y'all have fun.
> How does that script work?
> >From a quick look, it depends on some application called "filefrag".
> I can't seem to find that on my system.
>
> --
> Joost
>
>


As I said, it's not my script.  I just got it from somewhere.  I have no
idea if it works much less how it works.  Based on the time stamp, it's
at least 10 years old and no telling how old it was before I got it. 

Dale

:-)  :-) 

Re: [gentoo-user] [OT] Is it still advisable to partition a big hard drive?

[Stroller]

> On 2 Sep 2016, at 23:03, Mick  wrote:
> 
> … a potentially more effective defrag method irrespective of fs 
> (we're talking about spinning disks where this issue applies) i

I understood that fragmentation can also occur on flash-based disks.

Although the effect of it is not so noticeable, I understood that it still has 
one.

Stroller.

[gentoo-user] Re: [OT] -print0 but with 'locate'

[Kai Krakow]

Am Sat, 3 Sep 2016 11:52:46 +0200
schrieb meino.cra...@gmx.de:

> Hi,
> 
> I want to 'locate' a bunch of files and feed the output into 
> '| xargs md5sum'.
> Unfortunately some of them are infected with the "file name"-virus
> (space in the filename).
> With find there is the -print0 option which corresponds to '-0' of
> the xargs options. As of my knowledge, locate does not have such 
> a thing.
> I dont like the idea to 'find' (read: 'search again')all the files,
> which locate already knows...so
> Is there any trick/option/whatever to get the files with spaced
> filenames processed by md5sum in combination with 'locate'?

In that case try

$ locate ... | while read name; do md5sum "$name"; done

This works for results having one filename per line.

-- 
Regards,
Kai

Replies to list-only preferred.

Re: [gentoo-user] [OT] -print0 but with 'locate'

[Meino . Cramer]

Neil Bothwick  [16-09-03 13:20]:
> On Sat, 3 Sep 2016 11:52:46 +0200, meino.cra...@gmx.de wrote:
> 
> > I want to 'locate' a bunch of files and feed the output into 
> > '| xargs md5sum'.  
> > Unfortunately some of them are infected with the "file name"-virus
> > (space in the filename).
> > With find there is the -print0 option which corresponds to '-0' of
> > the xargs options. As of my knowledge, locate does not have such 
> > a thing.
> 
> it does
> 
> locate -0 blah | xargs md5sum -0
> 
> 
> -- 
> Neil Bothwick
> 
> I heard someone tried the monkeys-on-typewriters bit trying for the plays
> of W. Shakespeare but all they got was the collected works of Francis
> Bacon


...ok thanks. THATS is what I was looking for...

Re: [gentoo-user] [OT] -print0 but with 'locate'

[Alan Mackenzie]

Hello, Meino.

On Sat, Sep 03, 2016 at 11:52:46AM +0200, meino.cra...@gmx.de wrote:
> Hi,

> I want to 'locate' a bunch of files and feed the output into 
> '| xargs md5sum'.
> Unfortunatexly some of them are infected with the "file name"-virus
> (space in the filename).
> With find there is the -print0 option which corresponds to '-0' of
> the xargs options. As of my knowledge, locate does not have such 
> a thing.
> I dont like the idea to 'find' (read: 'search again')all the files,
> which locate already knows...so
> Is there any trick/option/whatever to get the files with spaced
> filenames processed by md5sum in combination with 'locate'?

I'm afraid I don't know `locate' at all (it isn't on my system), but
does it have something like `ls''s -1 option which prints out each
filename on a separate line?  In this case you could put quote marks
around each file name, for example like this:

locate  -1 . | sed "s/^.*$/\'&\'/" | xargs md5sum

> Thank you very much in advance for any help!
> Best regards
> Meino

-- 
Alan Mackenzie (Nuremberg, Germany).

Re: [gentoo-user] [OT] -print0 but with 'locate'

[Neil Bothwick]

On Sat, 3 Sep 2016 11:52:46 +0200, meino.cra...@gmx.de wrote:

> I want to 'locate' a bunch of files and feed the output into 
> '| xargs md5sum'.  
> Unfortunately some of them are infected with the "file name"-virus
> (space in the filename).
> With find there is the -print0 option which corresponds to '-0' of
> the xargs options. As of my knowledge, locate does not have such 
> a thing.

it does

locate -0 blah | xargs md5sum -0


-- 
Neil Bothwick

I heard someone tried the monkeys-on-typewriters bit trying for the plays
of W. Shakespeare but all they got was the collected works of Francis
Bacon


pgpDWGtzYkCws.pgp
Description: OpenPGP digital signature

Re: [gentoo-user] [OT] -print0 but with 'locate'

[Alan McKinnon]

On 03/09/2016 12:43, meino.cra...@gmx.de wrote:
> Joerg Schilling  [16-09-03 12:28]:
>>  wrote:
>>
>>> Hi,
>>>
>>> I want to 'locate' a bunch of files and feed the output into 
>>> '| xargs md5sum'.
>>> Unfortunately some of them are infected with the "file name"-virus
>>> (space in the filename).
>>> With find there is the -print0 option which corresponds to '-0' of
>>> the xargs options. As of my knowledge, locate does not have such 
>>> a thing.
>>
>> This is one of the reasons, why POSIX did not include -print0, as it would 
>> need 
>> to add new related options to an unknown amount of other programs.
>>
>> Another reason of curse is that "find . -exec cmd {} +" exists longer than 
>> GNU 
>> find and it's -print0. Execplus was added on 1989 by David Korn.
>>
>> Jörg
>>
>> -- 
>>  EMail:jo...@schily.net(home) Jörg Schilling D-13353 
>> Berlin
>>joerg.schill...@fokus.fraunhofer.de (work) Blog: 
>> http://schily.blogspot.com/
>>  URL:  http://cdrecord.org/private/ 
>> http://sourceforge.net/projects/schilytools/files/'
>>
> 
> 
> ...and how does it solve my problem?

In several ways.

locate may or may not be up to date as it runs on a cron.
find OTOH tells you what files you really have right now.

Your objection to find IMHO is not really valid. It doesn't read all the
files, it simply reads all the *directories* and grabs the dentries for
the files from there. As you intend using locate, all you need is the
names and so find has no need to touch any file inodes it finds at all.
[ -mtime can really slow things down, but you won't be doing that ]

Do it once and even if you repeat the find many times in succession, all
the data find needs is now in RAM so it's not much more expensive than
locate.

So with that in mind there's no reason to not use find, then you get all
the -print0 goodness that you *really* need.

The alternative is to struggle endlessly with bash quoting rules to get
quotes around your filenames and quote the arguments to md5sum. Or some
magic with awk (all of which is many many times more cpu work than your
objection to find)

So use find :-)


-- 
Alan McKinnon
alan.mckin...@gmail.com

Re: [gentoo-user] [OT] -print0 but with 'locate'

[Meino . Cramer]

Joerg Schilling  [16-09-03 12:28]:
>  wrote:
> 
> > Hi,
> >
> > I want to 'locate' a bunch of files and feed the output into 
> > '| xargs md5sum'.
> > Unfortunately some of them are infected with the "file name"-virus
> > (space in the filename).
> > With find there is the -print0 option which corresponds to '-0' of
> > the xargs options. As of my knowledge, locate does not have such 
> > a thing.
> 
> This is one of the reasons, why POSIX did not include -print0, as it would 
> need 
> to add new related options to an unknown amount of other programs.
> 
> Another reason of curse is that "find . -exec cmd {} +" exists longer than 
> GNU 
> find and it's -print0. Execplus was added on 1989 by David Korn.
> 
> Jörg
> 
> -- 
>  EMail:jo...@schily.net(home) Jörg Schilling D-13353 
> Berlin
>joerg.schill...@fokus.fraunhofer.de (work) Blog: 
> http://schily.blogspot.com/
>  URL:  http://cdrecord.org/private/ 
> http://sourceforge.net/projects/schilytools/files/'
> 


...and how does it solve my problem?

Re: [gentoo-user] [OT] -print0 but with 'locate'

[Joerg Schilling]

 wrote:

> Hi,
>
> I want to 'locate' a bunch of files and feed the output into 
> '| xargs md5sum'.
> Unfortunately some of them are infected with the "file name"-virus
> (space in the filename).
> With find there is the -print0 option which corresponds to '-0' of
> the xargs options. As of my knowledge, locate does not have such 
> a thing.

This is one of the reasons, why POSIX did not include -print0, as it would need 
to add new related options to an unknown amount of other programs.

Another reason of curse is that "find . -exec cmd {} +" exists longer than GNU 
find and it's -print0. Execplus was added on 1989 by David Korn.

Jörg

-- 
 EMail:jo...@schily.net(home) Jörg Schilling D-13353 Berlin
   joerg.schill...@fokus.fraunhofer.de (work) Blog: 
http://schily.blogspot.com/
 URL:  http://cdrecord.org/private/ 
http://sourceforge.net/projects/schilytools/files/'

[gentoo-user] Re: [OT] Is it still advisable to partition a big hard drive?

[Kai Krakow]

Am Fri, 2 Sep 2016 17:42:13 -0500
schrieb Dale :

> Mick wrote:
> > On Thursday 01 Sep 2016 22:57:12 Kai Krakow wrote:
> >  
> >> Regarding performance:
> >>
> >> I wish Linux had options to relocate files (not just defragment)
> >> back into logical groups for nearby access. Fragmentation is less
> >> of a problem, the bigger problem is data block dislocation over
> >> time due to updates. In Windows, there's the wonderful tool
> >> MyDefrag which does magic and puts your aging Windows installation
> >> back into a state of an almost fresh installation by relocating
> >> files to sane positions.
> >>
> >> Is there anything similar for Linux?  
> > Dale will pop in soon to mention the defrag application he was
> > running on reiserfs, but a potentially more effective defrag method
> > irrespective of fs (we're talking about spinning disks where this
> > issue applies) is tar off/tar on your data.  
> 
> Now someone is asking for me to post something.  ROFL 
> 
> Script should be attached.  Be forewarned, I have not used this script
> in ages.  I have no clue if it works or not or if it will totally
> screw up anything and everything.  I would recommend trying it on
> something that doesn't matter or maybe a directory full of copied
> files to be sure.  If it hoses your system, it's not my script and
> you been warned. I'm not even sure where I got it from.  Might be the
> forums but could be anywhere. 
> 
> By the way, I switched to ext4 and it has a defrag command of its
> own. Just man e4defrag for details, assuming you have the ext
> utilities package installed.  That would be sys-fs/e2fsprogs by the
> way.  I *think* it works on ext3 as well but not sure.  Everything
> here is ext4 except /boot which is ext2. 
> 
> I guess this is the benefit of large hard drives.  I don't have to
> delete stuff even if I don't use it for a long time.  lol 
> 
> Y'all have fun. 

Well, this is not exactly what I was asking for. I think defragmenting
files is really not that important as long as the fragments have some
sane minimum sizes. I think something like contiguous chunks of 4 MB
are enough for performance, SuSE seems to suggest 32 MB when you are
looking at their btrfs maintenance script (it doesn't consider extents
of more than 32MB for defragmentation).

Much more important is to have executables, libs and data files nearby
that are typically loaded at same time. The preload application
(adaptive preload daemon) already does the right analysis by recording
which files are needed and uses markov chains to predict which files
you are going to need next to preload them into the page cache. I think,
this data could also be used to rearrange files into better on-disk
locations. Also, I think exploiting the page cache for this may not
always be the best idea because in the end you may not need this data
and it will push other important data out of cache.

I think there's e4rat which already rearranges boot-related files to
the start of the disk but it's ext[34] only. I think this technology
could be developed further by clustering files needed by applications
you start together.

-- 
Regards,
Kai

Replies to list-only preferred.

[gentoo-user] [OT] -print0 but with 'locate'

[Meino . Cramer]

Hi,

I want to 'locate' a bunch of files and feed the output into 
'| xargs md5sum'.
Unfortunately some of them are infected with the "file name"-virus
(space in the filename).
With find there is the -print0 option which corresponds to '-0' of
the xargs options. As of my knowledge, locate does not have such 
a thing.
I dont like the idea to 'find' (read: 'search again')all the files,
which locate already knows...so
Is there any trick/option/whatever to get the files with spaced
filenames processed by md5sum in combination with 'locate'?

Thank you very much in advance for any help!
Best regards
Meino

Re: [gentoo-user] Re: [OT] Is it still advisable to partition a big hard drive?

[J. Roeleveld]

On Friday, September 02, 2016 05:42:13 PM Dale wrote:
> Mick wrote:
> > On Thursday 01 Sep 2016 22:57:12 Kai Krakow wrote:
> >> Regarding performance:
> >> 
> >> I wish Linux had options to relocate files (not just defragment) back
> >> into logical groups for nearby access. Fragmentation is less of a
> >> problem, the bigger problem is data block dislocation over time due to
> >> updates. In Windows, there's the wonderful tool MyDefrag which does
> >> magic and puts your aging Windows installation back into a state of an
> >> almost fresh installation by relocating files to sane positions.
> >> 
> >> Is there anything similar for Linux?
> > 
> > Dale will pop in soon to mention the defrag application he was running on
> > reiserfs, but a potentially more effective defrag method irrespective of
> > fs
> > (we're talking about spinning disks where this issue applies) is tar
> > off/tar on your data.
> 
> Now someone is asking for me to post something.  ROFL
> 
> Script should be attached.  Be forewarned, I have not used this script
> in ages.  I have no clue if it works or not or if it will totally screw
> up anything and everything.  I would recommend trying it on something
> that doesn't matter or maybe a directory full of copied files to be
> sure.  If it hoses your system, it's not my script and you been warned.
> I'm not even sure where I got it from.  Might be the forums but could be
> anywhere.
> 
> By the way, I switched to ext4 and it has a defrag command of its own.
> Just man e4defrag for details, assuming you have the ext utilities
> package installed.  That would be sys-fs/e2fsprogs by the way.  I
> *think* it works on ext3 as well but not sure.  Everything here is ext4
> except /boot which is ext2.
> 
> I guess this is the benefit of large hard drives.  I don't have to
> delete stuff even if I don't use it for a long time.  lol
> 
> Y'all have fun.

How does that script work?
>From a quick look, it depends on some application called "filefrag".
I can't seem to find that on my system.

--
Joost

Re: [gentoo-user] Re: guvcview update produces an executable with missing lib...

[Meino . Cramer]

Kai Krakow  [16-09-02 03:52]:
> Am Tue, 30 Aug 2016 03:55:32 +0200
> schrieb meino.cra...@gmx.de:
> 
> > Daniel Frey  [16-08-30 03:48]:
> > > On 08/29/2016 11:11 AM, waltd...@waltdnes.org wrote:  
> > > > On Mon, Aug 29, 2016 at 06:29:50PM +0200, meino.cra...@gmx.de
> > > > wrote  
> >  [...]  
> >  [...]  
> >  [...]  
> > > > 
> > > >   The first suggestion in a case like this is to run
> > > > revdep-rebuild.  As a matter of fact, it probably wouldn't hurt
> > > > to run revdep-rebuild after every update.
> > > >   
> > > 
> > > Yes, I do. Portage occasionally misses a rebuild. It's a lot better
> > > now at catching them but it still misses them.
> > > 
> > > 
> > > 
> > > Dan
> > >   
> > 
> > Ok, we now know that depclean and redep rebuild are needed after each
> > update. It is someting, which I put together into one script which 
> > I run after each update.
> > 
> > And we know that portage seems to be guilty. And that it should not be
> > guilty. And that it does better in this cases.
> > 
> > One thing remains:
> > How can I get that guvcview up and running?
> 
> Try "emerge -1a @preserved-rebuild". It should catch preserved libs
> that revdep-rebuild cannot see at missing but doesn't scan neither
> because it doesn't consider them as part of the installed files.
> 
> Usually, after rebuilding everything to new metadata, you no longer use
> revdep-rebuild because the preserved-libs feature renders it mostly
> useless. Instead, @preserved-rebuild jumps in to rebuild and cleanup.
> 
> You may, however, catch a situation where the configure phase detects
> the new version of a lib but the linker phase uses the preserved lib of
> an older version of a dependent package. I'd consider this a bug of the
> ebuild or the package's build system usually. The way out here is do
> forcefully uninstall the package with the "broken" preserved lib, then
> reinstall what is not working.
> 
> It'd try this:
> 
> # Try to unmerge the package that portage thinks the file belongs to:
> $ emerge -Ca /usr/lib/libgviewv4l2core-1.0.so.1
> (or whereever this file should be, you can use pfl for finding out)
> 
> # rebuild binary broken packages now (we used -C, not -c)
> $ revdep-rebuild
> 
> # rebuild packages using preserved libs
> $ emerge -1a @preserved-rebuild
> 
> # rebuild your package now, it should now link to the correct lib
> $ emerge -1a guvcview
> 
> If that still doesn't help, try "qcheck -BHTP" to find packages with
> missing files. Rebuild those:
> 
> $ emerge -1a $(qcheck -BHTP)
> 
> If that also doesn't help, pretend that no dependencies are installed -
> this may rebuild A LOT of packages:
> 
> $ emerge -1e guvcview
> 
> -- 
> Regards,
> Kai
> 
> Replies to list-only preferred.
> 
> 

Hi Kai,

thank you very much for your useful help!!! :) 8)

This procedure finally fixed that problem.
I saved your posting to my "HowTo"s... :)

Have a nice weekend!
Best regards,
Meino