Send Pharo-users mailing list submissions to
�� �� �� �� pharo-users@lists.pharo.org
To subscribe or unsubscribe via the World Wide Web, visit
�� �� �� �� http://lists.pharo.org/mailman/listinfo/pharo-users_lists.pharo.org
or, via email, send a message with subject or body 'help' to
�� �� �� �� pharo-users-request@lists.pharo.org
You can reach the person managing the list at
�� �� �� �� pharo-users-owner@lists.pharo.org
When replying, please edit your Subject line so it is more specific
than "Re: Contents of Pharo-users digest..."
Today's Topics:
�� ��1. Re: Semaphore wait and signal (Ben Coman)
�� ��2. Re: (no subject) (Ben Coman)
�� ��3. Re: (no subject) (phil@highoctane.be)
�� ��4. SPLASH 2016: Call for Sponsorships (Tijs van der Storm)
----------------------------------------------------------------------
Message: 1
Date: Wed, 11 May 2016 00:28:32 +0800
From: Ben Coman <btc@openinworld.com>
To: Any question about pharo is welcome <pharo-users@lists.pharo.org>
Subject: Re: [Pharo-users] Semaphore wait and signal
Message-ID:
�� �� �� �� <CAProBTnUgFZBiGqi3QdamUdG=TsKMcyNyoPSNhTpS2D0zG3Jvg@mail.gmail.com>
Content-Type: text/plain; charset=UTF-8
On Tue, May 10, 2016 at 6:31 PM, Vince Refiti <vinref@gmail.com> wrote:
> Hello
>
> I am playing around with Semaphore, and wrote the following:
>
> | coll count sem |
> coll := Array withAll: (1 to: 100).
> count := 0.
> sem := Semaphore new.
> coll do: [ :each |
>�� �� ��count := count + 1.
>�� �� ��(count >= 5)
>�� �� �� �� ��ifTrue: [
>�� �� �� �� �� �� ��Transcript show: 'waiting...'; cr.
>�� �� �� �� �� �� ��sem wait ].
>
>�� �� ��[ [ 2 seconds asDelay wait.
>�� �� �� �� �� Transcript show: each printString, ' ', count printString; cr ]
> ensure: [
>�� �� �� �� �� �� ��count := count -1.
>�� �� �� �� �� �� ��sem signal ] ] fork ]
>
> The output is:
[snipped]
> I was expecting 'waiting...' to alternate with the 'each-count' lines. Also
> the entire statement paused for 2 seconds, spat out some lines, then waited
> a little longer, and then finished.
>
> Can someone please explain this pattern?
>
> Thanks, Vince
Hi Vince,
General things to be aware of...
* Transcript is not perturbing your result.
* Playground code is executed in the context of the main UI-process. Thus...
�� * An infinite loop will lock the UI.
�� * A sem wait will lock the UI.
* Processes at the same priority are scheduled cooperatively.
* Processes at different priority are pre-emptively scheduled.
I refactored your example to better highlight program flow...
| coll count sem |
Transcript clear.
coll := Array withAll: (1 to: 99).
count := 0.
sem := Semaphore new.
coll do:
[�� ��:each |
�� �� count := count + 1.
�� ��Transcript crShow: each printString; tab; tab; show: count printString, '+'.
�� ��(count >= 5) ifTrue:
�� �� �� �� ��[ sem isSignaled
�� �� �� �� �� �� ��ifTrue: [�� ��Transcript tab; show: ' nowait'.
�� �� �� �� �� �� �� �� �� �� �� �� �� �� �� sem wait ]
�� �� �� �� �� �� ��ifFalse: [ Transcript tab; show: ' wait'.
�� �� �� �� �� �� �� �� �� �� �� �� �� �� ��sem wait.
�� �� �� �� �� �� �� �� �� �� �� �� �� �� ��Transcript crShow: each printString; tab;
tab; show: count printString; tab; show: ' postwait, excessSignals ' ,
sem excessSignals printString. ]
].
�� ��[�� Transcript crShow: ' ', each printString; tab; tab; show: count
printString; tab; show: ' delay'.
�� �� �� 2 seconds asDelay wait.
�� �� �� ��count := count -1.
�� �� �� Transcript crShow: ' ', each printString; tab ; tab; show: count
printString, '-'; tab; show: ' signal'.
�� �� �� sem signal.
�� �� ] fork.
]
You will need to add...
�� �� Semaphore>>excessSignals
�� �� �� �� ��^excessSignals
For counts 1, 2, 3 & 4, forked processes -1 to -4 are queued to run,
but don't run until the UI-process suspended by the wait at each=5,
count=5, which is why the "waiting..." tag appears first.
When the UI-process waits, processes -1 to -4 run in turn and
immediately delay for two seconds. After this, they queued to run.
Process-1 signals the UI-process to be queued to run.�� But processes
-2 to -4 run first, signalling sem an extra three times.
When the UI-process resumes, each=5, count=1 and sem has three
excessSignals.�� Completing the do: adds process -5 to the run queue.
Then counts 2, 3, & 4 queues processes -6, -7 & -8 to run.�� Counts 5,
6 & 7 consume the excessSignals without suspending, queing processes
-9, -10 & -11 to run.
At count=8, the UI-process suspends at the wait, and process -5 runs.
This signals the UI-process to be queued to run.�� Processes -6 to -11
run, signalling sem an extra six times.
When the UI-process resumes, each=12, count=1 and sem has six
excessSignals.�� Completing the do: adds process -12 to the run queue.
Then counts 2, 3, & 4 queues processes -13, -14 & -15 to run.�� Counts
5, 6, 7, 8, 9, 10 consume the excessSignals without suspending, queing
processes -16, -17, -18, -19, -20, -21 to run.
At count=11, the UI-process suspends at the wait, and process -12
runs.�� This signals the UI-process to be queued to run.�� Processes -13
to -21 run, signalling sem an extra nine times.
ecetera...
btw, The delay doesn't make much difference to how the forked
processes interact with the main UI-process, since all forked
processes execute before the UI-process resumed. It just interleaves
the delay/signal tags rather than grouping them.
1 1+
2 2+
3 3+
4 4+
5 5+ wait
��1 5 delay
��2 5 delay
��3 5 delay
��4 5 delay
��1 4- signal
��2 3- signal
��3 2- signal
��4 1- signal
5 1 postwait, excessSignals 3
6 2+
7 3+
8 4+
9 5+ nowait
10 6+ nowait
11 7+ nowait
12 8+ wait
��5 8 delay
��6 8 delay
��7 8 delay
��8 8 delay
��9 8 delay
��10 8 delay
��11 8 delay
��5 7- signal
��6 6- signal
��7 5- signal
��8 4- signal
��9 3- signal
��10 2- signal
��11 1- signal
12 1 postwait, excessSignals 6
13 2+
14 3+
15 4+
16 5+ nowait
17 6+ nowait
18 7+ nowait
19 8+ nowait
20 9+ nowait
21 10+ nowait
22 11+ wait
��12 11 delay
��13 11 delay
��14 11 delay
��15 11 delay
��16 11 delay
��17 11 delay
��18 11 delay
��19 11 delay
��20 11 delay
��21 11 delay
��12 10- signal
��13 9- signal
��14 8- signal
��15 7- signal
��16 6- signal
��17 5- signal
��18 4- signal
��19 3- signal
��20 2- signal
��21 1- signal
22 1 postwait, excessSignals 9
23 2+
24 3+
25 4+
26 5+ nowait
27 6+ nowait
28 7+ nowait
29 8+ nowait
30 9+ nowait
31 10+ nowait
32 11+ nowait
33 12+ nowait
34 13+ nowait
35 14+ wait
��22 14 delay
��23 14 delay
��24 14 delay
��25 14 delay
��26 14 delay
��27 14 delay
��28 14 delay
��29 14 delay
��30 14 delay
��31 14 delay
��32 14 delay
��33 14 delay
��34 14 delay
��22 13- signal
��23 12- signal
��24 11- signal
��25 10- signal
��26 9- signal
��27 8- signal
��28 7- signal
��29 6- signal
��30 5- signal
��31 4- signal
��32 3- signal
��33 2- signal
��34 1- signal
35 1 postwait, excessSignals 12
36 2+
37 3+
38 4+
39 5+ nowait
40 6+ nowait
41 7+ nowait
42 8+ nowait
43 9+ nowait
44 10+ nowait
45 11+ nowait
46 12+ nowait
47 13+ nowait
48 14+ nowait
49 15+ nowait
50 16+ nowait
51 17+ wait
��35 17 delay
��36 17 delay
��37 17 delay
��38 17 delay
��39 17 delay
��40 17 delay
��41 17 delay
��42 17 delay
��43 17 delay
��44 17 delay
��45 17 delay
��46 17 delay
��47 17 delay
��48 17 delay
��49 17 delay
��50 17 delay
��35 16- signal
��36 15- signal
��37 14- signal
��38 13- signal
��39 12- signal
��40 11- signal
��41 10- signal
��42 9- signal
��43 8- signal
��44 7- signal
��45 6- signal
��46 5- signal
��47 4- signal
��48 3- signal
��49 2- signal
��50 1- signal
51 1 postwait, excessSignals 15
52 2+
53 3+
54 4+
55 5+ nowait
56 6+ nowait
57 7+ nowait
58 8+ nowait
59 9+ nowait
60 10+ nowait
61 11+ nowait
62 12+ nowait
63 13+ nowait
64 14+ nowait
65 15+ nowait
66 16+ nowait
67 17+ nowait
68 18+ nowait
69 19+ nowait
70 20+ wait
��51 20 delay
��52 20 delay
��53 20 delay
��54 20 delay
��55 20 delay
��56 20 delay
��57 20 delay
��58 20 delay
��59 20 delay
��60 20 delay
��61 20 delay
��62 20 delay
��63 20 delay
��64 20 delay
��65 20 delay
��66 20 delay
��67 20 delay
��68 20 delay
��69 20 delay
��51 19- signal
��52 18- signal
��53 17- signal
��54 16- signal
��55 15- signal
��56 14- signal
��57 13- signal
��58 12- signal
��59 11- signal
��60 10- signal
��61 9- signal
��62 8- signal
��63 7- signal
��64 6- signal
��65 5- signal
��66 4- signal
��67 3- signal
��68 2- signal
��69 1- signal
70 1 postwait, excessSignals 18
71 2+
72 3+
73 4+
74 5+ nowait
75 6+ nowait
76 7+ nowait
77 8+ nowait
78 9+ nowait
79 10+ nowait
80 11+ nowait
81 12+ nowait
82 13+ nowait
83 14+ nowait
84 15+ nowait
85 16+ nowait
86 17+ nowait
87 18+ nowait
88 19+ nowait
89 20+ nowait
90 21+ nowait
91 22+ nowait
92 23+ wait
��70 23 delay
��71 23 delay
��72 23 delay
��73 23 delay
��74 23 delay
��75 23 delay
��76 23 delay
��77 23 delay
��78 23 delay
��79 23 delay
��80 23 delay
��81 23 delay
��82 23 delay
��83 23 delay
��84 23 delay
��85 23 delay
��86 23 delay
��87 23 delay
��88 23 delay
��89 23 delay
��90 23 delay
��91 23 delay
��70 22- signal
��71 21- signal
��72 20- signal
��73 19- signal
��74 18- signal
��75 17- signal
��76 16- signal
��77 15- signal
��78 14- signal
��79 13- signal
��80 12- signal
��81 11- signal
��82 10- signal
��83 9- signal
��84 8- signal
��85 7- signal
��86 6- signal
��87 5- signal
��88 4- signal
��89 3- signal
��90 2- signal
��91 1- signal
92 1 postwait, excessSignals 21
93 2+
94 3+
95 4+
96 5+ nowait
97 6+ nowait
98 7+ nowait
99 8+ nowait
��92 8 delay
��93 8 delay
��94 8 delay
��95 8 delay
��96 8 delay
��97 8 delay
��98 8 delay
��99 8 delay
��92 7- signal
��93 6- signal
��94 5- signal
��95 4- signal
��96 3- signal
��97 2- signal
��98 1- signal
��99 0- signal
------------------------------
Message: 2
Date: Wed, 11 May 2016 00:51:12 +0800
From: Ben Coman <btc@openinworld.com>
To: Any question about pharo is welcome <pharo-users@lists.pharo.org>
Subject: Re: [Pharo-users] (no subject)
Message-ID:
�� �� �� �� <CAProBT=Xvj67KV6CG+tb6qa=jATTBuX+bgc3AnWMAz9A19x_HQ@mail.gmail.com>
Content-Type: text/plain; charset=UTF-8
On Tue, May 10, 2016 at 8:52 PM, Franklin Mike
<mike1corporation@gmail.com> wrote:
> Hi !
>
> I'm new on pharo and I realy like its vision. To learn more about the system
> I decide to write a package that handle Webcam. The package should be able
> to :
>
> - start webcam
> - take photo
> - record a video.
>
> The wonderfull thing is that I don't know where to start, Every advice is
> welcome.
I guess you will need to interface to some library, so for Pharo 5
have a play with its new UFFI interface.
A quick google around shows opencv to be a common base for FFI...
http://opencvlover.blogspot.com.au/2011/07/accesing-camera-using-opencv.html
but I also found this...
http://itseez.com/tags/openvx/
Note that NativeBoost was an FFI implementation for Pharo 4.
cheers -ben
------------------------------
Message: 3
Date: Tue, 10 May 2016 22:55:42 +0200
From: "phil@highoctane.be" <phil@highoctane.be>
To: Any question about pharo is welcome <pharo-users@lists.pharo.org>
Subject: Re: [Pharo-users] (no subject)
Message-ID:
�� �� �� �� <CAMynPtw0Yy+zP5Lh2VwXPCYQvM5h+RYBBchHj-s-HciWPkwEFA@mail.gmail.com>
Content-Type: text/plain; charset="utf-8"
There is a camera plugin in the source tree of the VM.
pharo-vm/platforms/win32/plugins/CameraPlugin
You can copy the dll in the Pharo directory and load the dll with:
NativeBoost forCurrentPlatform loadModule: 'CameraPlugin.dll'
Anyone having the FFI calls?
Maybe Phratch has it built in.
Phil
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://lists.pharo.org/pipermail/pharo-users_lists.pharo.org/attachments/20160510/d260e304/attachment-0001.html>
------------------------------
Message: 4
Date: Tue, 10 May 2016 22:59:10 +0000
From: Tijs van der Storm <storm@cwi.nl>
To: "pharo-users@lists.pharo.org" <pharo-users@lists.pharo.org>
Subject: [Pharo-users] SPLASH 2016: Call for Sponsorships
Message-ID:
�� �� �� �� <CAOzQwNNDWBYOCafYezyS1_WpfxbWFLpFboPL2nM9YbghQWdDmw@mail.gmail.com>
Content-Type: text/plain; charset="utf-8"
The ACM SIGPLAN conference on Systems, Programming, Languages and
Applications: Software for Humanity (SPLASH) embraces all aspects of
software construction and delivery to make it the premier conference at the
intersection of programming, languages, and software engineering. SPLASH
2016 will take place from Sunday, October 30 to Friday, November 4, 2016 in
Amsterdam, The Netherlands.
Web version of this call for sponsorships:
http://2016.splashcon.org/attending/support-program
SPLASH is where the best of the best in software innovation, programming
and programming languages convene, learn from and inspire each other, and
share their passion for software. Supporting SPLASH is an opportunity to
put your corporate name in front of this community ? a superb investment
for your organization.
# Sponsorship Packages
## Diamond: $US 15 000
Benefits:
- Recognition as a supporter in print and on the web. Recognized as a
Diamond supporter on registration brochures and conference program
- Two company-provided items placed in the conference tote bag
- Official exclusive support for your choice of (subject to availability):
Doctoral Symposium, Poster Session, Keynotes, or support for 8 Student
Volunteers named for your organization
- Attendance (for two) at an invitation-only reception by the SPLASH
General Chair
- Choice of: two Full conference registrations; or two complimentary main
conference registrations plus two complimentary one-day pass registrations
## Gold: $US 10 000
Benefits:
- Recognition as a supporter in print and on the web. Recognized as a Gold
supporter on registration brochures and conference program
- Two company-provided items placed in the conference tote bag
- Official support for your choice of (subject to availability): Doctoral
Symposium, Poster Session, Keynotes, or support for 6 Student Volunteers
named for your organization
- Attendance (for two) at an invitation-only reception by the SPLASH
General Chair
- Choice of: one Full conference registration plus one complimentary main
conference registration; or two complimentary main conference registrations
plus one complimentary one-day pass registration
## Silver: $US 5000
Benefits:
- Recognition as a supporter in print and on the web. Recognized as a
Silver supporter on registration brochures and conference program
- One company-provided item placed in the conference tote bag
- Official support for your choice of: four Student Volunteers named for
your organization; or the Keynotes (non-exclusive support)
- Attendance (for two) at an invitation-only reception by the SPLASH
General Chair
- Your choice of: one Full conference registration; or one complimentary
main conference registration plus one complimentary one-day pass
registration; or three complimentary one-day pass registrations
## Bronze $US 3000
- Recognition as a supporter in print and on the web. Recognized as a
Bronze supporter on registration brochures and conference program
- One company-provided one-page insert placed in conference tote bag
- Official support for two Student Volunteers named for your organization
- Attendance (for one) at an invitation-only reception by the SPLASH
General Chair
- Your choice of: one complimentary main conference registration; or two
complimentary one-day pass registrations
# Why sponsor SPLASH?
SPLASH values innovation, collaboration, and diversity. For many software
researchers, academics, students, educators, and practitioners, SPLASH is
the most important conference of the year. It is a place to:
- improve skills and productivity, independent of any particular product or
vendor;
- gain a global perspective connecting with world experts; and
- discover and explore new trends and innovations in leading edge research
and practice.
Becoming a SPLASH corporate supporter demonstrates your leadership and
commitment to the community. It is an opportunity to:
- carry your message to community leaders;
- associate your brand with world-class research and development;
- position your company as a leader in the field; and
- prepare for the future.
Your corporate name and logo will be in front of the entire community
throughout the conference. For the same contribution you also receive
either complimentary or discounted SPLASH registrations for use by your
organization. You will also have the opportunity to participate in
invitation-only events that will provide you with direct, one-on-one
interactions with some key members of the SPLASH community.
Thank you for your time! Please do not hesitate to contact us at
support@splashcon.org. We look forward to helping you make the most of your
investment in SPLASH.
Jurgen Vinju
SPLASH 2016 Sponsorship Chair
Eelco Visser
SPLASH 2016 General Chair
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://lists.pharo.org/pipermail/pharo-users_lists.pharo.org/attachments/20160510/1960f486/attachment.html>
------------------------------
Subject: Digest Footer
_______________________________________________
Pharo-users mailing list
Pharo-users@lists.pharo.org
http://lists.pharo.org/mailman/listinfo/pharo-users_lists.pharo.org
------------------------------
End of Pharo-users Digest, Vol 37, Issue 28
*******************************************