Sergey,
I am responsible for much of the Rosetta code contributions (thanks also to
Steve, Andrew, Matt, Peter, and about 4 others) and this one in particular
dating from 2010. As I recall this was before the multi-threading versions were
widely available. I think multi-threading is underrepresented in Rosetta/Unicon.
If you come up with a multi-threading version, we should add it to the post as
an alternative version. If you don't feel comfortable doing this, post the
code and I can add it.
David
From: Sergey Logichev <[email protected]>
To: Jafar Al-Gharaibeh <[email protected]>
Cc: Unicon group <[email protected]>
Sent: Sunday, January 11, 2015 1:16 AM
Subject: Re: [Unicon-group] Walk of file directory
Jafar, Thank you for a whole bundle of advices and suggestions! Threads are
worth to try. The thought of search by file attributes is very useful too. Your
suggestion about slow I/O partly is right. For UNIX I tried the program on
Raspberry Pi with 6 Class microSD as HDD (it's slow, agree). But for Windows it
was quite fast HDD. It would be interesting to compare performance of the
program on Windows with classic approach based on Win32 _FINDFIRST, _FINDNEXT
functions. I have threaded Delphi/Lazarus implementations of this algorithm.
Feel that it will be faster but in which degree? Sergey 10.01.2015, 21:50,
"Jafar Al-Gharaibeh" <[email protected]>:
Sergey, There are so many things that came to mind when I saw your program.
1- At the end of your email, sourceforge ad says "Go Parallel", Which is not a
bad idea for this highly parallel application. There is a similar program
"wordcount" listed in my dissertation (available on unicon.org) that go through
directories and count words in every file using threads (Chapter 7, page 107)
2- Unicon open() already supports " pattern matching that would greatly (I
believe) speedup your program. For example you can do this: L :=
open("*.icn") to get a list of all of Unicon source files in the current
directory. Note: It would be nice if there were a way to tell open() to
return files not only based on a pattern, but also on file attribute to allow
something like "get me all directories in the current directory", or "get me
all read only file". There are a lot of situations where filtering directory
names for example is very useful - like this program 3- The program on Rosetta
Code is not optimized for speed. You can minimize the number of lists created
and put() by careful rewriting of the code. 4- Depending on how deep the
directory tree is, there might be a lot of I/O going on. A slow disk might
limit how fast you can go regardless of how optimized your code is. I will
share results if get around trying any of these options. Cheers,Jafar
On Sat, Jan 10, 2015 at 5:51 AM, Sergey Logichev <[email protected]> wrote:
Hello all! Now I investigate the best approach to get list of files in
specified directory and beneath in Unicon.I found excellent example at
rosettacode.org:
http://rosettacode.org/wiki/Walk_a_directory/Recursively#Icon_and_Unicon I
reconstructed this one to implement matching of filenames to specified pattern
(regular expression). My program recursively walks a directory and prints
appropriate filenames. The same as dir (ls) does. All working fine except
performance. If directory has a lot of subdirs the search may took 10-20
seconds before starting output. Could you provide some advices how to enchance
the performance? Some notes how to make and use. Unpack content of udir.zip to
your local directory. Define which environment you use in env.icn file -
uncomment line "$define _UNIX 1" in the case of UNIX. Nothing to do in the case
of Windows.Make udir program:unicon -c futils.icnunicon -c options.icnunicon -c
regexp.icnunicon udir.icn Usage: udir -f<filemask>for example: udir
-f*.icnshall list of icn files in the current dir and all its subdirectories.
Best regards,Sergey Logichev
------------------------------------------------------------------------------
Dive into the World of Parallel Programming! The Go Parallel Website,
sponsored by Intel and developed in partnership with Slashdot Media, is your
hub for all things parallel software development, from weekly thought
leadership blogs to news, videos, case studies, tutorials and more. Take a
look and join the conversation now. http://goparallel.sourceforge.net
_______________________________________________
Unicon-group mailing list
[email protected]
https://lists.sourceforge.net/lists/listinfo/unicon-group
------------------------------------------------------------------------------
Dive into the World of Parallel Programming! The Go Parallel Website,
sponsored by Intel and developed in partnership with Slashdot Media, is your
hub for all things parallel software development, from weekly thought
leadership blogs to news, videos, case studies, tutorials and more. Take a
look and join the conversation now. http://goparallel.sourceforge.net
_______________________________________________
Unicon-group mailing list
[email protected]
https://lists.sourceforge.net/lists/listinfo/unicon-group
------------------------------------------------------------------------------
Dive into the World of Parallel Programming! The Go Parallel Website,
sponsored by Intel and developed in partnership with Slashdot Media, is your
hub for all things parallel software development, from weekly thought
leadership blogs to news, videos, case studies, tutorials and more. Take a
look and join the conversation now. http://goparallel.sourceforge.net
_______________________________________________
Unicon-group mailing list
[email protected]
https://lists.sourceforge.net/lists/listinfo/unicon-group
