Search Results

Search found 4940 results on 198 pages for 'feed reader'.

Page 180/198 | < Previous Page | 176 177 178 179 180 181 182 183 184 185 186 187  | Next Page >

• realtime diagnostics

  - by Ion Todirel

  I have an application which has a loop, part of a "Scheduler", which runs at all time and is the heart of the application. Pretty much like a game loop, just that my application is a WPF application and it's not a game. Naturally the application does logging at many points, but the Scheduler does some sensitive monitoring, and sometimes it's impossible just from the logs to tell what may have gotten wrong (and by wrong I don't mean exceptions) or the current status. Because Scheduler's inner loop runs at short intervals, you can't do file I/O-based logging (or using the Event Viewer) in there. First, you need to watch it in real-time, and secondly the log file would grow in size very fast. So I was thinking of ways to show this data to the user in the realtime, some things I considered: Display the data in realtime in the UI Use AllocConsole/WriteConsole to display this information in a console Use a different console application which would display this information, communicate between the Scheduler and the console app using pipes or other IPC techniques Use Windows' Performance Monitor and somehow feed it with this information ETW Displaying in the UI would have its issues. First it doesn't integrate with the UI I had in mind for my application, and I don't want to complicate the UI just for this. This diagnostics would only happen rarely. Secondly, there is going to be some non-trivial data protection, as the Scheduler has it's own thread. A separate console window would work probably, but I'm still worried if it's not too much threshold. Allocating my own console, as this is a windows app, would probably be better than a different console application (3), as I don't need to worry about IPC communication, and non-blocking communication. However a user could close the console I allocated, and it would be problematic in that case. With a separate process you don't have to worry about it. Assuming there is an API for Performance Monitor, it wouldn't be integrated too well with my app or apparent to the users. Using ETW also doesn't solve anything, just a random idea, I still need to display this information somehow. What others think, would there be other ways I missed?

  Read the article

• Connected host failed to respond (internal NAT address)

  - by MostRandom

  I'm writing my first C# web application that connects to an XML based service. It requires that I present a certificate and feed the XML stream. It seems to authenticate properly but then it gives the following error: A connection attempt failed because the connected party did not properly respond after a period of time, or established connection failed because connected host has failed to respond 10.1.10.4:3128 The funny thing is that I'm not on a proxy or anything like that. I'm connecting directly to the internet. At one point I we did use a proxy that with internal NAT address. So my question is: Does Visual Studio have some sort of default proxy setting that I need to change? This IP is no longer used for anything, so I know that I don't need to use any proxy authentication code. using System; using System.Data; using System.Configuration; using System.Collections; using System.Web; using System.Net; using System.Security.Cryptography.X509Certificates; using System.Web.Security; using System.Web.UI; using System.Web.UI.WebControls; using System.Web.UI.WebControls.WebParts; using System.Web.UI.HtmlControls; namespace WebApplication1 { public partial class _Default : System.Web.UI.Page { protected void Page_Load(object sender, EventArgs e) { Uri requestURI = new Uri("*site omitted*"); //Create the Request Object HttpWebRequest pageRequest = (HttpWebRequest)WebRequest.Create(requestURI); //After installing the cert on the server export a client cert to the working directory as Deluxe.cer string certFile = "*certificate omitted*"; X509Certificate cert = X509Certificate.CreateFromCertFile(certFile); //Pull in your Data, if it is from an external xml as below or create an xml string with variables if a dynamic post is required. string xmlPath = "*XML omitted*"; System.Xml.XmlDocument passXML = new System.Xml.XmlDocument(); passXML.Load(xmlPath); //XML String with the data needed to pass string postData = passXML.OuterXml; //Set the Request Object parameters pageRequest.ContentType = "application/x-www-form-urlencoded"; pageRequest.Method = "POST"; pageRequest.AllowWriteStreamBuffering = false; pageRequest.AllowAutoRedirect = false; pageRequest.ClientCertificates.Add(cert); postData = "xml_data=" + Server.UrlEncode(postData); pageRequest.ContentLength = postData.Length; //Create the Post Stream Object System.IO.StreamWriter postStream = new System.IO.StreamWriter(pageRequest.GetRequestStream()); //Write the data to the post stream postStream.Write(postData); postStream.Flush(); postStream.Close(); //Set the Response Object HttpWebResponse postResponse = (HttpWebResponse)pageRequest.GetResponse();

  Read the article

• M-V-VM, isn't the Model leaking into the View?

  - by BFree

  The point of M-V-VM as we all know is about speraration of concerns. In patterns like MVVM, MVC or MVP, the main purpose is to decouple the View from the Data thereby building more flexible components. I'll demonstrate first a very common scenario found in many WPF apps, and then I'll make my point: Say we have some StockQuote application that streams a bunch of quotes and displays them on screen. Typically, you'd have this: StockQuote.cs : (Model) public class StockQuote { public string Symbol { get; set; } public double Price { get; set; } } StockQuoteViewModel.cs : (ViewModel) public class StockQuoteViewModel { private ObservableCollection<StockQuote> _quotes = new ObservableCollection<StockQuote>(); public ObservableCollection<StockQuote> Quotes { get { return _quotes; } } } StockQuoteView.xaml (View) <Window x:Class="WpfApplication1.Window1" xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation" xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml" xmlns:local="clr-namespace:WpfApplication1" Title="Window1" Height="300" Width="300"> <Window.DataContext> <local:StockQuoteViewModel/> </Window.DataContext> <Window.Resources> <DataTemplate x:Key="listBoxDateTemplate"> <StackPanel Orientation="Horizontal"> <TextBlock Text="{Binding Symbol}"/> <TextBlock Text="{Binding Price}"/> </StackPanel> </DataTemplate> </Window.Resources> <Grid> <ListBox ItemTemplate="{StaticResource listBoxDateTemplate}" ItemsSource="{Binding Quotes}"/> </Grid> </Window> And then you'd have some kind of service that would feed the ObservableCollection with new StockQuotes. My question is this: In this type of scenario, the StockQuote is considered the Model, and we're exposing that to the View through the ViewModel's ObservableCollection. Which basically means, our View has knowledge of the Model. Doesn't that violate the whole paradigm of M-V-VM? Or am I missing something here....?

  Read the article

• Java: Reading a pdf file from URL into Byte array/ByteBuffer in an applet.

  - by Pol

  I'm trying to figure out why this particular snippet of code isn't working for me. I've got an applet which is supposed to read a .pdf and display it with a pdf-renderer library, but for some reason when I read in the .pdf files which sit on my server, they end up as being corrupt. I've tested it by writing the files back out again. I've tried viewing the applet in both IE and Firefox and the corrupt files occur. Funny thing is, when I trying viewing the applet in Safari (for Windows), the file is actually fine! I understand the JVM might be different, but I am still lost. I've compiled in Java 1.5. JVMs are 1.6. The snippet which reads the file is below. public static ByteBuffer getAsByteArray(URL url) throws IOException { ByteArrayOutputStream tmpOut = new ByteArrayOutputStream(); URLConnection connection = url.openConnection(); int contentLength = connection.getContentLength(); InputStream in = url.openStream(); byte[] buf = new byte[512]; int len; while (true) { len = in.read(buf); if (len == -1) { break; } tmpOut.write(buf, 0, len); } tmpOut.close(); ByteBuffer bb = ByteBuffer.wrap(tmpOut.toByteArray(), 0, tmpOut.size()); //Lines below used to test if file is corrupt //FileOutputStream fos = new FileOutputStream("C:\\abc.pdf"); //fos.write(tmpOut.toByteArray()); return bb; } I must be missing something, and I've been banging my head trying to figure it out. Any help is greatly appreciated. Thanks. Edit: To further clarify my situation, the difference in the file before I read then with the snippet and after, is that the ones I output after reading are significantly smaller than they originally are. When opening them, they are not recognized as .pdf files. There are no exceptions being thrown that I ignore, and I have tried flushing to no avail. This snippet works in Safari, meaning the files are read in it's entirety, with no difference in size, and can be opened with any .pdf reader. In IE and Firefox, the files always end up being corrupted, consistently the same smaller size. I monitored the len variable (when reading a 59kb file), hoping to see how many bytes get read in at each loop. In IE and Firefox, at 18kb, the in.read(buf) returns a -1 as if the file has ended. Safari does not do this. I'll keep at it, and I appreciate all the suggestions so far.

  Read the article

• Bidirectional FIFO

  - by nunos

  I would like to implement a bidirectional fifo. The code below is functioning but it is not using bidirectional fifo. I have searched all over the internet, but haven't found any good example... How can I do that? Thanks, WRITER.c: #include <stdio.h> #include <unistd.h> #include <string.h> #include <sys/types.h> #include <sys/wait.h> #include <fcntl.h> #define MAXLINE 4096 #define READ 0 #define WRITE 1 int main (int argc, char** argv) { int a, b, fd; do { fd=open("/tmp/myfifo",O_WRONLY); if (fd==-1) sleep(1); } while (fd==-1); while (1) { scanf("%d", &a); scanf("%d", &b); write(fd,&a,sizeof(int)); write(fd,&b,sizeof(int)); if (a == 0 && b == 0) { break; } } close(fd); return 0; } READER.c: #include <stdio.h> #include <unistd.h> #include <string.h> #include <sys/types.h> #include <sys/wait.h> #include <fcntl.h> #include <sys/stat.h> #define MAXLINE 4096 #define READ 0 #define WRITE 1 int main(void) { int n1, n2; int fd; mkfifo("/tmp/myfifo",0660); fd=open("/tmp/myfifo",O_RDONLY); while(read(fd, &n1, sizeof(int) )) { read(fd, &n2, sizeof(int)); if (n1 == 0 && n2 == 0) { break; } printf("soma: %d\n",n1+n2); printf("diferenca: %d\n", n1-n2); printf("divisao: %f\n", n1/(double)n2); printf("multiplicacao: %d\n", n1*n2); } close(fd); return 0; }

  Read the article

• Problem with type coercion and string concatenation in JavaScript in Greasemonkey script on Firefox

  - by Yi Jiang

  I'm creating a GreaseMonkey script to improve the user interface of the 10k tools Stack Overflow uses. I have encountered an unreproducible and frankly bizarre problem that has confounded me and the others in the JavaScript room on SO Chat. We have yet to find the cause after several lengthy debugging sessions. The problematic script can be found here. Source - Install The problem occurs at line 85, the line after the 'vodoo' comment: return (t + ' (' + +(+f.offensive + +f.spam) + ')'); It might look a little weird, but the + in front of the two variables and the inner bracket is for type coercion, the inner middle + is for addition, and the other ones are for concatenation. Nothing special, but observant reader might note that type coercion on the inner bracket is unnecessary, since both are already type coerced to numbers, and type coercing result is useless when they get concatenated into a string anyway. Not so! Removing the + breaks the script, causing f.offensive and f.spam to be concatenated instead of added together. Adding further console.log only makes things more confusing: console.log(f.offensive + f.spam); // 50 console.log('' + (+f.offensive + +f.spam)); // 5, but returning this yields 50 somehow console.log('' + (+f.offensive + +f.spam) + ''); // 50 Source: http://chat.stackoverflow.com/transcript/message/203261#203261 The problem is that this is unreproducible - running scripts like console.log('a' + (+'3' + +'1') + 'b'); in the Firebug console yields the correct result, as does (function(){ return 'a' + (+'3' + +'1') + 'b'; })(); Even pulling out large chunks of the code and running them in the console does not reproduce this bug: $('.post-menu a[id^=flag-post-]').each(function(){ var f = {offensive: '4', spam: '1'}; if(f){ $(this).text(function(i, t){ // Vodoo - please do not remove the '+' in front of the inner bracket return (t + ' (' + +(+f.offensive + +f.spam) + ')'); }); } }); Tim Stone in the chatroom has reproduction instruction for those who are below 10k. This bug only appears in Firefox - Chrome does not appear to exhibit this problem, leading me to believe that this may be a problem with either Firefox's JavaScript engine, or the Greasemonkey add-on. Am I right? I can be found in the JavaScript room if you want more detail and/or want to discuss this.

  Read the article

• How to I serialize a large graph of .NET object into a SQL Server BLOB without creating a large bu

  - by Ian Ringrose

  We have code like: ms = New IO.MemoryStream bin = New System.Runtime.Serialization.Formatters.Binary.BinaryFormatter bin.Serialize(ms, largeGraphOfObjects) dataToSaveToDatabase = ms.ToArray() // put dataToSaveToDatabase in a Sql server BLOB But the memory steam allocates a large buffer from the large memory heap that is giving us problems. So how can we stream the data without needing enough free memory to hold the serialized objects. I am looking for a way to get a Stream from SQL server that can then be passed to bin.Serialize() so avoiding keeping all the data in my processes memory. Likewise for reading the data back... Some more background. This is part of a complex numerical processing system that processes data in near real time looking for equipment problems etc, the serialization is done to allow a restart when there is a problem with data quality from a data feed etc. (We store the data feeds and can rerun them after the operator has edited out bad values.) Therefore we serialize the object a lot more often then we de-serialize them. The objects we are serializing include very large arrays mostly of doubles as well as a lot of small “more normal” objects. We are pushing the memory limit on a 32 bit system and make the garage collector work very hard. (Effects are being made elsewhere in the system to improve this, e.g. reusing large arrays rather then create new arrays.) Often the serialization of the state is the last straw that courses an out of memory exception; our peak memory usage is while this serialization is being done. I think we get large memory pool fragmentation when we de-serialize the object, I expect there are also other problem with large memory pool fragmentation given the size of the arrays. (This has not yet been investigated, as the person that first looked at this is a numerical processing expert, not a memory management expert.) Are customers use a mix of Sql Server 2000, 2005 and 2008 and we would rather not have different code paths for each version of Sql Server if possible. We can have many active models at a time (in different process, across many machines), each model can have many saved states. Hence the saved state is stored in a database blob rather then a file. As the spread of saving the state is important, I would rather not serialize the object to a file, and then put the file in a BLOB one block at a time. Other related questions I have asked How to Stream data from/to SQL Server BLOB fields? Is there a SqlFileStream like class that works with Sql Server 2005?

  Read the article

• iPhone - database reading method and memory leaks

  - by Do8821

  Hi, in my application, a RSS reader, I get memory leaks that I can't fix because I can't understand from where they come from. Here is the code pointed out by Instruments. -(void) readArticlesFromDatabase { [self setDatabaseInfo]; sqlite3 *database; articles = [[NSMutableArray alloc] init]; if(sqlite3_open([databasePath UTF8String], &database) == SQLITE_OK) { const char *sqlStatement = "select * from articles"; if(sqlite3_prepare_v2(database, sqlStatement, -1, &compiledStatement, NULL) == SQLITE_OK) { while(sqlite3_step(compiledStatement) == SQLITE_ROW) { NSString *aName = [NSString stringWithUTF8String:(char *)sqlite3_column_text(compiledStatement, 1)]; NSString *aDate = [NSString stringWithUTF8String:(char *)sqlite3_column_text(compiledStatement, 2)]; NSString *aUrl = [NSString stringWithUTF8String:(char *)sqlite3_column_text(compiledStatement, 3)]; NSString *aCategory = [NSString stringWithUTF8String:(char *)sqlite3_column_text(compiledStatement, 4)]; NSString *aAuthor = [NSString stringWithUTF8String:(char *)sqlite3_column_text(compiledStatement, 5)]; NSString *aSummary = [NSString stringWithUTF8String:(char *)sqlite3_column_text(compiledStatement, 6)]; NSMutableString *aContent = [NSMutableString stringWithUTF8String:(char *)sqlite3_column_text(compiledStatement, 7)]; NSString *aNbrComments = [NSString stringWithUTF8String:(char *)sqlite3_column_text(compiledStatement, 8)]; NSString *aCommentsLink = [NSString stringWithUTF8String:(char *)sqlite3_column_text(compiledStatement, 9)]; NSString *aPermalink = [NSString stringWithUTF8String:(char *)sqlite3_column_text(compiledStatement, 11)]; [aContent replaceCharactersInRange: [aContent rangeOfString: @"http://www.mywebsite.com/img/action-on.gif"] withString: @"hellocoton-action-on.gif"]; [aContent replaceCharactersInRange: [aContent rangeOfString: @"hhttp://www.mywebsite.com/img/action-on-h.gif"] withString: @"hellocoton-action-on-h.gif"]; [aContent replaceCharactersInRange: [aContent rangeOfString: @"hthttp://www.mywebsite.com/img/hellocoton.gif"] withString: @"hellocoton-hellocoton.gif"]; NSString *imageURLBrut = [self parseArticleForImages:aContent]; NSString *imageURLCache = [imageURLBrut stringByReplacingOccurrencesOfString:@":" withString:@"_"]; imageURLCache = [imageURLCache stringByReplacingOccurrencesOfString:@"/" withString:@"_"]; imageURLCache = [imageURLCache stringByReplacingOccurrencesOfString:@" " withString:@"_"]; NSString *uniquePath = [tmp stringByAppendingPathComponent: imageURLCache]; if([[NSFileManager defaultManager] fileExistsAtPath: uniquePath]) { imageURLCache = [@"../tmp/" stringByAppendingString: imageURLCache]; [aContent replaceCharactersInRange: [aContent rangeOfString: imageURLBrut ] withString: imageURLCache]; } Article *article = [[Article alloc] initWithName:aName date:aDate url:aUrl category:aCategory author:aAuthor summary:aSummary content:aContent commentsNbr:aNbrComments commentsLink:aCommentsLink commentsRSS:@"" enclosure:aPermalink enclosure2:@"" enclosure3:@""]; [articles addObject:article]; article = nil; [article release]; } } sqlite3_finalize(compiledStatement); } sqlite3_close(database); } ` I have a lot of "Article" leaked and NSString matching with these using : [NSString stringWithUTF8String:(char *)sqlite3_column_text(compiledStatement, X)]; I tried a lot of different code I always have these leaks. Anyone has got an idea to help me?

  Read the article

• Recursive N-way merge/diff algorithm for directory trees?

  - by BobMcGee

  What algorithms or Java libraries are available to do N-way, recursive diff/merge of directories? I need to be able to generate a list of folder trees that have many identical files, and have subdirectories with many similar files. I want to be able to use 2-way merge operations to quickly remove as much redundancy as possible. Goals: Find pairs of directories that have many similar files between them. Generate short list of directory pairs that can be synchronized with 2-way merge to eliminate duplicates Should operate recursively (there may be nested duplicates of higher-level directories) Run time and storage should be O(n log n) in numbers of directories and files Should be able to use an embedded DB or page to disk for processing more files than fit in memory (100,000+). Optional: generate an ancestry and change-set between folders Optional: sort the merge operations by how many duplicates they can elliminate I know how to use hashes to find duplicate files in roughly O(n) space, but I'm at a loss for how to go from this to finding partially overlapping sets between folders and their children. EDIT: some clarification The tricky part is the difference between "exact same" contents (otherwise hashing file hashes would work) and "similar" (which will not). Basically, I want to feed this algorithm at a set of directories and have it return a set of 2-way merge operations I can perform in order to reduce duplicates as much as possible with as few conflicts possible. It's effectively constructing an ancestry tree showing which folders are derived from each other. The end goal is to let me incorporate a bunch of different folders into one common tree. For example, I may have a folder holding programming projects, and then copy some of its contents to another computer to work on it. Then I might back up and intermediate version to flash drive. Except I may have 8 or 10 different versions, with slightly different organizational structures or folder names. I need to be able to merge them one step at a time, so I can chose how to incorporate changes at each step of the way. This is actually more or less what I intend to do with my utility (bring together a bunch of scattered backups from different points in time). I figure if I can do it right I may as well release it as a small open source util. I think the same tricks might be useful for comparing XML trees though.

  Read the article

• JDOM Parser and Namespace how to get clean Content

  - by senzacionale

  MY xml: <?xml version="1.0"?> <company xmlns="http://www.xx.com/xx"> <staff> <firstname>yong</firstname> <lastname>mook kim</lastname> <nickname>mkyong</nickname> <salary>100000</salary> </staff> <staff> <firstname>low</firstname> <lastname>yin fong</lastname> <nickname>fong fong</nickname> <salary>200000</salary> </staff> </company> Reader in = new StringReader(message); Document document = (Document)saxBuilder.build(in); Element rootNode = document.getRootElement(); List<?> list = rootNode.getChildren("staff", Namespace.getNamespace("xmlns="http://www.infonova.com/MediationFeed"")); XMLOutputter outp = new XMLOutputter(); outp.setFormat(Format.getCompactFormat()); for (int ii = 0; ii < list.size(); ii++) { Element node = (Element)list.get(ii); StringWriter sw = new StringWriter(); outp.output(node.getContent(), sw); StringBuffer sb = sw.getBuffer(); String xml = sb.toString(); } but my xml object looks like this <firstname xmlns="http://www.xx.com/xx">yong</firstname> <lastname xmlns="http://www.xx.com/xx">mook kim</lastname> <nickname xmlns="http://www.xx.com/xx">mkyong</nickname> <salary xmlns="http://www.xx.com/xx">100000</salary> every elemnt has namespace. why this? i don't want namespace... I want the same output as is in xml example like <firstname>yong</firstname> <lastname>mook kim</lastname> <nickname>mkyong</nickname> <salary>100000</salary>

  Read the article

• Cannot access new product attributes in grid display

  - by russjman

  I added a couple new attribute to my products(a boolean "yes/no" fields). They are variables to enable/disable the price from displaying on the product detail page, and grid view. I managed to get it work on the product info page. But on product grid page I cant seem to access those variable. Specifically, the template i am working with is catalog/product/list.phtml. Ive tried adding them in the xml file like this layout/catalog.xml: <block type="catalog/product_list" name="product_list" template="catalog/product/list.phtml"> <action method="addAttribute"><name>DisplayPrice</name></action> <action method="addAttribute"><name>CustomOrder</name></action> </block> and I am trying to access the attributes like so in catalog/product/list.phtml: <?php echo $_product->getDisplayPriceName()? "Yes" : "No" ; echo $_product->getCustomOrderName()? "Yes" : "No" ;?> ive also added in the Mage config file app/code/core/Catalog/etc/config.xml: <frontend> <!---- stuff before this --> <product> <collection> <attributes> <name /> <url_key /> <price /> <special_price /> <custom_order /> <!--new attribute --> <display_price /> <!--new attribute --> <special_from_date /> <special_to_date /> <short_description /> <thumbnail /> <small_image /> <image_label /> <thumbnail_label /> <small_image_label /> <tax_class_id /> <status /> <news_from_date /> <news_to_date /> <created_at /> <updated_at /> </attributes> </collection> </product> </frontend> At this point im shooting in the dark. I dont know enough about the Magento backend to know where else i need to go or look. ANY feed back will be greatly appreciated. thanks in advance.

  Read the article

• Creating a spam list with a web crawler in python

  - by user313623

  Hey guys, I'm not trying to do anything malicious here, I just need to do some homework. I'm a fairly new programmer, I'm using python 3.0, and I having difficulty using recursion for problem-solving. I've been stuck on this question for quite a while. Here's the assignment: Write a recursive method spam(url, n) that takes a url of a web page as input and a non-negative integer n, collects all the email address contained in the web page and adds them to a global dictionary variable spam_dict, and then recursively calls itself on every http hyperlink contained in the web page. You will use a dictionary so only one copy of every email address is save; your dictionary will store (key,value) pairs (email, email). The recursive call should use the parameter n-1 instead of n. If n = 0, you should collect the email addresses but no recursive calls should be made. The parameter n is used to limit the recursion to at most depth n. You will need to use the solutions of the two above problems; you method spam() will call the methods links2() and emails() and possibly other functions as well. Notes: 1. running spam() directly will produce no output on the screen; to find your spam_dict, you will need to read the value of spam_dict, and you will also need to reset it to the empty dictionary before every run of spam. 2. Recall how global variables are used. Usage: spam_dict = {} spam('http://reed.cs.depaul.edu/lperkovic/csc242/test1.html',0) spam_dict.keys() dict_keys([]) spam_dict = {} spam('http://reed.cs.depaul.edu/lperkovic/csc242/test1.html',1) spam_dict.keys() dict_keys(['[email protected]', '[email protected]']) So far, I've written a function that traverses web pages and puts all the links in a nice little list, and what I wanted to do was call that functions. And why would I use recursion on a dictionary? And how? I don't understand how n ties into all of this. def links2(url): content = str(urlopen(url).read()) myparser = MyHTMLParser() myparser.feed(content) lst = myparser.get() mergelst = [] for link in lst: mergelst.append(urljoin(lst[0],link)) print(mergelst) Any input (except why spam is bad) would be greatly appreciated. Also, I realize that the above function could probably look better, if you have a way to do it, I'm all ears. However, all I need is the point is for the program to produce the proper output.

  Read the article

• Why does the rename() syscall prohibit moving a directory that I can't write to a different director

  - by Daniel Papasian

  I am trying to understand why this design decision was made with the rename() syscall in 4.2BSD. There's nothing I'm trying to solve here, just understand the rationale for the behavior itself. 4.2BSD saw the introduction of the rename() syscall for the purpose of allowing atomic renames/moves of files. From 4.3BSD-Reno/src/sys/ufs/ufs_vnops.c: /* * If ".." must be changed (ie the directory gets a new * parent) then the source directory must not be in the * directory heirarchy above the target, as this would * orphan everything below the source directory. Also * the user must have write permission in the source so * as to be able to change "..". We must repeat the call * to namei, as the parent directory is unlocked by the * call to checkpath(). */ if (oldparent != dp->i_number) newparent = dp->i_number; if (doingdirectory && newparent) { VOP_LOCK(fndp->ni_vp); error = ufs_access(fndp->ni_vp, VWRITE, tndp->ni_cred); VOP_UNLOCK(fndp->ni_vp); So clearly this check was added intentionally. My question is - why? Is this behavior supposed to be intuitive? The effect of this is that one cannot move a directory (located in a directory that one can write) that one cannot write to another directory that one can write to atomically. You can, however, create a new directory, move the links over (assuming one has read access to the directory), and then remove one's write bit on the directory. You just can't do so atomically. % cd /tmp % mkdir stackoverflow-question % cd stackoverflow-question % mkdir directory-1 % mkdir directory-2 % mkdir directory-1/directory-i-cant-write % echo "foo" > directory-1/directory-i-cant-write/contents % chmod 000 directory-1/directory-i-cant-write/contents % chmod 000 directory-1/directory-i-cant-write % mv directory-1/directory-i-cant-write directory-2 mv: rename directory-1/directory-i-cant-write to directory-2/directory-i-cant-write: Permission denied We now have a directory I can't write with contents I can't read that I can't move atomically. I can, however, achieve the same effect non-atomically by changing permissions, making the new directory, using ln to create the new links, and changing permissions. (Left as an exercise to the reader) . and .. are special cased already, so I don't particularly buy that it is intuitive that if I can't write a directory I can't "change .." which is what the source suggests. Is there any reason for this besides it being the perceived correct behavior by the author of the code? Is there anything bad that can happen if we let people atomically move directories (that they can't write) between directories that they can write?

  Read the article

• Java getInputStreat SocketTimeoutException instead of NoRouteToHostException

  - by Jon

  I have an odd issue happening when trying to open multiple Input Streams (in separate threads) on Linux (RHEL). The behaviour works as expected on windows. I am kicking off 3 threads to open https connections to 3 different servers. All three are invalid IP addresses (in this test case), so I expect an NoRouteToHostException for each of them. The first two return these as expected, and quite quickly. (see stack trace below) However the third (and 4th when I tested it that way) do NOT give a no route exception. They wait for ages, and then give a SocketTimeoutException (see other stack trace below). This takes ages to come back, and does not accurately express the connection issue. The offending line of code is: reader = new BufferedReader(new InputStreamReader(conn.getInputStream())); Has anyone seen something like this before? Are there multi-threading issues with sockets on REHL or some limit somewhere to how many can connect at once...or...something? Expected stack trace, as received for first two: java.net.NoRouteToHostException: No route to host at java.net.PlainSocketImpl.socketConnect(Native Method) at java.net.PlainSocketImpl.doConnect(PlainSocketImpl.java:333) at java.net.PlainSocketImpl.connectToAddress(PlainSocketImpl.java:195) at java.net.PlainSocketImpl.connect(PlainSocketImpl.java:182) at java.net.SocksSocketImpl.connect(SocksSocketImpl.java:366) at java.net.Socket.connect(Socket.java:529) at com.sun.net.ssl.internal.ssl.SSLSocketImpl.connect(SSLSocketImpl.java:559) at sun.net.NetworkClient.doConnect(NetworkClient.java:158) at sun.net.www.http.HttpClient.openServer(HttpClient.java:394) at sun.net.www.http.HttpClient.openServer(HttpClient.java:529) at sun.net.www.protocol.https.HttpsClient.(HttpsClient.java:272) at sun.net.www.protocol.https.HttpsClient.New(HttpsClient.java:329) at sun.net.www.protocol.https.AbstractDelegateHttpsURLConnection.getNewHttpClient(AbstractDelegateHttpsURLConnection.java:172) at sun.net.www.protocol.http.HttpURLConnection.plainConnect(HttpURLConnection.java:916) at sun.net.www.protocol.https.AbstractDelegateHttpsURLConnection.connect(AbstractDelegateHttpsURLConnection.java:158) at sun.net.www.protocol.http.HttpURLConnection.getInputStream(HttpURLConnection.java:1177) at sun.net.www.protocol.https.HttpsURLConnectionImpl.getInputStream(HttpsURLConnectionImpl.java:234) Unexpected stack trace, as received on 3rd: java.net.SocketTimeoutException: connect timed out at java.net.PlainSocketImpl.socketConnect(Native Method) at java.net.PlainSocketImpl.doConnect(PlainSocketImpl.java:333) at java.net.PlainSocketImpl.connectToAddress(PlainSocketImpl.java:195) at java.net.PlainSocketImpl.connect(PlainSocketImpl.java:182) at java.net.SocksSocketImpl.connect(SocksSocketImpl.java:366) at java.net.Socket.connect(Socket.java:529) at com.sun.net.ssl.internal.ssl.SSLSocketImpl.connect(SSLSocketImpl.java:559) at sun.net.NetworkClient.doConnect(NetworkClient.java:158) at sun.net.www.http.HttpClient.openServer(HttpClient.java:394) at sun.net.www.http.HttpClient.openServer(HttpClient.java:529) at sun.net.www.protocol.https.HttpsClient.(HttpsClient.java:272) at sun.net.www.protocol.https.HttpsClient.New(HttpsClient.java:329) at sun.net.www.protocol.https.AbstractDelegateHttpsURLConnection.getNewHttpClient(AbstractDelegateHttpsURLConnection.java:172) at sun.net.www.protocol.http.HttpURLConnection.plainConnect(HttpURLConnection.java:916) at sun.net.www.protocol.https.AbstractDelegateHttpsURLConnection.connect(AbstractDelegateHttpsURLConnection.java:158) at sun.net.www.protocol.http.HttpURLConnection.getInputStream(HttpURLConnection.java:1177) at sun.net.www.protocol.https.HttpsURLConnectionImpl.getInputStream(HttpsURLConnectionImpl.java:234)

  Read the article

• C# Reading and Writing a Char[] to and from a Byte[]

  - by Simon G

  Hi, I have a byte array of around 10,000 bytes which is basically a blob from delphi that contains char, string, double and arrays of various types. This need to be read in and updated via C#. I've created a very basic reader that gets the byte array from the db and converts the bytes to the relevant object type when accessing the property which works fine. My problem is when I try to write to a specific char[] item, it doesn't seem to update the byte array. I've created the following extensions for reading and writing: public static class CharExtension { public static byte ToByte( this char c ) { return Convert.ToByte( c ); } public static byte ToByte( this char c, int position, byte[] blob ) { byte b = c.ToByte(); blob[position] = b; return b; } } public static class CharArrayExtension { public static byte[] ToByteArray( this char[] c ) { byte[] b = new byte[c.Length]; for ( int i = 1; i < c.Length; i++ ) { b[i] = c[i].ToByte(); } return b; } public static byte[] ToByteArray( this char[] c, int positon, int length, byte[] blob ) { byte[] b = c.ToByteArray(); Array.Copy( b, 0, blob, positon, length ); return b; } } public static class ByteExtension { public static char ToChar( this byte[] b, int position ) { return Convert.ToChar( b[position] ); } } public static class ByteArrayExtension { public static char[] ToCharArray( this byte[] b, int position, int length ) { char[] c = new char[length]; for ( int i = 0; i < length; i++ ) { c[i] = b.ToChar( position ); position += 1; } return c; } } to read and write chars and char arrays my code looks like: Byte[] _Blob; // set from a db field public char ubin { get { return _tariffBlob.ToChar( 14 ); } set { value.ToByte( 14, _Blob ); } } public char[] usercaplas { get { return _tariffBlob.ToCharArray( 2035, 10 ); } set { value.ToByteArray( 2035, 10, _Blob ); } } So to write to the objects I can do: ubin = 'C'; // this will update the byte[] usercaplas = new char[10] { 'A', 'B', etc. }; // this will update the byte[] usercaplas[3] = 'C'; // this does not update the byte[] I know the reason is that the setter property is not being called but I want to know is there a way around this using code similar to what I already have? I know a possible solution is to use a private variable called _usercaplas that I set and update as needed however as the byte array is nearly 10,000 bytes in length the class is already long and I would like a simpler approach as to reduce the overall code length and complexity. Thank

  Read the article

• Saving image to database as varbinary, arraylength (part 2)

  - by Thomas Schoof

  This is a followup to my previous question, which got solved (thank you for that) but now I am stuck at another error. I'm trying to save an image in my database (called 'Afbeelding'), for that I made a table which excists of: id: int souce: varbinary(max) I then created a wcf service to save an 'Afbeelding' to the database. private static DataClassesDataContext dc = new DataClassesDataContext(); [OperationContract] public void setAfbeelding(Afbeelding a) { //Afbeelding a = new Afbeelding(); //a.id = 1; //a.source = new Binary(bytes); dc.Afbeeldings.InsertOnSubmit(a); dc.SubmitChanges(); } I then put a reference to the service in my project and when I press the button I try to save it to the datbase. private void btnUpload_Click(object sender, RoutedEventArgs e) { Afbeelding a = new Afbeelding(); OpenFileDialog openFileDialog = new OpenFileDialog(); openFileDialog.Filter = "JPEG files|*.jpg"; if (openFileDialog.ShowDialog() == true) { //string imagePath = openFileDialog.File.Name; //FileStream fileStream = new FileStream(imagePath, FileMode.Open, FileAccess.Read); //byte[] buffer = new byte[fileStream.Length]; //fileStream.Read(buffer, 0, (int)fileStream.Length); //fileStream.Close(); Stream stream = (Stream)openFileDialog.File.OpenRead(); Byte[] bytes = new Byte[stream.Length]; stream.Read(bytes, 0, (int)stream.Length); string fileName = openFileDialog.File.Name; a.id = 1; a.source = new Binary { Bytes = bytes }; } EditAfbeeldingServiceClient client = new EditAfbeeldingServiceClient(); client.setAfbeeldingCompleted +=new EventHandler<System.ComponentModel.AsyncCompletedEventArgs>(client_setAfbeeldingCompleted); client.setAfbeeldingAsync(a); } void client_setAfbeeldingCompleted(object sender, System.ComponentModel.AsyncCompletedEventArgs e) { if (e.Error != null) txtEmail.Text = e.Error.ToString(); else MessageBox.Show("WIN"); } However, when I do this, I get the following error: System.ServiceModel.FaultException: The formatter threw an exception while trying to deserialize the message: There was an error while trying to deserialize parameter :a. The InnerException message was 'There was an error deserializing the object of type OndernemersAward.Web.Afbeelding. The maximum array length quota (16384) has been exceeded while reading XML data. This quota may be increased by changing the MaxArrayLength property on the XmlDictionaryReaderQuotas object used when creating the XML reader.'. Please see InnerException for more details. at System.ServiceModel.Channels.ServiceChannel.HandleReply(ProxyOperationRuntime operation, ProxyRpc& rpc) at System.ServiceModel.Channels.ServiceChannel.EndCall(String action, Object[] outs, IAsyncResult result) at System.ServiceModel.ClientBase`1.ChannelBase`1.EndInvoke(String methodName, Object[] args, IAsyncResult result) atOndernemersAward.EditAfbeeldingServiceReference.EditAfbeeldingServiceClient.EditAfbeeldingServiceClientChannel.EndsetAfbeelding(IAsyncResult result) at OndernemersAward.EditAfbeeldingServiceReference.EditAfbeeldingServiceClient.OndernemersAward.EditAfbeeldingServiceReference.EditAfbeeldingService.EndsetAfbeelding(IAsyncResult result) at OndernemersAward.EditAfbeeldingServiceReference.EditAfbeeldingServiceClient.OnEndsetAfbeelding(IAsyncResult result) at System.ServiceModel.ClientBase`1.OnAsyncCallCompleted(IAsyncResult result) I'm not sure what's causing this but I think it has something to do with the way I write the image to the database? (The array length is too big big, I don't really know how to change it) Thank you for your help, Thomas

  Read the article

• How do we, as a community, help encourage programming in public schools? (Or state Schools for the U

  - by NoMoreZealots

  PRIMARY MOTIVATION My office gets involved with the "First Robotics" competitions and one thing that lingers year to year is the students typically have no preparation for doing even simple programming as part of the public schools system. While the science classes provide some basic grasp of mechanical and electrical concepts, by in large computer programming gets no coverage from the curriculum. (This my be different in other areas of the country/world.) What makes it worse is there is only a short period of time you have to prepare the student's and help them design the robot. Talking to some professors from local colleges, it's a problem because you can't assume even the most basic understanding for freshman CS majors. Languages like Python, Lua and BASIC are simple enough for at least high school level students, if not younger. SCOPE So how do you get public schools to support a programming, at least to the level of "Try it in BASIC" examples that used to be at the end of a chapter in my Algebra book? At least enough to prepare them for event's such as the FIRST Robotic competitions. Which the primary objectives are to teach problem solving and team work, and to possible foster an interest in Math, Science and Engineering in general. (Not force feed to them, as some people her seem to be implying.) Edit: Why teach kids: (Since 2000 CS enrollment in US colleges has decreased by 70% while college enrollment has increased, this is a PROBLEM.) Saying there is no value in teaching someone programming in Jr./High school because they might think "they know programming." Is like saying there's no value in teaching High school science and physics, because they might decide they "know physics." Leading to abuse like: "I passed a high school physics class, I'm going to develop a Unified Quantum Gravitational Theory." Better Prepared students are better students. Instead it would allows college programs to raise the bar on the entry level courses, allowing students to be weeded out based on their understanding of more advanced material. Plus people who did poorly in that in topic in High school aren't as likely to say "I think there's money in computer's so I'll computer science." Plus if people take it in high school and decide THEN that it's not for them, it's better than them wasting their money to PAY a college to figure that out. The result is that people who take the degree are more likely to succeed and be there for the RIGHT reasons. (i.e. It's what they REALLY want to do. And that's REALLY the key to being good at anything.) Programming is like anything else, the more practice and genuine interest you have the better you get. If you start them later, they get less practice. The earlier give them the opportunity to start, the more practice they will get. All other things equal, the more practice the better the programmer.

  Read the article

• Exception when indexing text documents with Lucene, using SnowballAnalyzer for cleaning up

  - by Julia

  Hello!!! I am indexing the documents with Lucene and am trying to apply the SnowballAnalyzer for punctuation and stopword removal from text .. I keep getting the following error :( IllegalAccessError: tried to access method org.apache.lucene.analysis.Tokenizer.(Ljava/io/Reader;)V from class org.apache.lucene.analysis.snowball.SnowballAnalyzer Here is the code, I would very much appreciate help!!!! I am new with this.. public class Indexer { private Indexer(){}; private String[] stopWords = {....}; private String indexName; private IndexWriter iWriter; private static String FILES_TO_INDEX = "/Users/ssi/forindexing"; public static void main(String[] args) throws Exception { Indexer m = new Indexer(); m.index("./newindex"); } public void index(String indexName) throws Exception { this.indexName = indexName; final File docDir = new File(FILES_TO_INDEX); if(!docDir.exists() || !docDir.canRead()){ System.err.println("Something wrong... " + docDir.getPath()); System.exit(1); } Date start = new Date(); PerFieldAnalyzerWrapper analyzers = new PerFieldAnalyzerWrapper(new SimpleAnalyzer()); analyzers.addAnalyzer("text", new SnowballAnalyzer("English", stopWords)); Directory directory = FSDirectory.open(new File(this.indexName)); IndexWriter.MaxFieldLength maxLength = IndexWriter.MaxFieldLength.UNLIMITED; iWriter = new IndexWriter(directory, analyzers, true, maxLength); System.out.println("Indexing to dir..........." + indexName); if(docDir.isDirectory()){ File[] files = docDir.listFiles(); if(files != null){ for (int i = 0; i < files.length; i++) { try { indexDocument(files[i]); }catch (FileNotFoundException fnfe){ fnfe.printStackTrace(); } } } } System.out.println("Optimizing...... "); iWriter.optimize(); iWriter.close(); Date end = new Date(); System.out.println("Time to index was" + (end.getTime()-start.getTime()) + "miliseconds"); } private void indexDocument(File someDoc) throws IOException { Document doc = new Document(); Field name = new Field("name", someDoc.getName(), Field.Store.YES, Field.Index.ANALYZED); Field text = new Field("text", new FileReader(someDoc), Field.TermVector.WITH_POSITIONS_OFFSETS); doc.add(name); doc.add(text); iWriter.addDocument(doc); } }

  Read the article

• Class hierarchy problem (with generic's variance!)

  - by devoured elysium

  The problem: class StatesChain : IState, IHasStateList { private TasksChain tasks = new TasksChain(); ... public IList<IState> States { get { return _taskChain.Tasks; } } IList<ITask> IHasTasksCollection.Tasks { get { return _taskChain.Tasks; } <-- ERROR! You can't do this in C#! I want to return an IList<ITask> from an IList<IStates>. } } Assuming the IList returned will be read-only, I know that what I'm trying to achieve is safe (or is it not?). Is there any way I can accomplish what I'm trying? I wouldn't want to try to implement myself the TasksChain algorithm (again!), as it would be error prone and would lead to code duplication. Maybe I could just define an abstract Chain and then implement both TasksChain and StatesChain from there? Or maybe implementing a Chain<T> class? How would you approach this situation? The Details: I have defined an ITask interface: public interface ITask { bool Run(); ITask FailureTask { get; } } and a IState interface that inherits from ITask: public interface IState : ITask { IState FailureState { get; } } I have also defined an IHasTasksList interface: interface IHasTasksList { List<Tasks> Tasks { get; } } and an IHasStatesList: interface IHasTasksList { List<Tasks> States { get; } } Now, I have defined a TasksChain, that is a class that has some code logic that will manipulate a chain of tasks (beware that TasksChain is itself a kind of ITask!): class TasksChain : ITask, IHasTasksList { IList<ITask> tasks = new List<ITask>(); ... public List<ITask> Tasks { get { return _tasks; } } ... } I am implementing a State the following way: public class State : IState { private readonly TaskChain _taskChain = new TaskChain(); public State(Precondition precondition, Execution execution) { _taskChain.Tasks.Add(precondition); _taskChain.Tasks.Add(execution); } public bool Run() { return _taskChain.Run(); } public IState FailureState { get { return (IState)_taskChain.Tasks[0].FailureTask; } } ITask ITask.FailureTask { get { return FailureState; } } } which, as you can see, makes use of explicit interface implementations to "hide" FailureTask and instead show FailureState property. The problem comes from the fact that I also want to define a StatesChain, that inherits both from IState and IHasStateList (and that also imples ITask and IHasTaskList, implemented as explicit interfaces) and I want it to also hide IHasTaskList's Tasks and only show IHasStateList's States. (What is contained in "The problem" section should really be after this, but I thought puting it first would be way more reader friendly). (pff..long text) Thanks!

  Read the article

• How to maxmise the largest contiguous block of memory in the Large Object Heap

  - by Unsliced

  The situation is that I am making a WCF call to a remote server which is returns an XML document as a string. Most of the time this return value is a few K, sometimes a few dozen K, very occasionally a few hundred K, but very rarely it could be several megabytes (first problem is that there is no way for me to know). It's these rare occasions that are causing grief. I get a stack trace that starts: System.OutOfMemoryException: Exception of type 'System.OutOfMemoryException' was thrown. at System.Xml.BufferBuilder.AddBuffer() at System.Xml.BufferBuilder.AppendHelper(Char* pSource, Int32 count) at System.Xml.BufferBuilder.Append(Char[] value, Int32 start, Int32 count) at System.Xml.XmlTextReaderImpl.ParseText() at System.Xml.XmlTextReaderImpl.ParseElementContent() at System.Xml.XmlTextReaderImpl.Read() at System.Xml.XmlTextReader.Read() at System.Xml.XmlReader.ReadElementString() at Microsoft.Xml.Serialization.GeneratedAssembly.XmlSerializationReaderMDRQuery.Read2_getMarketDataResponse() at Microsoft.Xml.Serialization.GeneratedAssembly.ArrayOfObjectSerializer2.Deserialize(XmlSerializationReader reader) at System.Xml.Serialization.XmlSerializer.Deserialize(XmlReader xmlReader, String encodingStyle, XmlDeserializationEvents events) at System.Xml.Serialization.XmlSerializer.Deserialize(XmlReader xmlReader, String encodingStyle) at System.Web.Services.Protocols.SoapHttpClientProtocol.ReadResponse(SoapClientMessage message, WebResponse response, Stream responseStream, Boolean asyncCall) at System.Web.Services.Protocols.SoapHttpClientProtocol.Invoke(String methodName, Object[] parameters) I've read around and it is because the Large Object Heap is just getting too fragmented, so even preceding the call with a quick check to StringBuilder.EnsureCapacity just causes the OutOfMemoryException to be thrown earlier (and because I'm guessing at what's needed, it might not actually need that much so my check is causing more problems than it is solving). Some opinions are that there's not much I can do about it. Some of the questions I've asked myself: Use less memory - have you checked for leaks? Yes. The memory usage goes up and down, but there's no fundamental growth that guarantees this to happen. Some of the times it fails, it succeeded at that stage previously. Transfer smaller amounts Not an option, this is a third party web service over which I have no control (or at least it would take a long time to resolve, in the meantime I still have a problem) Can you do something to the LOH to make it less likely to fail? ... now this is most fruitful course. It's a 32-bit process (it has to be for various political, technical and boring reasons) but there's normally hundreds of meg free (multiples of the largest amount for which we've seen failures). Can we monitor the LOH? Using perfmon I can track the size of the heaps, but I don't think there's a way to monitor the largest available contiguous block of memory. Question is: any advice or suggestions for things to try?

  Read the article

• I can't Open my excel file in c#

  - by Ruben Guico

  Hi, Below is my code, i tried to open my excel file in my c# application but the program give's me an error message "Cannot Access "my excel.xls". But when I specify the file path in my string path variable it works, the problem is I need to get the file path from an openFileDialog. using System; using System.IO; using System.Collections.Generic; using System.Text; using System.Data; using System.Windows.Forms; using System.Data.OleDb; using System.Reflection; using MOIE = Microsoft.Office.Interop.Excel; using OFFICE = Microsoft.Office.Core; namespace EmpUploader { public class ExcelCon { private OleDbDataReader reader = null; private OleDbCommand excelCommand = new OleDbCommand(); private OleDbDataAdapter adapter = new OleDbDataAdapter(); private DataTable excelData = new DataTable(); private MOIE.ApplicationClass objExcel = new MOIE.ApplicationClass(); private MOIE.Workbook wb = null; private string myConn = ""; private string strSQL = ""; private string err = ""; private string path2 = ""; private int sheetCount = 0; private OleDbConnection Con = new OleDbConnection(""); #region "excel interop prarameters" private static object xl_missing = Type.Missing; private static object xl_true = true; private static object xl_false = false; private object xl_update_links = xl_missing; private object xl_read_only = xl_missing; private object xl_format = xl_missing; private object xl_password = xl_missing; private object xl_write_res_password = xl_missing; private object xl_ignore_read_only = xl_missing; private object xl_origin = xl_missing; private object xl_delimiter = xl_missing; private object xl_editable = xl_missing; private object xl_notify = xl_missing; private object xl_converter = xl_missing; private object xl_add_to_mru = xl_missing; private object xl_local = xl_missing; private object xl_corrupt_load = xl_missing; #endregion } //MY CODE FOR OPENING THE EXCEL //note that my file path came from an openfiledialog public void InitializeConnection(string path) { //connection string for excel myConn = @"Provider=Microsoft.Jet.OLEDB.4.0; Data Source=" + path + "; Extended Properties =Excel 8.0"; Con.ConnectionString = myConn; Con.Open(); //this is the sample specified path that worked when i test my application //path = @"C:\shinetsu p5 emp list.xls"; objExcel.Visible = false; wb = objExcel.Workbooks.Open(path, xl_update_links, xl_read_only, xl_format, xl_password, xl_write_res_password, xl_ignore_read_only, xl_origin, xl_delimiter, xl_editable, xl_notify, xl_converter, xl_add_to_mru, xl_local, xl_corrupt_load); sheetCount = wb.Worksheets.Count; } }

  Read the article

• How do I add a trailing slash for Django MPTT-based categorization app?

  - by Patrick Beeson

  I'm using Django-MPTT to develop a categorization app for my Django project. But I can't seem to get the regex pattern for adding a trailing slash that doesn't also break on child categories. Here's an example URL: http://mydjangoapp.com/categories/parentcat/childcat/ I'd like to be able to use http://mydjangoapp.com/categories/parentcat and have it redirect to the trailing slash version. The same should apply to http://mydjangoapp.com/categories/parentcat/childcat (it should redirect to http://mydjangoapp.com/categories/parentcat/childcat/). Here's my urls.py: from django.conf.urls.defaults import patterns, include, url from django.views.decorators.cache import cache_page from storefront.categories.models import Category from storefront.categories.views import SimpleCategoryView urlpatterns = patterns('', url(r'^(?P<full_slug>[-\w/]+)', cache_page(SimpleCategoryView.as_view(), 60 * 15), name='category_view'), ) And here is my view: from django.core.exceptions import ImproperlyConfigured from django.core.urlresolvers import reverse from django.views.generic import TemplateView, DetailView from django.views.generic.detail import SingleObjectTemplateResponseMixin, SingleObjectMixin from django.utils.translation import ugettext as _ from django.contrib.syndication.views import Feed from storefront.categories.models import Category class SimpleCategoryView(TemplateView): def get_category(self): return Category.objects.get(full_slug=self.kwargs['full_slug']) def get_context_data(self, **kwargs): context = super(SimpleCategoryView, self).get_context_data(**kwargs) context["category"] = self.get_category() return context def get_template_names(self): if self.get_category().template_name: return [self.get_category().template_name] else: return ['categories/category_detail.html'] And finally, my model: from django.db import models from mptt.models import MPTTModel from mptt.fields import TreeForeignKey class CategoryManager(models.Manager): def get(self, **kwargs): defaults = {} defaults.update(kwargs) if 'full_slug' in defaults: if defaults['full_slug'] and defaults['full_slug'][-1] != "/": defaults['full_slug'] += "/" return super(CategoryManager, self).get(**defaults) class Category(MPTTModel): title = models.CharField(max_length=255) description = models.TextField(blank=True, help_text='Please use <a href="http://daringfireball.net/projects/markdown/syntax">Markdown syntax</a> for all text-formatting and links. No HTML is allowed.') slug = models.SlugField(help_text='Prepopulates from title field.') full_slug = models.CharField(max_length=255, blank=True) template_name = models.CharField(max_length=70, blank=True, help_text="Example: 'categories/category_parent.html'. If this isn't provided, the system will use 'categories/category_detail.html'. Use 'categories/category_parent.html' for all parent categories and 'categories/category_child.html' for all child categories.") parent = TreeForeignKey('self', null=True, blank=True, related_name='children') objects = CategoryManager() class Meta: verbose_name = 'category' verbose_name_plural = 'categories' def save(self, *args, **kwargs): orig_full_slug = self.full_slug if self.parent: self.full_slug = "%s%s/" % (self.parent.full_slug, self.slug) else: self.full_slug = "%s/" % self.slug obj = super(Category, self).save(*args, **kwargs) if orig_full_slug != self.full_slug: for child in self.get_children(): child.save() return obj def available_product_set(self): """ Returns available, prioritized products for a category """ from storefront.apparel.models import Product return self.product_set.filter(is_available=True).order_by('-priority') def __unicode__(self): return "%s (%s)" % (self.title, self.full_slug) def get_absolute_url(self): return '/categories/%s' % (self.full_slug)

  Read the article

• Android USB Host Communication

  - by Kip Russell

  I'm working on a project that utilizes the USB Host capabilities in Android 3.2. I'm suffering from a deplorable lack of knowledge and talent regarding USB/Serial communication in general. I'm also unable to find any good example code for what I need to do. I need to read from a USB Communication Device. Ex: When I connect via Putty (on my PC) I enter: >GO And the device starts spewing out data for me. Pitch/Roll/Temp/Checksum. Ex: $R1.217P-0.986T26.3*60 $R1.217P-0.986T26.3*60 $R1.217P-0.987T26.3*61 $R1.217P-0.986T26.3*60 $R1.217P-0.985T26.3*63 I can send the initial 'GO' command from the Android device at which time I receive an echo of 'GO'. Then nothing else on any subsequent reads. How can I: 1) Send the 'go' command. 2) Read in the stream of data that results. The USB device I'm working with has the following interfaces (endpoints). Device Class: Communication Device (0x2) Interfaces: Interface #0 Class: Communication Device (0x2) Endpoint #0 Direction: Inbound (0x80) Type: Intrrupt (0x3) Poll Interval: 255 Max Packet Size: 32 Attributes: 000000011 Interface #1 Class: Communication Device Class (CDC) (0xa) Endpoint #0 Address: 129 Number: 1 Direction: Inbound (0x80) Type: Bulk (0x2) Poll Interval (0) Max Packet Size: 32 Attributes: 000000010 Endpoint #1 Address: 2 Number: 2 Direction: Outbound (0x0) Type: Bulk (0x2) Poll Interval (0) Max Packet Size: 32 Attributes: 000000010 I'm able to deal with permission, connect to the device, find the correct interface and assign the endpoints. I'm just having trouble figuring out which technique to use to send the initial command read the ensuing data. I'm tried different combinations of bulkTransfer and controlTransfer with no luck. Thanks. I'm using interface#1 as seen below: public AcmDevice(UsbDeviceConnection usbDeviceConnection, UsbInterface usbInterface) { Preconditions.checkState(usbDeviceConnection.claimInterface(usbInterface, true)); this.usbDeviceConnection = usbDeviceConnection; UsbEndpoint epOut = null; UsbEndpoint epIn = null; // look for our bulk endpoints for (int i = 0; i < usbInterface.getEndpointCount(); i++) { UsbEndpoint ep = usbInterface.getEndpoint(i); Log.d(TAG, "EP " + i + ": " + ep.getType()); if (ep.getType() == UsbConstants.USB_ENDPOINT_XFER_BULK) { if (ep.getDirection() == UsbConstants.USB_DIR_OUT) { epOut = ep; } else if (ep.getDirection() == UsbConstants.USB_DIR_IN) { epIn = ep; } } } if (epOut == null || epIn == null) { throw new IllegalArgumentException("Not all endpoints found."); } AcmReader acmReader = new AcmReader(usbDeviceConnection, epIn); AcmWriter acmWriter = new AcmWriter(usbDeviceConnection, epOut); reader = new BufferedReader(acmReader); writer = new BufferedWriter(acmWriter); }

  Read the article

• Realtime Twitter Replies?

  - by ejunker

  I have created Twitter bots for many geographic locations. I want to allow users to @-reply to the Twitter bot with commands and then have the bot respond with the results. I would like to have the bot reply to the user as quickly as possible (realtime). Apparently, Twitter used to have an XMPP/Jabber interface that would provide this type of realtime feed of replies but it was shut down. As I see it my options are to use one of the following: REST API This would involve polling every X minutes for each bot. The problem with this is that it is not realtime and each Twitter account would have to be polled. Search API The search API does allow specifying a "-to" parameter in the search and replies to all bots could be aggregated in a search such as "-to bot1 OR -to bot2...". Though if you have hundreds of bots then the search string would get very long and probably exceed the maximum length of a GET request. Streaming API The streaming API looks very promising as it provides realtime results. The API allows you to specify a follow and track parameters. follow is not useful as the bot does not know who will be sending it commands. track allows you to specify keywords to track. This could possibly work by creating a daemon process that connects to the Streaming API and tracks all references to the bot's names. Once again since there are lots of bots to track the length and complexity of the query may be an issue. Another idea would be to track a special hashtag such as #botcommand and then a user could send a command using this syntax @bot1 weather #botcommand. Then by using the Streaming API to track all references to #botcommand would give you a realtime stream of all the commands. Further parsing could then be done to determine which bot to send the command to. Third-party service Are there any third-party companies that have access to the Twitter firehouse and offer realtime data? I haven't investigated these, but here are a few that I have found: Gnip Tweet.IM excla.im TwitterSpy - seems to use polling, not realtime I'm leaning towards using the Streaming API. Is there a better way to get near realtime @-replies for many (hundreds) of Twitter accounts?

  Read the article

• How to apply or chain multiple matching templates in XSLT?

  - by Ignatius

  I am working on a stylesheet employing many templates with match attributes: <xsl:template match="//one" priority="0.7"> <xsl:param name="input" select="."/> <xsl:value-of select="util:uppercase($input)"/> <xsl:next-match /> </xsl:template> <xsl:template match="/stuff/one"> <xsl:param name="input" select="."/> <xsl:value-of select="util:add-period($input)"/> </xsl:template> <xsl:function name="util:uppercase"> <xsl:param name="input"/> <xsl:value-of select="upper-case($input)"/> </xsl:function> <xsl:function name="util:add-period"> <xsl:param name="input"/> <xsl:value-of select="concat($input,'.')"/> </xsl:function> What I would like to do is be able to 'chain' the two functions above, so that an input of 'string' would be rendered in the output as 'STRING.' (with the period.) I would like to do this in such a way that doesn't require knowledge of other templates in any other template. So, for instance, I would like to be able to add a "util:add-colon" method without having to open up the hood and monkey with the existing templates. I was playing around with the <xsl:next-match/> instruction to accomplish this. Adding it to the first template above does of course invoke both util:uppercase and util:add-period, but the output is an aggregation of each template output (i.e. 'STRINGstring.') It seems like there should be an elegant way to chain any number of templates together using something like <xsl:next-match/>, but have the output of each template feed the input of the next one in the chain. Am I overlooking something obvious?

  Read the article

< Previous Page | 176 177 178 179 180 181 182 183 184 185 186 187  | Next Page >