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  • Help with iphone dev - beyond bounds error

    - by dusk
    I'm just learning iphone development, so please forgive me for what is probably a beginner error. I've searched around and haven't found anything specific to my problem, so hopefully it is an easy fix. The book has examples of building a table from data hard coded via an array. Unfortunately it never really tells you how to get data from a URL, so I've had to look that up and that is where my problems show up. When I debug in xcode, it seems like the count is correct, so I don't understand why it is going out of bounds? This is the error message: 2010-05-03 12:50:42.705 Simple Table[3310:20b] *** Terminating app due to uncaught exception 'NSRangeException', reason: '*** -[NSCFArray objectAtIndex:]: index (1) beyond bounds (0)' My URL returns the following string: first,second,third,fourth And here is the iphone code with the book's working example commented out #import "Simple_TableViewController.h" @implementation Simple_TableViewController @synthesize listData; - (void)viewDidLoad { /* //working code from book NSArray *array = [[NSArray alloc] initWithObjects:@"Sleepy", @"Sneezy", @"Bashful", @"Bashful", @"Happy", @"Doc", @"Grumpy", @"Thorin", @"Dorin", @"Norin", @"Ori", @"Balin", @"Dwalin", @"Fili", @"Kili", @"Oin", @"Gloin", @"Bifur", @"Bofur", @"Bombur", nil]; self.listData = array; [array release]; */ //code from interwebz that crashes NSString *urlstr = [[NSString alloc] initWithFormat:@"http://www.mysite.com/folder/iphone-test.php"]; NSURL *url = [[NSURL alloc] initWithString:urlstr]; NSString *ans = [NSString stringWithContentsOfURL:url]; NSArray *listItems = [ans componentsSeparatedByString:@","]; self.listData = listItems; [urlstr release]; [url release]; [ans release]; [listItems release]; [super viewDidLoad]; } - (void)didReceiveMemoryWarning { // Releases the view if it doesn't have a superview. [super didReceiveMemoryWarning]; // Release any cached data, images, etc that aren't in use. } - (void)viewDidUnload { // Release any retained subviews of the main view. // e.g. self.myOutlet = nil; self.listData = nil; [super viewDidUnload]; } - (void)dealloc { [listData release]; [super dealloc]; } #pragma mark - #pragma mark Table View Data Source Methods - (NSInteger)tableView:(UITableView *)tableView numberOfRowsInSection:(NSInteger)section { return [self.listData count]; } - (UITableViewCell *)tableView:(UITableView *)tableView cellForRowAtIndexPath:(NSIndexPath *)indexPath { static NSString *SimpleTableIdentifier = @"SimpleTableIdentifier"; UITableViewCell *cell = [tableView dequeueReusableCellWithIdentifier:SimpleTableIdentifier]; if (cell == nil) { cell = [[[UITableViewCell alloc] initWithStyle:UITableViewCellStyleDefault reuseIdentifier:SimpleTableIdentifier] autorelease]; } NSUInteger row = [indexPath row]; cell.textLabel.text = [listData objectAtIndex:row]; return cell; } @end

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  • When using delegates, need better way to do sequential processing

    - by Padawan
    I have a class WebServiceCaller that uses NSURLConnection to make asynchronous calls to a web service. The class provides a delegate property and when the web service call is done, it calls a method webServiceDoneWithXXX on the delegate. There are several web service methods that can be called, two of which are say GetSummary and GetList. The classes that use WebServiceCaller initially need both the summary and list so they are written like this: -(void)getAllData { [webServiceCaller getSummary]; } -(void)webServiceDoneWithGetSummary { [webServiceCaller getList]; } -(void)webServiceDoneWithGetList { ... } This works but there are at least two problems: The calls are split across delegate methods so it's hard to see the sequence at a glance but more important it's hard to control or modify the sequence. Sometimes I want to call just GetSummary and not also GetList so I would then have to use an ugly class-level state variable that tells webServiceDoneWithGetSummary whether to call GetList or not. Assume that GetList cannot be done until GetSummary completes and returns some data which is used as input to GetList. Is there a better way to handle this and still get asynchronous calls? Update based on Matt Long's answer: Using notifications instead of a delegate, it looks like I can solve problem #2 by setting a different selector depending on whether I want the full sequence (GetSummary+GetList) or just GetSummary. Both observers would still use the same notification name when calling GetSummary. I would have to write two separate methods to handle GetSummaryDone instead of using a single delegate method (where I would have needed some class-level variable to tell whether to then call GetList). -(void)getAllData { [[NSNotificationCenter defaultCenter] addObserver:self              selector:@selector(getSummaryDoneAndCallGetList:)                  name:kGetSummaryDidFinish object:nil];     [webServiceCaller getSummary]; } -(void)getSummaryDoneAndCallGetList { [NSNotificationCenter removeObserver] //process summary data [[NSNotificationCenter defaultCenter] addObserver:self              selector:@selector(getListDone:)                  name:kGetListDidFinish object:nil];     [webServiceCaller getList]; } -(void)getListDone { [NSNotificationCenter removeObserver] //process list data } -(void)getJustSummaryData { [[NSNotificationCenter defaultCenter] addObserver:self              selector:@selector(getJustSummaryDone:) //different selector but                  name:kGetSummaryDidFinish object:nil]; //same notification name     [webServiceCaller getSummary]; } -(void)getJustSummaryDone { [NSNotificationCenter removeObserver] //process summary data } I haven't actually tried this yet. It seems better than having state variables and if-then statements but you have to write more methods. I still don't see a solution for problem 1.

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  • PHP to Mesh 2 PDF'S Together or not?

    - by Justin
    I have an already pre-designed PDF, and I would like to fill the PDF with some database information. So I'm curious if I should save the PDF into JPG's and render them out with the data on top of the image and re-create a PDF. Or is there a way to use the PDF already, and print data into the PDF that is already made? I am trying to figure out the best solution to generating this type of PDF. All thoughts would be greatly appreciated!

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  • Zend_DB_Table Update problem

    - by davykiash
    Am trying to construct a simple update query in my model class Model_DbTable_Account extends Zend_Db_Table_Abstract { protected $_name = 'accounts'; public function activateaccount($activationcode) { $data = array( 'accounts_status' => 'active', ); $this->update($data, 'accounts_activationkey = ' . $activationcode); } However I get an SQLSTATE[42S22]: Column not found: 1054 Unknown column 'my activation code value' in 'where clause' error. What am I missing in Zend_Table update construct?

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  • Read XML using Sencha

    - by user580950
    I am about to develop a application using Sencha touch. The issue i am facing right now is Sencha code should read the following XML ( "data.xml" and display News, Articles...), any expert that can help here please ? <ns2:categories> <category> <catId>96</catId> <title>News</title> </category> <category> <catId>97</catId> <title>Articles</title> </category> </ns2:categories> and when i click on News as an example should read that particular "recordId" element in "data_read.xml" and display "origUrl","title","data" .the data_read.xml looks like below.. <ns2:records> <record> <recordId>96</recordId> <title>123 Lifted</title> <author>|</author> <published>2010-01-20T14:36:00.000-08:00</published> <origUrl> http://www.abc.com/</origUrl> <numComments>0</numComments> <data> <![CDATA[<p>According to a report on sd asdas das asdasd asdasd hjjasd .</p> <p> </p> <p>This is a landmark vote, and a harbinger of change for this extremely traditional area that also has banned the use of metal r bolt.</p> <p> </p> <p>Check out: abc.com and xyz .com for more information.</p> <p class="modifydate">Last Updated (Wednesday, 20 January 2010 22:36)</p>]]> </data> </record> </ns2:records> IS this possible in Sencha ? Thanks for your help in advance

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  • Java RegExp ViewState

    - by CDSO1
    I am porting some functionality from a C++ application to java. This involves reading non-modifiable data files that contain regular expressions. A lot of the data files contain regular expressions that look similar to the following: (?<=id="VIEWSTATE".*?value=").*?(?=") These regular expressions produce the following error: "Look-behind group does not have an obvious maximum length near index XX" In C++ the engine being used supported these expressions. Is there another form of regexp that can produce the same result that can be generated using expressions like my example as input?

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  • how do I convert if else to one line if else?

    - by roozbeh heydari
    how do i convert follow code to one line if else if (data.BaseCompareId == 2) report.Load(Server.MapPath("~/Content/StimulReports/MonthGroup.mrt")); else report.Load(Server.MapPath("~/Content/StimulReports/YearGroup.mrt")); i try this code but did not work data.BaseCompareId == 2 ? report.Load(Server.MapPath("~/Content/StimulReports/MonthGroup.mrt")) : report.Load(Server.MapPath("~/Content/StimulReports/YearGroup.mrt"));

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  • HTTP Error: 413 Request Entity Too Large

    - by Torben Gundtofte-Bruun
    What I have: I have an iPhone app that sends HTTP POST requests (XML format) to a web service written in PHP. This is on a hosted virtual private server so I can edit httpd.conf and other files on the server, and restart Apache. The problem: The web service works perfectly as long as the request is not too large, but around 1MB is the limit. After that, the server responds with: <!DOCTYPE HTML PUBLIC "-//IETF//DTD HTML 2.0//EN"> <html><head> <title>413 Request Entity Too Large</title> </head><body> <h1>Request Entity Too Large</h1> The requested resource<br />/<br /> does not allow request data with POST requests, or the amount of data provided in the request exceeds the capacity limit. </body></html> The web service writes its own log file, and I can see that small messages are processed fine. Larger messages are not logged at all so I guess that something in Apache rejects them before they even reach the web service? Things I've tried without success: (I've restarted Apache after every change. These steps are incremental.) hosting provider's web-based configuration panel: disable mod_security httpd.conf: LimitXMLRequestBody 0 and LimitRequestBody 0 httpd.conf: LimitXMLRequestBody 100000000 and LimitRequestBody 100000000 httpd.conf: SecRequestBodyLimit 100000000 At this stage, Apache's error.log contains a message: ModSecurity: Request body no files data length is larger than the configured limit (1048576) It looks like my step #4 didn't really take, which is consistent with step #1 but does not explain why mod_security appears to be active after all. What more can I try, to get the web service to receive large messages?

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  • HTML5 Web DB Security

    - by darrenc
    Hi all! I'm looking into an offline web app solution using HTML5. The functionality is everything I need BUT the data stored can be directly queried right in the browser and therefore completely unsecure! Is there anyway to encrypt/hide so that the data is secure? Thanks, D.

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  • Spring and hibernate.cfg.xml

    - by Steve Kuo
    How do I get Spring to load Hibernate's properties from hibernate.cfg.xml? We're using Spring and JPA (with Hibernate as the implementation). Spring's applicationContext.xml specifies the JPA dialect and Hibernate properties: <bean id="entityManagerFactory" class="org.springframework.orm.jpa.LocalEntityManagerFactoryBean"> <property name="jpaDialect"> <bean class="org.springframework.orm.jpa.vendor.HibernateJpaDialect" /> </property> <property name="jpaProperties"> <props> <prop key="hibernate.dialect">org.hibernate.dialect.MySQLInnoDBDialect</prop> </props> </property> </bean> In this configuration, Spring is reading all the Hibernate properties via applicationContext.xml . When I create a hibernate.cfg.xml (located at the root of my classpath, the same level as META-INF), Hibernate doesn't read it at all (it's completely ignored). What I'm trying to do is configure Hibernate second level cache by inserting the cache properties in hibernate.cfg.xml: <cache usage="transactional|read-write|nonstrict-read-write|read-only" region="RegionName" include="all|non-lazy" />

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  • Flex 3 file download - Without URLRequest

    - by Srirangan
    Hey guys, My Flex client app has got some data from the back end (RemoteObjects, BlazeDS, Spring). Client has got all the data it needs, it now needs to put some information in a CSV format and make it available for download. Using Flex 3 for this. Any ideas? Thanks, Sri

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  • Display arbitrary size 2d image in opengl

    - by Martin Beckett
    I need to display 2d images in opengl using textures. The image dimensions are not necessarily powers of 2. I thought of creating a larger texture and restricting the display to the part I was using but the image data will be shared with openCV so I don't want to copy data a pixel at a time into a larger texture. EDIT - it turns out that even the simplest Intel on board graphics under Windows supports none-power-of-2 textures.

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  • Modifying Export to Excel in ReportViewer

    - by firedrawndagger
    I have a formatted table in ReportViewer. When I want to export to Excel though - I do not want to export the formatted table - instead I want to output the original/raw/unmassaged data table in an excel file. What's the best way to intercept the Export to Excel function and output data in a different format?

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  • realloc(): invalid next size

    - by Kewley
    I'm having a problem with the realloc function. I'm using C only (so no vector) with LibCurl. The problem I'm having is that I'm getting the following error (realloc(): invalid next size) on the 12th iteration of the write_data function (the function I pass to Curl as a callback, it is called each time libcurl has some data to pass back (data is passed in chunks) ). Trace: Source: http://pastebin.com/WBWhV5fr Thanks in advance,

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  • remove xml tags with XSLT

    - by azathoth
    Hello all I have the following xml file: <xfa:data> <form1> <Page1> <Page2> <contractInfo> ... </contractInfo> <paymentInfo> ... </paymentInfo> </form1> <commercialType> .... </commercialType> <userList> ... </userList> <officesList> ... </officesList> <commercialType> .... </commercialType> <userList> ... </userList> <officesList> ... </officesList> <commercialType> .... </commercialType> <userList> ... </userList> <officesList> ... </officesList> </xfa:data> I want to remove every ocurrence of the commercialType, userList and officesList nodes, so my output would be : <xfa:data> <form1> <Page1> <Page2> <contractInfo> ... </contractInfo> <paymentInfo> ... </paymentInfo> </form1> </xfa:data> How could I do that using XSLT? Thank you

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  • How does WCF RIA Services handle authentication/authorization/security?

    - by Edward Tanguay
    Since no one answered this question: What issues to consider when rolling your own data-backend for Silverlight / AJAX on non-ASP.NET server? Let me ask it another way: How does WCF RIA Services handle authentication/authorization/security at a low level? e.g. how does the application on the server determine that the incoming http request to change data is coming from a valid client and not from non-desirable source, e.g. a denial-of-service bot?

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  • I am wondering how the Plural-Field generic is to be rendered in the REST OpenSocial 1.0 API specifi

    - by DaveGrahamOrg
    In the OpenSocial Data specificaiton 1.0 for a Person object (social profile data) it includes the use of a generic called Plural-Field. The spec can be found at: http://opensocial-resources.googlecode.com/svn/spec/1.0/Social-Data.xml#Person In the 1.0 data specification there is no XSD and no examples showing the use of this generic Plural-Field. After puzzeling the spec for some time I think I might understand the user of this generic. I was hoping that someone could confirm or correct my understanding. For example the accounts field is a generic Plural-Field<Account> while the activities field is Plural-Field <string>. Am I right in assuming that the result XML would look like: <accounts> <Plural-Field> <primary>true</primary> <type>ntlm</type> <value> <Account> <domain>MYDOMAIN</domain> <userid>MYDOMAIN\davegraham</userid> <username>davegraham</username> </Account> </value> </Plural-Field> <Plural-Field> <primary>false</primary> <type>claims</type> <value> <Account> <domain>i:0#.f|claimsDomain</domain> <userid>i:0#.f|claimsDomain|davegraham</userid> <username>davegraham</username> </Account> </value> </Plural-Field> </accounts> <activities> <Plural-Field> <primary>true</primary> <type>ntlm</type> <value>cycling</value> </Plural-Field> <Plural-Field> <primary>false</primary> <type>claims</type> <value>swiming</value> </Plural-Field> </activities> Am I right in my interpretation of the spec?

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  • Why do I get rows of zeros in my 2D fft?

    - by Nicholas Pringle
    I am trying to replicate the results from a paper. "Two-dimensional Fourier Transform (2D-FT) in space and time along sections of constant latitude (east-west) and longitude (north-south) were used to characterize the spectrum of the simulated flux variability south of 40degS." - Lenton et al(2006) The figures published show "the log of the variance of the 2D-FT". I have tried to create an array consisting of the seasonal cycle of similar data as well as the noise. I have defined the noise as the original array minus the signal array. Here is the code that I used to plot the 2D-FT of the signal array averaged in latitude: import numpy as np from numpy import ma from matplotlib import pyplot as plt from Scientific.IO.NetCDF import NetCDFFile ### input directory indir = '/home/nicholas/data/' ### get the flux data which is in ### [time(5day ave for 10 years),latitude,longitude] nc = NetCDFFile(indir + 'CFLX_2000_2009.nc','r') cflux_southern_ocean = nc.variables['Cflx'][:,10:50,:] cflux_southern_ocean = ma.masked_values(cflux_southern_ocean,1e+20) # mask land nc.close() cflux = cflux_southern_ocean*1e08 # change units of data from mmol/m^2/s ### create an array that consists of the seasonal signal fro each pixel year_stack = np.split(cflux, 10, axis=0) year_stack = np.array(year_stack) signal_array = np.tile(np.mean(year_stack, axis=0), (10, 1, 1)) signal_array = ma.masked_where(signal_array > 1e20, signal_array) # need to mask ### average the array over latitude(or longitude) signal_time_lon = ma.mean(signal_array, axis=1) ### do a 2D Fourier Transform of the time/space image ft = np.fft.fft2(signal_time_lon) mgft = np.abs(ft) ps = mgft**2 log_ps = np.log(mgft) log_mgft= np.log(mgft) Every second row of the ft consists completely of zeros. Why is this? Would it be acceptable to add a randomly small number to the signal to avoid this. signal_time_lon = signal_time_lon + np.random.randint(0,9,size=(730, 182))*1e-05 EDIT: Adding images and clarify meaning The output of rfft2 still appears to be a complex array. Using fftshift shifts the edges of the image to the centre; I still have a power spectrum regardless. I expect that the reason that I get rows of zeros is that I have re-created the timeseries for each pixel. The ft[0, 0] pixel contains the mean of the signal. So the ft[1, 0] corresponds to a sinusoid with one cycle over the entire signal in the rows of the starting image. Here are is the starting image using following code: plt.pcolormesh(signal_time_lon); plt.colorbar(); plt.axis('tight') Here is result using following code: ft = np.fft.rfft2(signal_time_lon) mgft = np.abs(ft) ps = mgft**2 log_ps = np.log1p(mgft) plt.pcolormesh(log_ps); plt.colorbar(); plt.axis('tight') It may not be clear in the image but it is only every second row that contains completely zeros. Every tenth pixel (log_ps[10, 0]) is a high value. The other pixels (log_ps[2, 0], log_ps[4, 0] etc) have very low values.

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  • primitives of a programming language

    - by Tim
    Hi, Which do the concepts control flow, data type, statement, expression and operation belong to? Syntax or semantics? What is the relation between control flow, data type, statement, expression, operation, function, ...? How a program is built from these primitives level by level? I would like to understand these primitive concepts and their relations in order to figure out what aspects of a new language should one learn. Thanks and regards!

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  • What is the quickest reliable way to backup a NAS drive to a USB drive?

    - by Tim Murphy
    How would you backup 600+ GB of data on a NAS (Network-Attached Storage) drive to a USB external drive? The NAS drive does not contain mission critical data nonetheless I wish to make weekly copies of it just in case. The NAS drive is almost exclusively used as an archive dump and is rarely updated. However the backup strategy used must have a simple restore procedure so I can confidently say the data now on the NAS drive is exactly how it was at the time of backup. I did try xcopy but seemed like it would take many-many hours and eventually crashed with insufficient memory. http://www.ctunion.com/node/114 suggests I would need to use xxcopy instead due to folder/file name lengths. My concern with xcopy/xxcopy is the length of time it takes. Hoping something else is faster. NAS drive is DLink DNS-313. 1TB drive installed. Connected to router via Ethernet cable. USB drive is Seagate 1TB. Can be connected to Windows Vista (preferred) or Windows 7 PCs. Both PCs are usually connected Wirelessly however ethernet cable can be used during backup to speed up the process.

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  • Jquery autocomplete

    - by Jos
    Hi All, I m using autocomplete from http://bassistance.de/jquery-plugins/jquery-plugin-autocomplete/ jQuery Autocomplete plugin 1.1 i managed to get data from server in below form with sepaerator to id as "-", but i dont want to show this id in list while selecting but sending it as hidden data.Please suggest. Exon: Supplier HJR/VAKJ -1

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  • Mac updated just now, postgres now broken

    - by Dave
    I run postgres 9.1 / ruby 1.9.2 / rails 3.1.0 on a maxbook air for local dev. It's all been running smoothly for months, (though this is the first time I've done development on a mac.) It's a macbook air from last year, and today I got the mac osx software update message as I have a few times before, and my system downloaded approx 450mb of updates and restarted. It now says it's on OSX 10.7.3. Point is, postgres has stopped working, when I start my thin server (mirror heroku cedar) as normal, and then browse to my rails app I get: PG::Error could not connect to server: Permission denied Is the server running locally and accepting connections on Unix domain socket "/var/pgsql_socket/.s.PGSQL.5432"? What happened? After browsing around a few questions I'm still confused, but here's some extra info: Running psql from command line gives same error I can run pgadmin 3 and connect via it and run SQL no problems Running which psql shows the version as /usr/bin/psql I created a PostgreSQL user back when I got the mac (it's always been on lion) I've no idea why, almost certainly I was following a tutorial which I neglected to store in my notes. Point is I am aware there is a _postgres user as well. I know it's rubbish, but apart from a note on passwords, I don't have any extra info on how I configured postgres - though the obvious implication is that I did not use the _postgres user. Anyone have suggestions or information on what might have changed / what I can try to debug and fix? Thanks. Edit: Playing around based on this question and answer: http://stackoverflow.com/questions/7975414/check-status-of-postgresql-server-mac-os-x, see this string of commands: $ sudo su postgreSQL bash-3.2$ /Library/PostgreSQL/9.1/bin/pg_ctl start -D /Library/PostgreSQL/9.1/data pg_ctl: another server might be running; trying to start server anyway server starting bash-3.2$ 2012-04-08 19:03:39 GMT FATAL: lock file "postmaster.pid" already exists 2012-04-08 19:03:39 GMT HINT: Is another postmaster (PID 68) running in data directory "/Library/PostgreSQL/9.1/data"? bash-3.2$ exit

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  • IE is ignoring Z-Index on positioned elements

    - by Mike
    IE yet again is proving to be the bane of my existence. The top of a site I'm working on has a horizontal menu, an item of which triggers a pure-CSS menu that is positioned absolute within the parent menu DIV (positioned relative). This places the menu perfectly in both IE and the W3C compliant browsers. The problem arises when I have more positioned elements further down on the page. These are also positioned relative, because there is data inside them that needs to be positioned absolute... again, this displays properly in all browsers I've tested it on. The problem is, that then the top menu is opened, part is obscured by the positioned elements further down the page - in effect, it's positioned BELOW these elements even though there are z-index properties defined on all. (in both the CSS file and inline). The only way to get IE to display this properly is to place the actual HTML for the menu at the bottom of the page, below (in DOM terms) the positioned elements elsewhere on the page. I would only do this as an absolute last resort. All Elements are the same type (div). Here is the relevant HTML: <div id='menu'> <div id='cat_menu' style='display:none;z-index:10000;'> <table cellspacing='0' cellpadding='0' class='brmenu' width='100%'> [data] </table> </div> <div class='product_new' style='z-index:20;'>[data]</div> <div class='product_listing' style='background-color:#FFFFFF;'>[data]</div> And the relevant CSS: div#menu { height: 26px; padding: 0; position: relative; } div#cat_menu { position: absolute; top: 25px; left: 115px; width: 300px; z-index: 1000; } div.product_new { background-image: url("/images/sp_images.png"); background-position: 0 -108px; background-repeat: no-repeat; padding 0px; height: 40px; font-size: 9pt; margin-top: 5px; position: relative; z-index: 20; }

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  • Accidental Complexity in OpenSSL HMAC functions

    - by Hassan Syed
    SSL Documentation Analaysis This question is pertaining the usage of the HMAC routines in OpenSSL. Since Openssl documentation is a tad on the weak side in certain areas, profiling has revealed that using the: unsigned char *HMAC(const EVP_MD *evp_md, const void *key, int key_len, const unsigned char *d, int n, unsigned char *md, unsigned int *md_len); From here, shows 40% of my library runtime is devoted to creating and taking down **HMAC_CTX's behind the scenes. There are also two additional function to create and destroy a HMAC_CTX explicetly: HMAC_CTX_init() initialises a HMAC_CTX before first use. It must be called. HMAC_CTX_cleanup() erases the key and other data from the HMAC_CTX and releases any associated resources. It must be called when an HMAC_CTX is no longer required. These two function calls are prefixed with: The following functions may be used if the message is not completely stored in memory My data fits entirely in memory, so I choose the HMAC function -- the one whose signature is shown above. The context, as described by the man page, is made use of by using the following two functions: HMAC_Update() can be called repeatedly with chunks of the message to be authenticated (len bytes at data). HMAC_Final() places the message authentication code in md, which must have space for the hash function output. The Scope of the Application My application generates a authentic (HMAC, which is also used a nonce), CBC-BF encrypted protocol buffer string. The code will be interfaced with various web-servers and frameworks Windows / Linux as OS, nginx, Apache and IIS as webservers and Python / .NET and C++ web-server filters. The description above should clarify that the library needs to be thread safe, and potentially have resumeable processing state -- i.e., lightweight threads sharing a OS thread (which might leave thread local memory out of the picture). The Question How do I get rid of the 40% overhead on each invocation in a (1) thread-safe / (2) resume-able state way ? (2) is optional since I have all of the source-data present in one go, and can make sure a digest is created in place without relinquishing control of the thread mid-digest-creation. So, (1) can probably be done using thread local memory -- but how do I resuse the CTX's ? does the HMAC_final() call make the CTX reusable ?. (2) optional: in this case I would have to create a pool of CTX's. (3) how does the HMAC function do this ? does it create a CTX in the scope of the function call and destroy it ? Psuedocode and commentary will be useful.

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