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  • How to obtain printed page count if no web-gui or driver-gui is available to show it

    - by Macgreggor at your service
    I am curious if windows print servers can keep a count of the printed pages sent to it? Can an individual PC (WinXP+)? Is there some secret command you can send it (with telnet, dos, etc)? I searched & couldn't find any questions similar to this here so lets keep this open-ended for future people who are curious. Is this more suited towards server fault? Maybe, but this is more about printers & local PC's have print servers now-a-days. Anyhow in my situation I have the following printers (yes old) I am curious on page-counts: HP Laserjet 1300 (using some kind of PC-card to LPT/Parallel adapter, then a network adapter on top of that [Netgear PS101 print server]) Canon Faxphone L80 Epson LX-300+

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  • Manually output HAML start and end tags

    - by trobrock
    I have some code: - count = 0 - @clients.each do |client| %div{:class => "grid_2#{(" alpha" if (count % 3) == 0) || (" omega push_2" if (count % 3) == 2) || " push_1"}"}= link_to h(client.name), client - count += 1 I want to output an opening div tag right after the each statement if the (count % 3) == 0 and out put the end tag at the end of the block if the (count % 3) == 2 but I can't figure out how to get HAML to do this. Any ideas?

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  • Drupal 6: pre-defined variable for amount [count] of custom type items...

    - by artmania
    Hi friends, I'm a drupal newbie... I researched but couldnot find :/ is there any predefined variable that gives my CCK field value count? for example; I have field_logo_sponsor and I need to display all logo items. Now I have 5 item <?php print $node->field_logo_sponsor[0]['view'] ?> <?php print $node->field_logo_sponsor[1]['view'] ?> <?php print $node->field_logo_sponsor[2]['view'] ?> <?php print $node->field_logo_sponsor[3]['view'] ?> <?php print $node->field_logo_sponsor[4]['view'] ?> it is stupid to use it that way :/ if there is any count variable for that, I will just create a loop for that and display them in a for or while loop Appreciate helps! thanks a lot!

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  • PHP 2d array question

    - by Neral
    Hello, So i have a 2 dimensional array that is used over several pages (session) $_SESSION ["Table"][$_SESSION ["count"]] [0] = $filename; $_SESSION ["Table"][$_SESSION ["count"]] [1] = $size; $_SESSION ["Table"][$_SESSION ["count"]] [2] = $floor; $_SESSION ["Table"][$_SESSION ["count"]] [3] = $phone; $_SESSION ["Table"][$_SESSION ["count"]] [4] = $network; $_SESSION ["Table"][$_SESSION ["count"]] [5] = $totalprice; This is used with a form so i can give in multiple input wich gets stored. But my question is how exactly can i calculate the AVERAGE of $total price of all given in results? Meaning for example i have 5 rows so this would mean 5 total prices. How exactly can i acces this value and count everything up / 5? This will happen in a other page so i would like to use sessions for this. /5 simply by count($_Session["table"]) , but really not sure about the other values. Kind Regards.

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  • Using excel, how can I count the number of cells in a column containing the text "true" or "false"?

    - by Jay Elston
    I have a spreadsheet that has a column of cells where each cell contains a single work. I would like to count the occurrences of some words. I can use the COUNTIF function for most words, but if the word is "true" or "false", I get 0. A B 1 apples 2 2 true 0 3 false 0 4 oranges 1 5 apples In the above spreadsheet table, I have these formulas in cells B1, B2, B3 and B4: =COUNTIF(A1:A5,"apples") =COUNTIF(A1:A5,"true") =COUNTIF(A1:A5,"false") =COUNTIF(A1:A5,"oranges) As you can see, I can count apples, but not true or false. I have also tried this: =COUNTIF(A1:A5,TRUE) But that does not work either. Note -- I am using Excel 2007.

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  • How Do I Update a Table From Another Table Only If the Result Count is 1?

    - by Russ Bradberry
    I have a table of 2 tables in a one to many relationship. I want to run an update script that will update the table with the FK of the related table only if there is one result (because if there is multiple then we need to decide which one to use, in another method) Here is what I have so far: UPDATE import_hourly_event_reports i SET i.banner_id = b.banner_id FROM banner b JOIN plan p ON b.plan_id = p.id WHERE b.campain_id = i.campaign_id AND b.size_id = i.size_id AND p.site_id = i.site_id HAVING COUNT(b.banner_id) = 1 As you can see, the HAVING clause doesn't quite work as I'd expect it. I only want to update the row in the import table with the id of the banner from the banner table if the count is equal to 1.

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  • Can I use a string variable to reference a class variable?

    - by rson
    Here's the scenario: I have an external swf file with x number of movieclips in its library that I load into a containing swf. Each MC in the external swf is linked with a class name and referenced on frame 1 as such var unique1:lineSequence1 = new lineSequence1(); the unique1 variable name will match a string variable I create in the containing swf: function initLines():void{ lineLoader = new Loader(); lineLoader.load(new URLRequest("theLines.swf")); //load external swf lineLoader.contentLoaderInfo.addEventListener(Event.COMPLETE, linesLoaded); } function linesLoaded(e:Event):void{ var loadedswf:MovieClip = e.target.content as MovieClip; var initialLines = projects[0].pageid; //projects is an xmllist trace("initialLines: "+initialLines); //returns "initialLines: unique1" lines_holder_mc.addChild(loadedswf.[initialLines]); } I would like to use the initialLines variable as the reference to unique1 instead of hardcoding unique1 into loadedswf.unique1 to reference said variable in the loaded swf.

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  • perl multithreading issue for autoincrement

    - by user3446683
    I'm writing a multi threaded perl script and storing the output in a csv file. I'm trying to insert a field called sl.no. in the csv file for each row entered but as I'm using threads, the sl. no. overlaps in most. Below is an idea of my code snippet. for ( my $count = 1 ; $count <= 10 ; $count++ ) { my $t = threads->new( \&sub1, $count ); push( @threads, $t ); } foreach (@threads) { my $num = $_->join; } sub sub1 { my $num = shift; my $start = '...'; #distributing data based on an internal logic my $end = '...'; #distributing data based on an internal logic my $next; for ( my $x = $start ; $x <= $end ; $x++ ) { my $count = $x + 1; #part of code from which I get @data which has name and age my $j = 0; if ( $x != 0 ) { $count = $next; } foreach (@data) { #j is required here for some extra code flock( OUTPUT, LOCK_EX ); print OUTPUT $count . "," . $name . "," . $age . "\n"; flock( OUTPUT, LOCK_UN ); $j++; $count++; } $next = $count; } return $num; } I need the count to be incremented which is the serial number for the rows that would be inserted in the csv file. Any help would be appreciated.

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  • Issue using Python to solve the Coin problem [closed]

    - by challarao
    I'm attempting to solve a problem commonly known as the Coin problem, but using McNuggets. McNuggets come in boxes containing either 6, 9, or 20 nuggets. I want to write a python script that uses Diophantine equations to determine if a given number of McNuggets n can be exactly purchased in these groupings. For example: 26 McNuggets -- Possible: 1 6-pack, 0 9-packs, 1 20-pack 27 McNuggets -- Possible: 0 6-packs, 3 9-packs, 0 20-packs 28 McNuggets -- Not possible This is my current attempt at writing the solution in Python, but the output is incorrect and I'm not sure what's wrong. n=input("Enter the no.of McNuggets:") a,b,c=0,0,0 count=0 for a in range(n): if 6*a+9*b+20*c==n: count=count+1 break else: for b in range(n): if 6*a+9*b+20*c==n: count=count+1 break else: for c in range(n): if 6*a+9*b+20*c==n: count=count+1 break if count>0: print "It is possible to buy exactly",n,"packs of McNuggetss",a,b,c else: print "It is not possible to buy"

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  • Databinding in combo box

    - by muralekarthick
    Hi I have two forms, and a class, queries return in Stored procedure. Stored Procedure: ALTER PROCEDURE [dbo].[Payment_Join] @reference nvarchar(20) AS BEGIN -- SET NOCOUNT ON added to prevent extra result sets from -- interfering with SELECT statements. SET NOCOUNT ON; -- Insert statements for procedure here SELECT p.iPaymentID,p.nvReference,pt.nvPaymentType,p.iAmount,m.nvMethod,u.nvUsers,p.tUpdateTime FROM Payment p, tblPaymentType pt, tblPaymentMethod m, tblUsers u WHERE p.nvReference = @reference and p.iPaymentTypeID = pt.iPaymentTypeID and p.iMethodID = m.iMethodID and p.iUsersID = u.iUsersID END payment.cs using System; using System.Collections.Generic; using System.Linq; using System.Text; using System.Data; using System.Data.SqlClient; using System.Windows.Forms; namespace Finance { class payment { string connection = global::Finance.Properties.Settings.Default.PaymentConnectionString; #region Fields int _paymentid = 0; string _reference = string.Empty; string _paymenttype; double _amount = 0; string _paymentmethod; string _employeename; DateTime _updatetime = DateTime.Now; #endregion #region Properties public int paymentid { get { return _paymentid; } set { _paymentid = value; } } public string reference { get { return _reference; } set { _reference = value; } } public string paymenttype { get { return _paymenttype; } set { _paymenttype = value; } } public string paymentmethod { get { return _paymentmethod; } set { _paymentmethod = value; } } public double amount { get { return _amount;} set { _amount = value; } } public string employeename { get { return _employeename; } set { _employeename = value; } } public DateTime updatetime { get { return _updatetime; } set { _updatetime = value; } } #endregion #region Constructor public payment() { } public payment(string refer) { reference = refer; } public payment(int paymentID, string Reference, string Paymenttype, double Amount, string Paymentmethod, string Employeename, DateTime Time) { paymentid = paymentID; reference = Reference; paymenttype = Paymenttype; amount = Amount; paymentmethod = Paymentmethod; employeename = Employeename; updatetime = Time; } #endregion #region Methods public void Save() { try { SqlConnection connect = new SqlConnection(connection); SqlCommand command = new SqlCommand("payment_create", connect); command.CommandType = CommandType.StoredProcedure; command.Parameters.Add(new SqlParameter("@reference", reference)); command.Parameters.Add(new SqlParameter("@paymenttype", paymenttype)); command.Parameters.Add(new SqlParameter("@amount", amount)); command.Parameters.Add(new SqlParameter("@paymentmethod", paymentmethod)); command.Parameters.Add(new SqlParameter("@employeename", employeename)); command.Parameters.Add(new SqlParameter("@updatetime", updatetime)); connect.Open(); command.ExecuteScalar(); connect.Close(); } catch { } } public void Load(string reference) { try { SqlConnection connect = new SqlConnection(connection); SqlCommand command = new SqlCommand("Payment_Join", connect); command.CommandType = CommandType.StoredProcedure; command.Parameters.Add(new SqlParameter("@Reference", reference)); //MessageBox.Show("ref = " + reference); connect.Open(); SqlDataReader reader = command.ExecuteReader(); while (reader.Read()) { this.reference = Convert.ToString(reader["nvReference"]); // MessageBox.Show(reference); // MessageBox.Show("here"); // MessageBox.Show("payment type id = " + reader["nvPaymentType"]); // MessageBox.Show("here1"); this.paymenttype = Convert.ToString(reader["nvPaymentType"]); // MessageBox.Show(paymenttype.ToString()); this.amount = Convert.ToDouble(reader["iAmount"]); this.paymentmethod = Convert.ToString(reader["nvMethod"]); this.employeename = Convert.ToString(reader["nvUsers"]); this.updatetime = Convert.ToDateTime(reader["tUpdateTime"]); } reader.Close(); } catch (Exception ex) { MessageBox.Show("Check it again" + ex); } } #endregion } } i have already binded the combo box items through designer, When i run the application i just get the reference populated in form 2 and combo box just populated not the particular value which is fetched. New to c# so help me to get familiar

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  • merging two tables, while applying aggregates on the duplicates (max,min and sum)

    - by cloudraven
    I have a table (let's call it log) with a few millions of records. Among the fields I have Id, Count, FirstHit, LastHit. Id - The record id Count - number of times this Id has been reported FirstHit - earliest timestamp with which this Id was reported LastHit - latest timestamp with which this Id was reported This table only has one record for any given Id Everyday I get into another table (let's call it feed) with around half a million records with these fields among many others: Id Timestamp - Entry date and time. This table can have many records for the same id What I want to do is to update log in the following way. Count - log count value, plus the count() of records for that id found in feed FirstHit - the earliest of the current value in log or the minimum value in feed for that id LastHit - the latest of the current value in log or the maximum value in feed for that id. It should be noticed that many of the ids in feed are already in log. The simple thing that worked is to create a temporary table and insert into it the union of both as in Select Id, Min(Timestamp) As FirstHit, MAX(Timestamp) as LastHit, Count(*) as Count FROM feed GROUP BY Id UNION ALL Select Id, FirstHit,LastHit,Count FROM log; From that temporary table I do a select that aggregates Min(firsthit), max(lasthit) and sum(Count) Select Id, Min(FirstHit),Max(LastHit),Sum(Count) FROM @temp GROUP BY Id; and that gives me the end result. I could then delete everything from log and replace it with everything with temp, or craft an update for the common records and insert the new ones. However, I think both are highly inefficient. Is there a more efficient way of doing this. Perhaps doing the update in place in the log table?

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  • How to generate links to the android Classes' reference in javadoc ?

    - by Kaillash
    Hi, When I generate Javadoc for my android project in eclipse, there are lots of warnings like cannot find symbol symbol : class TextView and warning - Tag @see: reference not found: android.app.Dialog I also tried -link http://developer.android.com/reference/ -link http://java.sun.com/j2se/1.4.2/docs/api/ in Extra javadoc options tab in Configure Javadoc Arguments dialog of eclipse-Export Javadoc. But only -link http://java.sun.com/j2se/1.4.2/docs/api/ is working i.e for String class link http://java.sun.com/j2se/1.4.2/docs/api/java/lang/String.html?is-external=true is generated. but for android.app.Dialog , no link is generated. Please help !!

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  • Excel - Dynamic reference based on the row I paste into?

    - by michaelmichael
    I have a simple, oft-used formula that I paste into spreadsheets I receive. It looks like this: =IF(AND(D8="COMPLETE",E8=""),A8,"") It looks in D8 for the word "COMPLETE" and checks that E8 is blank. If both conditions are fulfilled it grabs the contents of A8. It works fine. The only problem with this is that I don't always paste it into row 8. Every spreadsheet is different. I usually end up spending a few seconds making the formula fit the current spreadsheet I'm working on by dragging the cell references to the appropriate row. Hence, my question: Is there a way to make an absolute row reference based on whatever row I paste into? For example, if I paste the above formula into a cell in row 25, the formula would automatically look like this: =IF(AND(D25="COMPLETE", E25=""), A25, "")

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  • Class Template Instantiation: any way round this circular reference?

    - by TimYorke34
    I have two classes that I'm using to represent some hardware: A Button and an InputPin class which represent a button that will change the value of an IC's input pin when it's pressed down. A simple example of them is: template <int pinNumber> class InputPin { static bool IsHigh() { return ( (*portAddress) & (1<<pinNumber) ); } }; template <typename InputPin> class Button { static bool IsPressed() { return !InputPin::IsHigh(); } }; This works beautifully and by using class templates, the condition below will compile as tightly as if I'd handwritten it in assembly (a single instruction). Button < InputPin<1> > powerButton; if (powerButton.IsPressed()) ........; However, I am extending it to deal with interrupts and have got a problem with circular references. Compared to the original InputPin, a new InputPinIRQ class has an extra static member function that will be called automatically by the hardware when the pin value changes. I'd like it to be able to notify the Button class of this, so that the Button class can then notify the main application that it has been pressed/released. I am currently doing this with function pointers to callbacks. In order for the callback code to be inlined by the compiler, I need to pass the function pointers as template parameters. So now, both of the new classes have an extra template parameter that is a pointer to a callback function. Unfortunately this gives me a circular reference because to instantiate a ButtonIRQ class I now have to do something like this: ButtonIRQ< InputPinIRQ< A1, ButtonIRQ<....>::OnPinChange, OnButtonChange > pB; where the <...... represents the circular reference. Does anyone know how I can avoid this circular reference? I am new to templates, so might be missing something really simple. It's important that the compiler knows exactly what code will be run when the interrupt occurs as it then does some very useful optimisation - it is able to inline the callback function and literally inserts the callback function's code at the exact address that is called on a h/w interrupt.

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  • Python code to do csv file row entries comparison operations and count the number of times row value

    - by Venomancer
    have an excel based CSV file with two columns (or rows, Pythonically) that I am working on. What I need to do is to perform some operations so that I can compare the two data entries in each 'row'. To be more precise, one column has constant numbers all the way down, whereas the other column has varying values. So I need to count the number of times the varying column data entry values crosses the constant value on the other column. For example, fro the csv file i have two columns: Varying Column; Constant Column 24 25 26 25 crossed 27 25 26 25 25.5 25 23 25 crossed 26 25 crossed Thus, the varying column data entries have crossed 25 three times. I need to generate a code that can count the number of the crosses. Please do help out, Thanks.

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  • Why does the assignment operator return a value and not a reference?

    - by Nick Lowman
    I saw the example below explained on this site and thought both answers would be 20 and not the 10 that is returned. He wrote that both the comma and assignment returns a value, not a reference. I don't quite understand what that means. I understand it in relation to passing variables into functions or methods i.e primitive types are passed in by value and objects by reference but I'm not sure how it applies in this case. I also understand about context and the value of 'this' (after help from stackoverflow) but I thought in both cases I would still be invoking it as a method, foo.bar() which would mean foo is the context but it seems both result in a function call bar(). Why is that and what does it all mean? var x = 10; var foo = { x: 20, bar: function () {return this.x;} }; (foo.bar = foo.bar)();//returns 10 (foo.bar, foo.bar)();//returns 10

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  • ggplot: showing % instead of counts in charts of categorical variables

    - by wishihadabettername
    I'm plotting a categorical variable and instead of showing the counts for each category value, I'm looking for a way to get ggplot to display the percentage of values in that category. Of course, it is possible to create another variable with the calculated percentage and plot that one, but I have to do it several dozens of times and I hope to achieve that in one command. I was experimenting with something like qplot (mydataf) + stat_bin(aes(n=nrow(mydataf), y=..count../n)) + scale_y_continuous(formatter="percent") but I must be using it incorrectly, as I got errors. To easily reproduce the setup, here's a simplified example: mydata <- c ("aa", "bb", null, "bb", "cc", "aa", "aa", "aa", "ee", null, "cc"); mydataf <- factor(mydata); qplot (mydataf); #this shows the count, I'm looking to see % displayed. In the real case I'll probably use ggplot instead of qplot, but the right way to use stat_bin still eludes me. Thank you. UPDATE: I've also tried these four approaches: ggplot(mydataf, aes(y = (..count..)/sum(..count..))) + scale_y_continuous(formatter = 'percent'); ggplot(mydataf, aes(y = (..count..)/sum(..count..))) + scale_y_continuous(formatter = 'percent') + geom_bar(); ggplot(mydataf, aes(x = levels(mydataf), y = (..count..)/sum(..count..))) + scale_y_continuous(formatter = 'percent'); ggplot(mydataf, aes(x = levels(mydataf), y = (..count..)/sum(..count..))) + scale_y_continuous(formatter = 'percent') + geom_bar(); but all 4 give: Error: ggplot2 doesn't know how to deal with data of class factor The same error appears for the simple case of ggplot (data=mydataf, aes(levels(mydataf))) + geom_bar() so it's clearly something about how ggplot interacts with a single vector. I'm scratching my head, googling for that error gives a single result.

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  • JQuery - How do I count the number of elements selected by a selector?

    - by Josh
    I am using $().fadeOut() to fade items out in a list ( < li < /li). When the list is empty I wish to hide a parent object. I plan on doing this by checking in my trigger event that fades the list if the count of the objects is 0 then hide the parent element. I can use the fadeOut callback to remove the elements if necessary. The to the point question: How do I select li tags inside a ul and then get the total count of them using jquery?

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  • Count function calls by name or signature. Gcc, C++

    - by MajesticRa
    I have some c++ written package. Linux, gcc. I can modify compilation process (change Makefile, flags, etc.), but can not change C++ source code. One runs the package with different parameters, it does a job and exits. How to count: 1) Number of calls of function with specific name? 2) Number of calls of functions with specific signature? 3) Number of calls of functions where one of the parameters is of specific type i.e. std::string (type is specified by signature)? 4) and extra Number of calls of functions of STL objects, i.e. std::string copy constructor? (I mean count a number of calls during the run. ) I thought to do it with GDB, but I found it very tough to do (1) and have not found how to do (2)-(4) at all. All acceptable answers I will write here for humanity.

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  • How to reference or vlookup a list of values based on a comma separated list of column references within a cell in excel?

    - by glallen
    I want to do a vlookup (or similar) against a column which is a list of values. This works fine for looking up a value from a single row, but I want to be able to look up multiple rows, sum the results, and divide by the number of rows referenced. For example: A B C D E F G [----given values----------------] [Work/Auth] [sum(vlookup(each(G),table,5)) /count(G)] [given vals] 1 Item Authorized OnHand Working Operational% DependencyOR% Dependencies 2 A 1 1 1 1 .55 B 3 B 10 5 5 .50 .55 C,D 4 C 100 75 50 .50 .60 D 5 D 10 10 6 .60 1 I want to be able to show an Operational Rate, and an operational rate of the systems each system depends on (F). In order to get a value for F, I want to sum over each value in column-E that was referenced by a dependency in column-G then divide by the number of dependencies in G. Column-G can have varying lengths, and will be a comma separated list of values from column-A. Is there any way to do this in excel?

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  • Ubuntu 12.04 on Amazon EC2: /dev/xvda1 will be checked for errors at next reboot?

    - by cwd
    I'm running the lastest Ubuntu 12.04 AMI (ami-a29943cb) from Canonical on Amazon EC2 and quite often when I log in I get the message: *** /dev/xvda1 will be checked for errors at next reboot *** I have read a bunch of documentation on this and seem to understand that every so many reboots (around 37 see Mount count / Maximum mount count below) Ubuntu wants to check a disk for errors. I can see that by using dumpe2fs -h /dev/xvda1 (reference) to get information such as: Last mounted on: / Filesystem UUID: 1ad27d06-4ecf-493d-bb19-4710c3caf924 Filesystem magic number: 0xEF53 Filesystem revision #: 1 (dynamic) Filesystem features: has_journal ext_attr resize_inode dir_index filetype needs_recovery extent flex_bg sparse_super large_file huge_file uninit_bg dir_nlink extra_isize Filesystem flags: signed_directory_hash Default mount options: (none) Filesystem state: clean Errors behavior: Continue Filesystem OS type: Linux Inode count: 524288 Block count: 2097152 Reserved block count: 104857 Free blocks: 1778055 Free inodes: 482659 First block: 0 Block size: 4096 Fragment size: 4096 Reserved GDT blocks: 511 Blocks per group: 32768 Fragments per group: 32768 Inodes per group: 8192 Inode blocks per group: 512 Flex block group size: 16 Filesystem created: Tue Apr 24 03:07:48 2012 Last mount time: Thu Nov 8 03:17:58 2012 Last write time: Tue Apr 24 03:08:52 2012 Mount count: 3 Maximum mount count: 37 Last checked: Tue Apr 24 03:07:48 2012 Check interval: 15552000 (6 months) Next check after: Sun Oct 21 03:07:48 2012 Lifetime writes: 2454 MB Reserved blocks uid: 0 (user root) Reserved blocks gid: 0 (group root) First inode: 11 Inode size: 256 Required extra isize: 28 Desired extra isize: 28 Journal inode: 8 Default directory hash: half_md4 Directory Hash Seed: 0a25e04c-6169-4d68-bfa6-a1acd8e39632 Journal backup: inode blocks Journal features: journal_incompat_revoke Journal size: 128M Journal length: 32768 Journal sequence: 0x0000158b Journal start: 1 I've tried these things to get rid of the message and usually the badblocks is what does it for me: Run this command and reboot: sudo touch /forcefsck Run badblocks to check the disk: badblocks /dev/sda1 Edit /etc/fstab and change the last "0" which is the fs_passno column accordingly and then reboot: The root filesystem should be specified with a fs_passno of 1, and other filesystems should have a fs_passno of 2. I don't understand: If this is a virtual drive shouldn't it be less prone to errors? Was the image created with one of the flags set? If not what is triggering it? Why is fs_passno set to 0 on Amazon EC2 Ubuntu images? This is not the first one that is like this.

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  • Creating HTML5 Offline Web Applications with ASP.NET

    - by Stephen Walther
    The goal of this blog entry is to describe how you can create HTML5 Offline Web Applications when building ASP.NET web applications. I describe the method that I used to create an offline Web application when building the JavaScript Reference application. You can read about the HTML5 Offline Web Application standard by visiting the following links: Offline Web Applications Firefox Offline Web Applications Safari Offline Web Applications Currently, the HTML5 Offline Web Applications feature works with all modern browsers with one important exception. You can use Offline Web Applications with Firefox, Chrome, and Safari (including iPhone Safari). Unfortunately, however, Internet Explorer does not support Offline Web Applications (not even IE 9). Why Build an HTML5 Offline Web Application? The official reason to build an Offline Web Application is so that you do not need to be connected to the Internet to use it. For example, you can use the JavaScript Reference Application when flying in an airplane, riding a subway, or hiding in a cave in Borneo. The JavaScript Reference Application works great on my iPhone even when I am completely disconnected from any network. The following screenshot shows the JavaScript Reference Application running on my iPhone when airplane mode is enabled (notice the little orange airplane):   Admittedly, it is becoming increasingly difficult to find locations where you can’t get Internet access. A second, and possibly better, reason to create Offline Web Applications is speed. An Offline Web Application must be downloaded only once. After it gets downloaded, all of the files required by your Web application (HTML, CSS, JavaScript, Image) are stored persistently on your computer. Think of Offline Web Applications as providing you with a super browser cache. Normally, when you cache files in a browser, the files are cached on a file-by-file basis. For each HTML, CSS, image, or JavaScript file, you specify how long the file should remain in the cache by setting cache headers. Unlike the normal browser caching mechanism, the HTML5 Offline Web Application cache is used to specify a caching policy for an entire set of files. You use a manifest file to list the files that you want to cache and these files are cached until the manifest is changed. Another advantage of using the HTML5 offline cache is that the HTML5 standard supports several JavaScript events and methods related to the offline cache. For example, you can be notified in your JavaScript code whenever the offline application has been updated. You can use JavaScript methods, such as the ApplicationCache.update() method, to update the cache programmatically. Creating the Manifest File The HTML5 Offline Cache uses a manifest file to determine the files that get cached. Here’s what the manifest file looks like for the JavaScript Reference application: CACHE MANIFEST # v30 Default.aspx # Standard Script Libraries Scripts/jquery-1.4.4.min.js Scripts/jquery-ui-1.8.7.custom.min.js Scripts/jquery.tmpl.min.js Scripts/json2.js # App Scripts App_Scripts/combine.js App_Scripts/combine.debug.js # Content (CSS & images) Content/default.css Content/logo.png Content/ui-lightness/jquery-ui-1.8.7.custom.css Content/ui-lightness/images/ui-bg_glass_65_ffffff_1x400.png Content/ui-lightness/images/ui-bg_glass_100_f6f6f6_1x400.png Content/ui-lightness/images/ui-bg_highlight-soft_100_eeeeee_1x100.png Content/ui-lightness/images/ui-icons_222222_256x240.png Content/ui-lightness/images/ui-bg_glass_100_fdf5ce_1x400.png Content/ui-lightness/images/ui-bg_diagonals-thick_20_666666_40x40.png Content/ui-lightness/images/ui-bg_gloss-wave_35_f6a828_500x100.png Content/ui-lightness/images/ui-icons_ffffff_256x240.png Content/ui-lightness/images/ui-icons_ef8c08_256x240.png Content/browsers/c8.png Content/browsers/es3.png Content/browsers/es5.png Content/browsers/ff3_6.png Content/browsers/ie8.png Content/browsers/ie9.png Content/browsers/sf5.png NETWORK: Services/EntryService.svc http://superexpert.com/resources/JavaScriptReference/ A Cache Manifest file always starts with the line of text Cache Manifest. In the manifest above, all of the CSS, image, and JavaScript files required by the JavaScript Reference application are listed. For example, the Default.aspx ASP.NET page, jQuery library, JQuery UI library, and several images are listed. Notice that you can add comments to a manifest by starting a line with the hash character (#). I use comments in the manifest above to group JavaScript and image files. Finally, notice that there is a NETWORK: section of the manifest. You list any file that you do not want to cache (any file that requires network access) in this section. In the manifest above, the NETWORK: section includes the URL for a WCF Service named EntryService.svc. This service is called to get the JavaScript entries displayed by the JavaScript Reference. There are two important things that you need to be aware of when using a manifest file. First, all relative URLs listed in a manifest are resolved relative to the manifest file. The URLs listed in the manifest above are all resolved relative to the root of the application because the manifest file is located in the application root. Second, whenever you make a change to the manifest file, browsers will download all of the files contained in the manifest (all of them). For example, if you add a new file to the manifest then any browser that supports the Offline Cache standard will detect the change in the manifest and download all of the files listed in the manifest automatically. If you make changes to files in the manifest (for example, modify a JavaScript file) then you need to make a change in the manifest file in order for the new version of the file to be downloaded. The standard way of updating a manifest file is to include a comment with a version number. The manifest above includes a # v30 comment. If you make a change to a file then you need to modify the comment to be # v31 in order for the new file to be downloaded. When Are Updated Files Downloaded? When you make changes to a manifest, the changes are not reflected the very next time you open the offline application in your web browser. Your web browser will download the updated files in the background. This can be very confusing when you are working with JavaScript files. If you make a change to a JavaScript file, and you have cached the application offline, then the changes to the JavaScript file won’t appear when you reload the application. The HTML5 standard includes new JavaScript events and methods that you can use to track changes and make changes to the Application Cache. You can use the ApplicationCache.update() method to initiate an update to the application cache and you can use the ApplicationCache.swapCache() method to switch to the latest version of a cached application. My heartfelt recommendation is that you do not enable your application for offline storage until after you finish writing your application code. Otherwise, debugging the application can become a very confusing experience. Offline Web Applications versus Local Storage Be careful to not confuse the HTML5 Offline Web Application feature and HTML5 Local Storage (aka DOM storage) feature. The JavaScript Reference Application uses both features. HTML5 Local Storage enables you to store key/value pairs persistently. Think of Local Storage as a super cookie. I describe how the JavaScript Reference Application uses Local Storage to store the database of JavaScript entries in a separate blog entry. Offline Web Applications enable you to store static files persistently. Think of Offline Web Applications as a super cache. Creating a Manifest File in an ASP.NET Application A manifest file must be served with the MIME type text/cache-manifest. In order to serve the JavaScript Reference manifest with the proper MIME type, I added two files to the JavaScript Reference Application project: Manifest.txt – This text file contains the actual manifest file. Manifest.ashx – This generic handler sends the Manifest.txt file with the MIME type text/cache-manifest. Here’s the code for the generic handler: using System.Web; namespace JavaScriptReference { public class Manifest : IHttpHandler { public void ProcessRequest(HttpContext context) { context.Response.ContentType = "text/cache-manifest"; context.Response.WriteFile(context.Server.MapPath("Manifest.txt")); } public bool IsReusable { get { return false; } } } } The Default.aspx file contains a reference to the manifest. The opening HTML tag in the Default.aspx file looks like this: <html manifest="Manifest.ashx"> Notice that the HTML tag contains a manifest attribute that points to the Manifest.ashx generic handler. Internet Explorer simply ignores this attribute. Every other modern browser will download the manifest when the Default.aspx page is requested. Seeing the Offline Web Application in Action The experience of using an HTML5 Web Application is different with different browsers. When you first open the JavaScript Reference application with Firefox, you get the following warning: Notice that you are provided with the choice of whether you want to use the application offline or not. Browsers other than Firefox, such as Chrome and Safari, do not provide you with this choice. Chrome and Safari will create an offline cache automatically. If you click the Allow button then Firefox will download all of the files listed in the manifest. You can view the files contained in the Firefox offline application cache by typing about:cache in the Firefox address bar: You can view the actual items being cached by clicking the List Cache Entries link: The Offline Web Application experience is different in the case of Google Chrome. You can view the entries in the offline cache by opening the Developer Tools (hit Shift+CTRL+I), selecting the Storage tab, and selecting Application Cache: Notice that you view the status of the Application Cache. In the screen shot above, the status is UNCACHED which means that the files listed in the manifest have not been downloaded and cached yet. The different possible values for the status are included in the HTML5 Offline Web Application standard: UNCACHED – The Application Cache has not been initialized. IDLE – The Application Cache is not currently being updated. CHECKING – The Application Cache is being fetched and checked for updates. DOWNLOADING – The files in the Application Cache are being updated. UPDATEREADY – There is a new version of the Application. OBSOLETE – The contents of the Application Cache are obsolete. Summary In this blog entry, I provided a description of how you can use the HTML5 Offline Web Application feature in the context of an ASP.NET application. I described how this feature is used with the JavaScript Reference Application to store the entire application on a user’s computer. By taking advantage of this new feature of the HTML5 standard, you can improve the performance of your ASP.NET web applications by requiring users of your web application to download your application once and only once. Furthermore, you can enable users to take advantage of your applications anywhere -- regardless of whether or not they are connected to the Internet.

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  • How to translate formulas into form of natural language?

    - by Ricky
    I am recently working on a project aiming at evaluating whether an android app crashes or not. The evaluation process is 1.Collect the logs(which record the execution process of an app). 2.Generate formulas to predict the result (formulas is generated by GP) 3.Evaluate the logs by formulas Now I can produce formulas, but for convenience for users, I want to translate formulas into form of natural language and tell users why crash happened.(I think it looks like "inverse natural language processing".) To explain the idea more clearly, imagine you got a formula like this: 155 - count(onKeyDown) >= 148 It's obvious that if count(onKeyDown) 7, the result of "155 - count(onKeyDown) = 148" is false, so the log contains more than 7 onKeyDown event would be predicted "Failed". I want to show users that if onKeyDown event appears more than 7 times(155-148=7), this app will crash. However, the real formula is much more complicated, such as: (< !( ( SUM( {Att[17]}, Event[5]) <= MAX( {Att[7]}, Att[0] >= Att[11]) OR SUM( {Att[17]}, Event[5]) > MIN( {Att[12]}, 734 > Att[19]) ) OR count(Event[5]) != 1 ) > (< count(Att[4] = Att[3]) >= count(702 != Att[8]) + 348 / SUM( {Att[13]}, 641 < Att[12]) mod 587 - SUM( {Att[13]}, Att[10] < Att[15]) mod MAX( {Att[13]}, Event[2]) + 384 > count(Event[10]) != 1)) I tried to implement this function by C++, but it's quite difficult, here's the snippet of code I am working right now. Does anyone knows how to implement this function quickly?(maybe by some tools or research findings?)Any idea is welcomed: ) Thanks in advance.

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  • Why can't I compile this version of Postfix?

    - by Coofucoo
    I just installed postfix 2.7.11 in Ubuntu server from source code. I do not use the ubuntu own one because I need the old version. I found a very interesting problem. Before, in both CentOS 5 and 6, I can build the source code without any problem. But, in Ubuntu server 12.04 is totally different. I got the following problems: dict_nis.c:173: error: undefined reference to 'yp_match' dict_nis.c:187: error: undefined reference to 'yp_match' dns_lookup.c:347: error: undefined reference to '__dn_expand' dns_lookup.c:218: error: undefined reference to '__res_search' dns_lookup.c:287: error: undefined reference to '__dn_expand' dns_lookup.c:498: error: undefined reference to '__dn_expand' dns_lookup.c:383: error: undefined reference to '__dn_expand' Yes, this reason is obviously. I just search related library and add it to the makefile. It works. The question is why? What is the difference between Ubuntu Server and CentOS? One possibility is gcc and ld version. Ubuntu server use different version of gcc and ld with CentOS. But I am not sure.

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