Search Results

Search found 51790 results on 2072 pages for 'long running'.

Page 442/2072 | < Previous Page | 438 439 440 441 442 443 444 445 446 447 448 449  | Next Page >

  • How to change one Button background in a gridview? -- Android

    - by Tstop Studios
    I have a GridView with 16 ImageView buttons. My program makes a random number and when the user clicks a button in the gridview, i want it to take the random number (0-15) and set the background of the tile with the same position as the random number (0-15) to a different image. How can I just change one of the buttons background? Here's my code so far: public class ButtonHider extends Activity { Random random = new Random(); int pos; @Override protected void onCreate(Bundle savedInstanceState) { // TODO Auto-generated method stub super.onCreate(savedInstanceState); setContentView(R.layout.button_hider); pos = random.nextInt(15); GridView gridview = (GridView) findViewById(R.id.gvBH); gridview.setAdapter(new ImageAdapter(this)); gridview.setOnItemClickListener(new OnItemClickListener() { public void onItemClick(AdapterView<?> parent, View v, int position, long id) { pos = random.nextInt(16); if (position == pos) { Toast.makeText(ButtonHider.this, "Found Me!", Toast.LENGTH_SHORT).show(); } else { Toast.makeText(ButtonHider.this, "Try Again!!", Toast.LENGTH_SHORT).show(); } } }); } public class ImageAdapter extends BaseAdapter { private Context mContext; public ImageAdapter(Context c) { mContext = c; } public int getCount() { return 16; } public Object getItem(int position) { return null; } public long getItemId(int position) { return 0; } // create a new ImageView for each item referenced by the Adapter public View getView(int position, View convertView, ViewGroup parent) { ImageView imageView; if (convertView == null) { // if it's not recycled, initialize some // attributes imageView = new ImageView(mContext); imageView.setLayoutParams(new GridView.LayoutParams(100, 100)); imageView.setScaleType(ImageView.ScaleType.CENTER_CROP); imageView.setPadding(15, 15, 15, 15); } else { imageView = (ImageView) convertView; } imageView.setImageResource(R.drawable.bh_b); return imageView; } } }

    Read the article

  • Neo4j Reading data / performing shortest path calculations on stored data

    - by paddydub
    I'm using the Batch_Insert example to insert Data into the database How can i read this data back from the database. I can't find any examples of how i do this. public static void CreateData() { // create the batch inserter BatchInserter inserter = new BatchInserterImpl( "var/graphdb", BatchInserterImpl.loadProperties( "var/neo4j.props" ) ); Map<String,Object> properties = new HashMap<String,Object>(); properties.put( "name", "Mr. Andersson" ); properties.put( "age", 29 ); long node1 = inserter.createNode( properties ); properties.put( "name", "Trinity" ); properties.remove( "age" ); long node2 = inserter.createNode( properties ); inserter.createRelationship( node1, node2, DynamicRelationshipType.withName( "KNOWS" ), null ); inserter.shutdown(); } I would like to store graph data in the database, graph.makeEdge( "s", "c", "cost", (double) 7 ); graph.makeEdge( "c", "e", "cost", (double) 7 ); graph.makeEdge( "s", "a", "cost", (double) 2 ); graph.makeEdge( "a", "b", "cost", (double) 7 ); graph.makeEdge( "b", "e", "cost", (double) 2 ); Dijkstra<Double> dijkstra = getDijkstra( graph, 0.0, "s", "e" ); What is the best method to store this kind data with 10000's of edges. Then run the Dijskra algorighm to find shortest path calculations using the stored graph data.

    Read the article

  • Calling SetWindowsHookEx inside VS2008 debugger always returns NULL

    - by SoMoS
    we're working on a .Net application that does a low level keyboard hook. When we call the SetWindowsHookEx running inside the debugger the call always fail. When running from the compiled executable everything works fine. If we attach to the processs the the SetWindowsHookEx has been called everything works too. I've read somewhere (I can not remember) that VS already does a low level keyboard hook but this shouldn't be a problem as there is the CallNextHook function. Someone knows what's happening? EDIT: The code is pretty straigfoward, the exception is thrown inside debugger but not outside. Public Sub New() m_callback = New NativeMethods.KeyboardHookDelegate(AddressOf KeyboardCallback) End Sub Public Sub Start() m_handle = NativeMethods.SetWindowsHookEx(NativeMethods.HookType.WH_KEYBOARD_LL, m_callback, Marshal.GetHINSTANCE(Reflection.Assembly.GetExecutingAssembly().GetModules()(0)).ToInt32, 0) If m_handle = 0 Then Throw New Exception() End If End Sub

    Read the article

  • 3 or 4 monitors with Nvidia and Ubuntu

    - by Jason
    I saw that you are (were?) running 4 monitors with Ubuntu 8.10 and two Nvidia cards (http://stackoverflow.com/questions/27113/how-to-use-3-monitors). I was curious if you were doing this with Xinerama, a hacked up TwinView config, or multiple X screens, or some other method? Does it work with compiz? I intend to run my Dell 30" in the middle with two 1280x1024 on the sides and continue to use one X screen, and run compiz, on Ubuntu 9.04. Currently, I am using 2 monitors with twinview and compiz, which runs fantastic. I just can't get the third monitor running (unless I enable it in its own X screen, and then enable Xinerama to enable windows to be dragged as if all one X screen, but this breaks compiz, and I don't care much for having separate X screen). I am very interested in knowing how you set up 4 monitors with 2 GPU's. Thanks!

    Read the article

  • How to invalidate cache when benchmarking?

    - by Michael Buen
    I have this code, that when swapping the order of UsingAs and UsingCast, their performance also swaps. using System; using System.Diagnostics; using System.Linq; using System.IO; class Test { const int Size = 30000000; static void Main() { object[] values = new MemoryStream[Size]; UsingAs(values); UsingCast(values); Console.ReadLine(); } static void UsingCast(object[] values) { Stopwatch sw = Stopwatch.StartNew(); int sum = 0; foreach (object o in values) { if (o is MemoryStream) { var m = (MemoryStream)o; sum += (int)m.Length; } } sw.Stop(); Console.WriteLine("Cast: {0} : {1}", sum, (long)sw.ElapsedMilliseconds); } static void UsingAs(object[] values) { Stopwatch sw = Stopwatch.StartNew(); int sum = 0; foreach (object o in values) { if (o is MemoryStream) { var m = o as MemoryStream; sum += (int)m.Length; } } sw.Stop(); Console.WriteLine("As: {0} : {1}", sum, (long)sw.ElapsedMilliseconds); } } Outputs: As: 0 : 322 Cast: 0 : 281 When doing this... UsingCast(values); UsingAs(values); ...Results to this: Cast: 0 : 322 As: 0 : 281 When doing just this... UsingAs(values); ...Results to this: As: 0 : 322 When doing just this: UsingCast(values); ...Results to this: Cast: 0 : 322 Aside from running them independently, how to invalidate the cache so the second code being benchmarked won't receive the cached memory of first code? Benchmarking aside, just loved the fact that modern processors do this caching magic :-)

    Read the article

  • GUID to ByteArray

    - by DutrowLLC
    I just wrote this code to turn a GUID into a byte array. Can anyone shoot any holes in it or suggest something better? public static byte[] getGuidAsByteArray(){ UUID uuid = UUID.randomUUID(); long longOne = uuid.getMostSignificantBits(); long longTwo = uuid.getLeastSignificantBits(); return new byte[] { (byte)(longOne >>> 56), (byte)(longOne >>> 48), (byte)(longOne >>> 40), (byte)(longOne >>> 32), (byte)(longOne >>> 24), (byte)(longOne >>> 16), (byte)(longOne >>> 8), (byte) longOne, (byte)(longTwo >>> 56), (byte)(longTwo >>> 48), (byte)(longTwo >>> 40), (byte)(longTwo >>> 32), (byte)(longTwo >>> 24), (byte)(longTwo >>> 16), (byte)(longTwo >>> 8), (byte) longTwo }; }

    Read the article

  • How to avoid SQLiteException locking errors

    - by TheArchedOne
    I'm developing an android app. It has multiple threads reading from and writing to the android SQLite db. I am receiving the following error: SQLiteException: error code 5: database is locked I understand the SQLite locks the entire db on inserting/updating, but these errors only seems to happen when inserting/updating while I'm running a select query. The select query returns a cursor which is being left open quite a wile (a few seconds some times) while I iterate over it. If the select query is not running, I never get the locks. I'm surprised that the select could be locking the db.... is this possible, or is something else going on? What's the best way to avoid such locks? Thanks TAO

    Read the article

  • Where has my parallel port gone? ioperm(888,1,1) returns -1.

    - by marcusw
    I have an old Dell Dimension 8200 running Gentoo which I use solely to control various things using the parallel port. After shutting it down a few weeks ago, I started it up again today and tried to access the parallel port like I usually do. Unfortunately, my code bombed out when it tried to call ioperm(888,1,1) to grab the parallel port which returned an error code of -1. There have been no changes to the system be it hardware or software, no updates, no tweaking, no dropping the case, no over-amping the data pins, nothing. The port and the software have been working fine for months with no changes, and were working fine when I shut it down last. Running my code with root privileges changes nothing. What is breaking this and how can I fix it?

    Read the article

  • VS 2008 SP1 text editor flickering over remote desktop connection

    - by AltairDusk
    I am connecting from a Windows 7 x64 machine to my dev machine running Windows XP SP3 using the built in remote desktop client. For most apps it works fine with no problems, for Visual Studio whenever I am typing the entire text editor keeps redrawing. I stumbled across this question: http://stackoverflow.com/questions/873849/vs-2008-sp1-over-remote-desktop-constant-repainting and I have tried all of the suggestions in it to no effect, including resetting all VS settings back to default then disabling the suggested settings. Has anyone found a reliable solution to this? I feel like I'm going insane with the screen constantly refreshing when I'm working from home. Some additional information: Remote Desktop is set to run at 1680x1050, 15bit color, Low-speed broadband for the experience setting with all but Visual styles and Persistent bitmap caching unchecked. Visual Studio 2008 Team System is running on the dev machine with Service Pack 1 and Power Commands installed.

    Read the article

  • Readability and IF-block brackets: best practice

    - by MasterPeter
    I am preparing a short tutorial for level 1 uni students learning JavaScript basics. The task is to validate a phone number. The number must not contain non-digits and must be 14 digits long or less. The following code excerpt is what I came up with and I would like to make it as readable as possible. if ( //set of rules for invalid phone number phoneNumber.length == 0 //empty || phoneNumber.length > 14 //too long || /\D/.test(phoneNumber) //contains non-digits ) { setMessageText(invalid); } else { setMessageText(valid); } A simple question I can not quite answer myself and would like to hear your opinions on: How to position the surrounding (outermost) brackets? It's hard to see the difference between a normal and a curly bracket. Do you usually put the last ) on the same line as the last condition? Do you keep the first opening ( on a line by itself? Do you wrap each individual sub-condition in brackets too? Do you align horizontally the first ( with the last ), or do you place the last ) in the same column as the if? Do you keep ) { on a separate line or you place the last ) on the same line with the last sub-condition and then place the opening { on a new line? Or do you just put the ) { on the same line as the last sub-condition? Community wiki. EDIT Please only post opinions regarding the usage and placement of brackets. The code needs not be re-factored. This is for people who have only been introduced to JavaScript a couple of weeks ago. I am not asking for opinions how to write the code so it's shorter or performs better. I would only like to know how do you place brackets around IF-conditions.

    Read the article

  • Web setup project removes files after upgrade from VS2008 to VS2010

    - by Craig Shearer
    I have a web setup project built using VS2008. I've converted my solution to VS2010 and now when I build my new installer and run the install from the MSI it installs fine, then at the last step, removes all the files it's just installed. I have RemovePreviousVersions set to true. If I turn this off the files remain in place (but I get multiple instances in the Programs and Features in the control panel). If I run the install again, the files reappear. From then on, the files always remain, even when installing another version. So, the problem seems to be with running an installer built using VS2008 and then running the same installer built by VS2010. The upgrade GUIDs on each installer are the same. What is the cause and how can I fix this?

    Read the article

  • Installing applications OTA

    - by Ed Marty
    I have a system set up to download jad files on users' Blackberries, but it only works intermittently, and seemingly randomly. If the user clicks on the link within their BlackBerry browser, 95% of the time on the first try an error message will pop up saying there was an HTTP 500 error (which our server never returns). Viewing the details of this message within the blackberry browser, it says nothing but java.lang.nullpointerexception which, again, could not have come from our server (running apache/php). However, if the user clicks on the link a few more times, or navigates away and goes back to that page, it suddenly works. No change on the server, it just shows the application install screen. Unfortunately, this doesn't always work; sometimes the error 500 just keeps showing up. The link is rather long (containing an sha hash as a token as part of the URL), but I would think that a long URL would either always be broken or always work, not work intermittently. The link uses a php script to download the jad and cod files. Linking to the files directly rather than using the script seems to work more often (I haven't determined if that also ever has an error 500 or not), but I can't find any issues with the headers. The content type is set correctly and, like I said, if the headers were an issue, I'd think it would either always work or always break. Any clues?

    Read the article

  • What's the right way to kill child processes in perl before exiting?

    - by rarbox
    I'm running an IRC Bot (Bot::BasicBot) which has two child processes running File::Tail but when exiting, they don't terminate. So I'm killling them using Proc::ProcessTable like this before exiting: my $parent=$$; my $proc_table=Proc::ProcessTable->new(); for my $proc (@{$proc_table->table()}) { kill(15, $proc->pid) if ($proc->ppid == $parent); } It works but I get this warning: 14045: !!! Child process PID:14047 reaped: 14045: !!! Child process PID:14048 reaped: 14045: !!! Your program may not be using sig_child() to reap processes. 14045: !!! In extreme cases, your program can force a system reboot 14045: !!! if this resource leakage is not corrected. What else can I do to kill child processes? The forked process is created using the forkit method in Bot::BasicBot.

    Read the article

  • Ruby New dnssd (bonjour zeroconf) service not appearing while browsing

    - by Poul
    Here is my simple zeroconf (aka bonjour dnssd) browser. If I have other services running when I start the browser I can see it (the 'resolved to' line prints to the screen). However, if I start up another service while this browser is running it will not appear. It just waits at the top of the block so I would expect it to enter the block once a new service is registered. Any ideas? require 'rubygems' require 'dnssd' browser = DNSSD::Service.new browser.browse '_http._tcp.' do |reply| #<-- code seems to wait here for more services DNSSD.resolve reply do |r| puts "resolved to: http://#{r.target}:#{r.port}" end end #example service register_service = DNSSD::register( "My Service","_http._tcp", nil, my_port) do puts "* Registering the service *" end

    Read the article

  • Hibernate triggering constraint violations using orphanRemoval

    - by ptomli
    I'm having trouble with a JPA/Hibernate (3.5.3) setup, where I have an entity, an "Account" class, which has a list of child entities, "Contact" instances. I'm trying to be able to add/remove instances of Contact into a List<Contact> property of Account. Adding a new instance into the set and calling saveOrUpdate(account) persists everything lovely. If I then choose to remove the contact from the list and again call saveOrUpdate, the SQL Hibernate seems to produce involves setting the account_id column to null, which violates a database constraint. What am I doing wrong? The code below is clearly a simplified abstract but I think it covers the problem as I'm seeing the same results in different code, which really is about this simple. SQL: CREATE TABLE account ( INT account_id ); CREATE TABLE contact ( INT contact_id, INT account_id REFERENCES account (account_id) ); Java: @Entity class Account { @Id @Column public Long id; @OneToMany(cascade = CascadeType.ALL, orphanRemoval = true) @JoinColumn(name = "account_id") public List<Contact> contacts; } @Entity class Contact { @Id @Column public Long id; @ManyToOne(optional = false) @JoinColumn(name = "account_id", nullable = false) public Account account; } Account account = new Account(); Contact contact = new Contact(); account.contacts.add(contact); saveOrUpdate(account); // some time later, like another servlet request.... account.contacts.remove(contact); saveOrUpdate(account); Result: UPDATE contact SET account_id = null WHERE contact_id = ? Edit #1: It might be that this is actually a bug http://opensource.atlassian.com/projects/hibernate/browse/HHH-5091

    Read the article

  • Apache with JBOSS using AJP (mod_jk) giving spikes in thread count.

    - by Beginner
    We used Apache with JBOSS for hosting our Application, but we found some issues related to thread handling of mod_jk. Our website comes under low traffic websites and has maximum 200-300 concurrent users during our website's peak activity time. As the traffic grows (not in terms of concurrent users, but in terms of cumulative requests which came to our server), the server stopped serving requests for long, although it didn't crash but could not serve the request till 20 mins. The JBOSS server console showed that 350 thread were busy on both servers although there was enough free memory say, more than 1-1.5 GB (2 servers for JBOSS were used which were 64 bits, 4 GB RAM allocated for JBOSS) In order to check the problem we were using JBOSS and Apache Web Consoles, and we were seeing that the thread were showing in S state for as long as minutes although our pages take around 4-5 seconds to be served. We took the thread dump and found that the threads were mostly in WAITING state which means that they were waiting indefinitely. These threads were not of our Application Classes but of AJP 8009 port. Could somebody help me in this, as somebody else might also got this issue and solved it somehow. In case any more information is required then let me know. Also is mod_proxy better than using mod_jk, or there are some other problems with mod_proxy which can be fatal for me if I switch to mod__proxy? The versions I used are as follows: Apache 2.0.52 JBOSS: 4.2.2 MOD_JK: 1.2.20 JDK: 1.6 Operating System: RHEL 4 Thanks for the help.

    Read the article

  • Which processors can run CIL

    - by JonnyBoats
    Which processors are capable of running Common Intermediate Language(CIL), formerly known as Microsoft Intermediate Language (MSIL)? Clearly any machine that can run Microsoft Windows with .net qualifies as well as machines targeted by the Mono project. It would appear that the .NET Micro Framework has the ability to target other processors not covered by the above, but it is not clear to me that it uses CIL. Does anyone have a list of which processors are capable of running a program in CIL and or interpreting C# directly (as the .NET Micro Framework appears to do)?

    Read the article

  • Too many open files error in Glassfish3 while using https listener

    - by a1ex07
    I have a problem running webservice that requires https connection(Glassfish3). After running for a while, it eventually crashes. Log file show "Failed to load keystore type JKS with path ....config/keystore.jks due to ...config/keystore.jks (Too many open files)". lsof shows that a number of open files are constantly increasing (among others, I noticed that there are many files with type 'sock' and undefined protocol that never get closed). I tried changing the limit of open files, but it resulted in a longer time before crashing... I blamed the webservice, but everything works fine if the application doesn't require confidential protocol. Did I miss anything in http listener configuration ? Or it is rather an application error? Thanks in advance

    Read the article

  • NAS disk - problem with accessing SAMBA

    - by dominolog
    Hello I have a NAS disk running on some version of Linux. The disk is located in local network (5 PC running XP or Vista, all connected to Linksys Router). I have problems accessing NAS resources through SAMBA. The 1st issue is that the NAS is not accessible through hostname (even if it is configured), 2nd point is that it is mostly not accessible through IP manner (\IP_OF_NAS). Rest of services (FTP, HTTP access) works flawlessly. I connected the NAS to my home network (only 1 WinXP and Linsys router) and the NAS is working fine - SAMBA access together with hostname recognition works perfectly. I wonder this is an issue with WINS? Could anybody help? Regards

    Read the article

  • Appearance of a WPF ListView under Windows Vista and Windows XP is not the same

    - by rem
    In a WPF application I have a ListView: <ListView Name="ItemSelList" ItemsSource="{Binding ItemColl}" SelectionChanged="ItemSelList_SelectionChanged"> <ListView.View> <GridView> <GridViewColumn Header="Date" Width="90" DisplayMemberBinding="{Binding Date}"/> <GridViewColumn Header="Time" Width="90" DisplayMemberBinding="{Binding Time}"/> <GridViewColumn Header="Description" Width="250" DisplayMemberBinding="{Binding Description}"/> </GridView> </ListView.View> </ListView> When running application under Windows Vista, everything is OK. When running under Windows XP - the default font size of ListView's rows is too small and rows of the ListView don't change color when user hovers with a mouse over them. How to do so that ListView appearance under Windows XP is the same as under Vista?

    Read the article

  • How does one inject variables into page templates from a custom Drupal module?

    - by Michael T. Smith
    We've created a custom module for organizing and publishing our newsletter content. The issue I'm running into now -- and I'm new to theming and Drupal module development, so it could just be a knowledge issue as opposed to a Drupal issue -- is how to get each newsletter themed. At this point the URL structure of our newsletter will be: /newsletters/{newsletter-name}/{edition-name}/{issue-date} which means that we can create template files in our theme using filenames like page-newsletters-{newsletter-name}-{edition-name}.tpl.php, which is great. The one issue I'm running into is that all of the content comes through in the $content variable of the theme. I'd like to have it come through as different variables (so that I can, inside the theme, place certain content in certain areas.) Is there a proper way for doing this?

    Read the article

  • CPU friendly infinite loop

    - by Adi
    Writing an infinite loop is simple: while(true){ //add whatever break condition here } But this will trash the CPU performance. This execution thread will take as much as possible from CPU's power. What is the best way to lower the impact on CPU? Adding some Thread.Sleep(n) should do the trick, but setting a high timeout value for Sleep() method may indicate an unresponsive application to the operating system. Let's say I need to perform a task each minute or so in a console app. I need to keep Main() running in an "infinite loop" while a timer will fire the event that will do the job. I would like to keep Main() with the lowest impact on CPU. What methods do you suggest. Sleep() can be ok, but as I already mentioned, this might indicate an unresponsive thread to the operating system. LATER EDIT: I want to explain better what I am looking for: I need a console app not Windows service. Console apps can simulate the Windows services on Windows Mobile 6.x systems with Compact Framework. I need a way to keep the app alive as long as the Windows Mobile device is running. We all know that the console app runs as long as its static Main() function runs, so I need a way to prevent Main() function exit. In special situations (like: updating the app), I need to request the app to stop, so I need to infinitely loop and test for some exit condition. For example, this is why Console.ReadLine() is no use for me. There is no exit condition check. Regarding the above, I still want Main() function as resource friendly as possible. Let asside the fingerprint of the function that checks for the exit condition.

    Read the article

  • XDebug, how to disable remote debugging for single .php file?

    - by Kirzilla
    Hello, I'm using Eclipse IDE + remote Xdebug. EclipseIDE is listening 9000 port for some kind of Xdebug information. There are some php scripts running by cron on server. So, every cron execution xdebug is sending information to my workstation and EclipseIDE is trying to find this file in my project. But file couldn't be find because cron running scrits do not relate to the project I'm working with. So, every cron run Eclipse IDE is alerting this message http://img2.pict.com/22/fc/86/3299517/0/screenshot2b142.png I've tried to add to cron executed php scripts some strings... if (function_exists('xdebug_disable')) { xdebug_disable(); } ... but it didn't helped. Any ideas? Thank you

    Read the article

  • Locating memory leak in Apache httpd process, PHP/Doctrine-based application

    - by Sam
    I have a PHP application using these components: Apache 2.2.3-31 on Centos 5.4 PHP 5.2.10 Xdebug 2.0.5 with Remote Debugging enabled APC 3.0.19 Doctrine ORM for PHP 1.2.1 using Query Caching and Results Caching via APC MySQL 5.0.77 using Query Caching I've noticed that when I start up Apache, I eventually end up 10 child processes. As time goes on, each process will grow in memory until each one approaches 10% of available memory, which begins to slow the server to a crawl since together they grow to take up 100% of memory. Here is a snapshot of my top output: PID USER PR NI VIRT RES SHR S %CPU %MEM TIME+ COMMAND 1471 apache 16 0 626m 201m 18m S 0.0 10.2 1:11.02 httpd 1470 apache 16 0 622m 198m 18m S 0.0 10.1 1:14.49 httpd 1469 apache 16 0 619m 197m 18m S 0.0 10.0 1:11.98 httpd 1462 apache 18 0 622m 197m 18m S 0.0 10.0 1:11.27 httpd 1460 apache 15 0 622m 195m 18m S 0.0 10.0 1:12.73 httpd 1459 apache 16 0 618m 191m 18m S 0.0 9.7 1:13.00 httpd 1461 apache 18 0 616m 190m 18m S 0.0 9.7 1:14.09 httpd 1468 apache 18 0 613m 190m 18m S 0.0 9.7 1:12.67 httpd 7919 apache 18 0 116m 75m 15m S 0.0 3.8 0:19.86 httpd 9486 apache 16 0 97.7m 56m 14m S 0.0 2.9 0:13.51 httpd I have no long-running scripts (they all terminate eventually, the longest being maybe 2 minutes long), and I am working under the assumption that once each script terminates, the memory it uses gets deallocated. (Maybe someone can correct me on that). My hunch is that it could be APC, since it stores data between requests, but at the same time, it seems weird that it would store data inside the httpd process. How can I track down which part of my app is causing the memory leak? What tools can I use to see how the memory usage is growing inside the httpd process and what is contributing to it?

    Read the article

  • In Haskell, I want to read a file and then write to it. Do I need strictness annotation?

    - by Steve
    Hi, Still quite new to Haskell.. I want to read the contents of a file, do something with it possibly involving IO (using putStrLn for now) and then write new contents to the same file. I came up with: doit :: String -> IO () doit file = do contents <- withFile tagfile ReadMode $ \h -> hGetContents h putStrLn contents withFile tagfile WriteMode $ \h -> hPutStrLn h "new content" However this doesn't work due to laziness. The file contents are not printed. I found this post which explains it well. The solution proposed there is to include putStrLn within the withFile: doit :: String -> IO () doit file = do withFile tagfile ReadMode $ \h -> do contents <- hGetContents h putStrLn contents withFile tagfile WriteMode $ \h -> hPutStrLn h "new content" This works, but it's not what I want to do. The operation in I will eventually replace putStrLn might be long, I don't want to keep the file open the whole time. In general I just want to be able to get the file content out and then close it before working with that content. The solution I came up with is the following: doit :: String -> IO () doit file = do c <- newIORef "" withFile tagfile ReadMode $ \h -> do a <- hGetContents h writeIORef c $! a d <- readIORef c putStrLn d withFile tagfile WriteMode $ \h -> hPutStrLn h "Test" However, I find this long and a bit obfuscated. I don't think I should need an IORef just to get a value out, but I needed "place" to put the file contents. Also, it still didn't work without the strictness annotation $! for writeIORef. I guess IORefs are not strict by nature? Can anyone recommend a better, shorter way to do this while keeping my desired semantics? Thanks!

    Read the article

< Previous Page | 438 439 440 441 442 443 444 445 446 447 448 449  | Next Page >