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• FastCGI and Apache 500 error intermittently

  - by benkorn1

  I have a FastCGI (mod_fastcgi)problem. It happens every once in a while, and does not casue a complete server meltdown, just 500 errors. Here are a couple things. First I am using APC so PHP is in control of it's own processes, not FastCGI. Also, I have the webroot set as: /var/www/html And the fcgi-bin inside: /var/www/html/fcgi-bin First off here is the apache error_log: [Fri Jan 07 10:22:39 2011] [error] [client 50.16.222.82] (4)Interrupted system call: FastCGI: comm with server "/var/www/html/fcgi-bin/php.fcgi" aborted: select() failed, referer: http://www.domain.com/ I also ran strace on the 'fcgi-pm' process. Here is a snip from the trace around the time it bombs out: 21725 gettimeofday({1294420603, 14360}, NULL) = 0 21725 read(14, "C /var/www/html/fcgi-bin/php.fcgi - - 6503 38*", 16384) = 46 21725 alarm(131) = 0 21725 select(15, [14], NULL, NULL, NULL) = 1 (in [14]) 21725 alarm(0) = 131 21725 gettimeofday({1294420603, 96595}, NULL) = 0 21725 read(14, "C /var/www/html/fcgi-bin/php.fcgi - - 6154 23*C /var/www/html/fcgi-bin/php.fcgi - - 6483 28*", 16384) = 92 21725 alarm(131) = 0 21725 select(15, [14], NULL, NULL, NULL) = 1 (in [14]) 21725 alarm(0) = 131 21725 gettimeofday({1294420603, 270744}, NULL) = 0 21725 read(14, "C /var/www/html/fcgi-bin/php.fcgi - - 5741 38*", 16384) = 46 21725 alarm(131) = 0 21725 select(15, [14], NULL, NULL, NULL) = 1 (in [14]) 21725 alarm(0) = 131 21725 gettimeofday({1294420603, 311502}, NULL) = 0 21725 read(14, "C /var/www/html/fcgi-bin/php.fcgi - - 6064 32*", 16384) = 46 21725 alarm(131) = 0 21725 select(15, [14], NULL, NULL, NULL) = 1 (in [14]) 21725 alarm(0) = 131 21725 gettimeofday({1294420603, 365598}, NULL) = 0 21725 read(14, "C /var/www/html/fcgi-bin/php.fcgi - - 6179 33*C /var/www/html/fcgi-bin/php.fcgi - - 5906 59*", 16384) = 92 21725 alarm(131) = 0 21725 select(15, [14], NULL, NULL, NULL) = 1 (in [14]) 21725 alarm(0) = 131 21725 gettimeofday({1294420603, 454405}, NULL) = 0 I noticed that the 'select()' seems to stay the same regardless, however the read() changes its return from 46 to some other number while it is bombing out. Has anyone seen anything like this. Could this be some sort of file locking? Thanks, Ben

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• List.Sort in C#: comparer being called with null object

  - by cbp

  I am getting strange behaviour using the built-in C# List.Sort function with a custom comparer. For some reason it sometimes calls the comparer class's Compare method with a null object as one of the parameters. But if I check the list with the debugger there are no null objects in the collection. My comparer class looks like this: public class DelegateToComparer<T> : IComparer<T> { private readonly Func<T,T,int> _comparer; public int Compare(T x, T y) { return _comparer(x, y); } public DelegateToComparer(Func<T, T, int> comparer) { _comparer = comparer; } } This allows a delegate to be passed to the List.Sort method, like this: mylist.Sort(new DelegateToComparer<MyClass>( (x, y) => { return x.SomeProp.CompareTo(y.SomeProp); }); So the above delegate will throw a null reference exception for the x parameter, even though no elements of mylist are null. UPDATE: Yes I am absolutely sure that it is parameter x throwing the null reference exception! UPDATE: Instead of using the framework's List.Sort method, I tried a custom sort method (i.e. new BubbleSort().Sort(mylist)) and the problem went away. As I suspected, the List.Sort method passes null to the comparer for some reason.

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• script not run after reboot from /etc/rc3.d

  - by yael

  I create symbolic link to the file - /etc/rc3.d/platform.bash from /var/tmp/platform.bash ln -s /var/tmp/platform.bash /etc/rc3.d/platform.bash script exist under /var/tmp : -rwxr-xr-x 1 root root 58442 Aug 30 08:49 platform.bash view from /etc/rc3.d : lrwxrwxrwx 1 root root 31 Aug 30 06:33 S99platform.bash -> /var/tmp/platform.bash my target is to run platform.bash after reboot ( on solaris 10 OS ) from some reason the script platform.bash not run after reboot ? please advice what I need to check in order to verify the problem ? my script ( platform.bash ) #!/bin/bash echo test > /var/tmp/log.txt

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• SQL Server 2008: Comparing similar records - Need to still display an ID for a record when the JOIN has no matches

  - by aleppke

  I'm writing a SQL Server 2008 report that will compare genetic test results for animals. A genetic test consists of an animalId, a gene and a result. Not all animals will have the same genes tested but I need to be able to display the results side-by-side for a given set of animals and only include the genes that are present for at least one of the selected animals. My TestResult table has the following data in it: animalId gene result 1 a CC 1 b CT 1 d TT 2 a CT 2 b CT 2 c TT 3 a CT 3 b TT 3 c CC 3 d CC 3 e TT I need to generate a result set that looks like the following. Note that Animal 3 is not being displayed (user doesn't want to see its results) and neither are results for Gene "e" since neither Animal 1 nor Animal 2 have a result for that gene: SireID SireResult CalfID CalfResult Gene 1 CC 2 CT a 1 CT 2 CT b 1 NULL 2 TT c 1 TT 2 NULL d But I can only manage to get this: SireID SireResult CalfID CalfResult Gene 1 CC 2 CT a 1 CT 2 CT b NULL NULL 2 TT c 1 TT NULL NULL d This is the query I'm using. SELECT sire.animalId AS 'SireID' ,sire.result AS 'SireResult' ,calf.animalId AS 'CalfID' ,calf.result AS 'CalfResult' ,sire.gene AS 'Gene' FROM (SELECT s.animalId ,s.result ,m1.gene FROM (SELECT [animalId ] ,result ,gene FROM TestResult WHERE animalId IN (1)) s FULL JOIN (SELECT DISTINCT gene FROM TestResult WHERE animalId IN (1, 2)) m1 ON s.marker = m1.marker) sire FULL JOIN (SELECT c.animalId ,c.result ,m2.gene FROM (SELECT animalId ,result ,gene FROM TestResult WHERE animalId IN (2)) c FULL JOIN (SELECT DISTINCT gene FROM TestResult WHERE animalId IN (1, 2)) m2 ON c.gene = m2.gene) calf ON sire.gene = calf.gene How do I get the SireIDs and CalfIDs to display their values when they don't have a record associated with a particular Gene? I was thinking of using COALESCE but I can't figure out how to specify the correct animalId to pass in. Any help would be appreciated.

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• findViewById returns null in new Intent

  - by drozzy

  I am having a problem where in the started Intent, the findViewById returns null. Is there anything special I should know about starting a new intent? It goes something like this for me: //in the MainList class Intent stuffList = new Intent(this, StuffList.class); then in the new Stuff's constructor: public class StuffList extends ListActivity { @Override public void onCreate(Bundle savedInstanceState) { super.onCreate(savedInstanceState); this.setContentView(R.layout.stuff_list); ... this.setListAdapter(new StuffAdapter(this, my_cursor)); and in the StuffAdapter I do my usual view and data retrieval. Note the line where findViewById returns null: class ViewWrapper{ View base; TextView label = null; ViewWrapper(View base){ this.base = base; } TextView getLabel(){ if(label == null){ label = (TextView)base.findViewById(R.id.my_label); // returns NULL } return label;} } class StuffAdapter extends CursorAdapter{ StuffAdapter(Context context, Cursor cursor){ super(context, cursor); } @Override public View newView(Context context, Cursor cursor, ViewGroup parent) { LayoutInflater inflater = getLayoutInflater(); View row = inflater.inflate(R.layout.stuff_list, parent, false); ViewWrapper wrapper = new ViewWrapper(row); row.setTag(wrapper); return(row); } @Override public void bindView(View row, Context context, Cursor cursor) { ViewWrapper wrapper = (ViewWrapper)row.getTag(); TextView label = wrapper.getLabel(); // also NULL //this throws exception of course label.setText(cursor.getString("title")); } } The curious thing is that in the class that calls intent (MainList class), I do Exactly the same thing (i list a bunch of objects), and it Works! however when I try to do it in an Intent - it can't seem to find the view by id.

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• Setting nested object to null when selected option has empty value

  - by Javi

  Hello, I have a Class which models a User and another which models his country. Something like this: public class User{ private Country country; //other attributes and getter/setters } public class Country{ private Integer id; private String name; //other attributes and getter/setters } I have a Spring form where I have a combobox so the user can select his country or can select the undefined option to indicate he doen't want to provide this information. So I have something like this: <form:select path="country"> <form:option value="">-Select one-</form:option> <form:options items="${countries}" itemLabel="name" itemValue="id"/> </form:select> In my controller I get the autopopulated object with the user information and I want to have country set to null when the "-Select one-" option has been selected. So I have set a initBinder with a custom editor like this: @InitBinder protected void initBinder(WebDataBinder binder) throws ServletException { binder.registerCustomEditor(Country.class, "country", new CustomCountryEditor()); } and my editor do something like this: public class CustomCountryEditor(){ @Override public String getAsText() { //I return the Id of the country } @Override public void setAsText(String str) { //I search in the database for a country with id = new Integer(str) //and set country to that value //or I set country to null in case str == null } } When I submit the form it works because when I have country set to null when I have selected "-Select one-" option or the instance of the country selected. The problem is that when I load the form I have a method like the following one to load the user information. @ModelAttribute("user") public User getUser(){ //loads user from database } The object I get from getUser() has country set to a specific country (not a null value), but in the combobox is not selected any option. I've debugged the application and the CustomCountryEditor works good when setting and getting the text, thoughgetAsText method is called for every item in the list "countries" not only for the "country" field. Any idea? Is there a better way to set null the country object when I select no country option in the combobox? Thanks

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• CSS - Could use some pointers on correct positioning

  - by Kenny Bones

  Hi, I'm in need for some pointers on positioning. I've got this square which should be centered on the page. And with a logo and a logo font image kinda wrapped around the square. Now, I want this as dynamic as possible, because I use both the square and images elsewhere as well. So I can't really use stiff static positioning. This is the site: www.matkalenderen.no How should I do this? I want to logo to appear on the left side of the square. And the font to appear above the square. And the square itself should be centered. You probably get the picture :) Right now I've got a wrapper around everything, which is also centered.

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• Null Pointer Exception in Primavera P6 8.1

  - by gwrichard

  I am getting a null pointer exception in a Primavera P6 8.1 installation. The exception only occurs in one section of the web-client: Application settings.P6 web and the P6 API are deployed on the same WebLogic (10.3.5) node running on a Windows Server 2008 R2 installation. I have done this installation using this same software stack a dozen times and don't have this issue on any of the other installs. Exact error below: Match: beginTraversal Match: digest selected JREDesc: JREDesc[version 1.6.0_20+, heap=-1--1, args=null, href=http://java.sun.com/products/autodl/j2se, sel=false, null, null], JREInfo: JREInfo for index 0: platform is: 1.7 product is: 1.7.0_17 location is: http://java.sun.com/products/autodl/j2se path is: C:\Program Files (x86)\Java\jre7\bin\javaw.exe args is: null native platform is: Windows, x86 [ x86, 32bit ] JavaFX runtime is: JavaFX 2.2.7 found at C:\Program Files (x86)\Java\jre7\ enabled is: true registered is: true system is: true Match: ignoring maxHeap: -1 Match: ignoring InitHeap: -1 Match: digesting vmargs: null Match: digested vmargs: [JVMParameters: isSecure: true, args: ] Match: JVM args after accumulation: [JVMParameters: isSecure: true, args: ] Match: digest LaunchDesc: http://localhost:7001/p6/action/jnlp/appletsjnlp.jnlp?mainClass=com.primavera.pvapplets.adminpreferences.AdminPreferencesApplet&classPath=adminpreferences.jar,prm-applets-common.jar,forms-1.0.7.jar,prm-guisupport.jar,prm-to.jar,jide.jar,tablesupport.jar,formsupport.jar,applets-bo.jar,commons-lang.jar,prm-common.jar,resource_strings.jar,prm-img.jar,commons-logging.jar&name=AdminPreferences&version=8.1.2.0.0602 Match: digest properties: [] Match: JVM args: [JVMParameters: isSecure: true, args: ] Match: endTraversal .. Match: JVM args final: Match: Running JREInfo Version match: 1.7.0.17 == 1.7.0.17 Match: Running JVM args match: have:<> satisfy want:<> Java Plug-in 10.17.2.02 Using JRE version 1.7.0_17-b02 Java HotSpot(TM) Client VM User home directory = C:\Users\gwrichard ---------------------------------------------------- c: clear console window f: finalize objects on finalization queue g: garbage collect h: display this help message l: dump classloader list m: print memory usage o: trigger logging q: hide console r: reload policy configuration s: dump system and deployment properties t: dump thread list v: dump thread stack x: clear classloader cache 0-5: set trace level to <n> ----------------------------------------------------

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• Casting array of pointers to objects

  - by ritmbo

  If B is subclass of A. And I have in main(): B** b = new B*[10]; ... some algorithm that do b[i] = new B(..); ... So I have an array of pointers to objets B. Then I have a function: void f(A** foo); If in main, I do: f(b); I get a warning, but obviously if I do: f((A**)b);, i dont. The (A**) its a bit nasty. I was wondering if there's a more elegant way in C++ that at least do type checking as dynamic_cast.

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• Only compiles as an array of pointers, not array of arrays

  - by Dustin

  Suppose I define two arrays, each of which have 2 elements (for theoretical purposes): char const *arr1[] = { "i", "j" }; char const *arr2[] = { "m", "n" }; Is there a way to define a multidimensional array that contains these two arrays as elements? I was thinking of something like the following, but my compiler displays warnings about incompatible types: char const *combine[][2] = { arr1, arr2 }; The only way it would compile was to make the compiler treat the arrays as pointers: char const *const *combine[] = { arr1, arr2 }; Is that really the only way to do it or can I preserve the type somehow (in C++, the runtime type information would know it is an array) and treat combine as a multidimensional array? I realise it works because an array name is a const pointer, but I'm just wondering if there is a way to do what I'm asking in standard C/C++ rather than relying on compiler extensions. Perhaps I've gotten a bit too used to Python's lists where I could just throw anything in them...

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• va_arg with pointers

  - by Yktula

  I want to initialize a linked list with pointer arguments like so: /* * Initialize a linked list using variadic arguments * Returns the number of structures initialized */ int init_structures(struct structure *first, ...) { struct structure *s; unsigned int count = 0; va_list va; va_start(va, first); for (s = first; s != NULL; s = va_arg(va, (struct structure *))) { if ((s = malloc(sizeof(struct structure))) == NULL) { perror("malloc"); exit(EXIT_FAILURE); } count++; } va_end(va); return count; } The problem is that clang errors type name requires a specifier or qualifier at va_arg(va, (struct structure *)), and says that the type specifier defaults to int. It also notes instantiated form at (struct structure *) and struct structure *. This, what seems to be getting assigned to s is int (struct structure *). It compiles fine when parentheses are removed from (struct structure *), but the structures that are supposed to be initialized are inaccessible. Why is int assumed when parentheses are around the type argument passed to va_arg? How can I fix this?

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• Quick question about pointers

  - by xbonez

  So, I have this code fragment: int * iPtr ; int * jPtr ; int i = 5, k = 7; iPtr = &i; jPtr = iPtr ; I have just started learning about pointers, and need to get some doubts cleared. is jPtr now essentially also pointing at i? I know I can change the value of i by using *iPtr, but how can I change the value of the object being pointed to by jPtr? How will changing the object being pointed to by jPtr affect the value of the object pointed to by iPtr, and i ?

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• How to synchronize users, passwords, hosts, etc without NIS

  - by joshxdr

  I am administering a very small solaris 2.6 network with 4 boxes total. Is it possible to use scp or similar to replace NIS for synchronizing users, groups, hosts, etc? This network is only a small part of my job and I don't want to spend too much time on it, and I am worried the setup and maintenence of NIS will not pay off. I need it to behave like a proper multi-user system, when a user logs into any machine, the users, passwords, hosts, etc. are always the same. Is there an easy way to do this with scp? Right now I copy /etc/passwd from one box to another with scp, but sometimes I make mistakes or forget a step, and scp inside of shell scripts don't seem to works so well since they require password authentication. Any recommendations would be welcome.

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• Swapping values using pointers

  - by xbonez

  I have this code fragment int i = 5; int k = 7; int * iPtr; int * jPtr; int * kPtr; iPtr = &i; kPtr = &k; I am required to swap i and k using the pointers. This is how I'm doing it: *jPtr = *kPtr ; *kPtr = *iPtr ; *iPtr = *jPtr ; Is this the best way to do it, or is there a better way?

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• Selecting date NOT NULL records between a specific range with Propel

  - by Jon Winstanley

  Using Propel I would like to find records which have a date field which is not null and also between a specific range. However, Propel seems to overwrite the criteria with the NOTNULL criteria. Is it possible to do this? //create the date ranges $start_date = mktime(0, 0, 0, date("m") , date("d")+$start, date("Y")); $end_date = mktime(0, 0, 0, date("m") , date("d")+$end, date("Y")); //add the start of the range $c1 = $c->getNewCriterion(TaskPeer::DUE_DATE, null); $c1->addAnd($c->getNewCriterion(TaskPeer::DUE_DATE, $end_date, Criteria::LESS_EQUAL)); $c->add($c1); //add the end of the range $c2 = $c->getNewCriterion(TaskPeer::DUE_DATE, null); $c2->addAnd($c->getNewCriterion(TaskPeer::DUE_DATE, $start_date, Criteria::GREATER_EQUAL)); $c->add($c2); //remove the null entries $c3 = $c->getNewCriterion(TaskPeer::DUE_DATE, null); $c3->addAnd($c->getNewCriterion(TaskPeer::DUE_DATE, null, Criteria::ISNULL)); $c->add($c3);

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• Template meta-programming with member function pointers?

  - by wheaties

  Is it possible to use member function pointers with template meta-programming? Such as: class Connection{ public: string getName() const; string getAlias() const; //more stuff }; typedef string (Connection::*Con_Func)() const; template<Con_Func _Name> class Foo{ Connection m_Connect; public: void Foo(){ cout << m_Connect.(*_Name); } }; typedef Foo<&Connection::getName> NamedFoo; typedef Foo<&Connection::getAlias> AliasFoo; Granted, this is rather contrived but is it possible? (yes, there are probably much better ways but humor me.)

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• Groovy htmlunit getFirstByXPath returning null

  - by StartingGroovy

  I have had a few issues with HtmlUnit returning nulls lately and am looking for guidance. each of my results for grabbing the first row of a website have returned null. I am wondering if someone can A) explain why they might be returning null B) explain better ways (if there are some) to go about getting the information Here is my current code (URL is in the source): client = new WebClient(BrowserVersion.FIREFOX_3) client.javaScriptEnabled = false def url = "http://www.hidemyass.com/proxy-list/" page = client.getPage(url) IpAddress = page.getFirstByXPath("//html/body/div/div/form/table/tbody/tr/td[2]").getValue() println "IP Address is: $data" //returns null //Port_Number is an Image Country = page.getFirstByXPath("//html/body/div/div/form/table/tbody/tr/td[4][@class='country']/@rel").getValue() println "Country abbreviation is: $Country" //differentiate speed and connection by name of gif? Type = page.getFirstByXPath("//html/body/div/div/form/table/tbody/tr/td[7]").getValue() println "Proxy type is: $Type" Anonymity = page.getFirstByXPath("//html/body/div/div/form/table/tbody/tr/td[8]").getValue() println "Anonymity Level is: $Anonymity" client.closeAllWindows() Right now all of my XPaths return null and .getValue() obviously doesn't work on null. I also have questions as to what I should do about the PORT since it is an image? Is there a better alternative than downloading it and attempting to solve it by OCR? Side Note There is no significance in this site, I was just looking for a site that I could practice scraping on (the last one I ran into issues of fragment identities and couldn't get an answer to: HtmlUnit getByXpath returns null and HtmlUnit and Fragment Identities )

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• Can I use memcpy in C++ to copy classes that have no pointers or virtual functions

  - by Shane MacLaughlin

  Say I have a class, something like the following; class MyClass { public: MyClass(); int a,b,c; double x,y,z; }; #define PageSize 1000000 MyClass Array1[PageSize],Array2[PageSize]; If my class has not pointers or virtual methods, is it safe to use the following? memcpy(Array1,Array2,PageSize*sizeof(MyClass)); The reason I ask, is that I'm dealing with very large collections of paged data, as decribed here, where performance is critical, and memcpy offers significant performance advantages over iterative assignment. I suspect it should be ok, as the 'this' pointer is an implicit parameter rather than anything stored, but are there any other hidden nasties I should be aware of?

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• user related commands hang on open("/etc/localtime", O_RDONLY) = 4 in CentOS 5.5

  - by fuzzy lollipop

  I am logged in as root when doing a strace -etrace=open adduser git it hangs on open("/etc/localtime", O_RDONLY) = 4 for like 2 minutes then continues on. Also when I try and strace -etrace=open su git it just hangs at the same place as well, I can't login via ssh as the git user either. Some other users I created work just fine, like su tomcat and I can ssh in as tomcat as well. I deleted the file that was at /etc/localtime and replaced it with a symlink to ln -s /usr/share/zoneinfo/US/Eastern /etc/localtime and it didn't change the behavior in any way.

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• Double null-terminated string

  - by wengseng

  I need to format a string to be double null-terminated string in order to use SHFileOperation. Interesting part is i found one of the following working, but not both: // Example 1 CString szDir(_T("D:\\Test")); szDir = szDir + _T('\0') + _T('\0'); // Example 2 CString szDir(_T("D:\\Test")); szDir = szDir + _T("\0\0"); //Delete folder SHFILEOPSTRUCT fileop; fileop.hwnd = NULL; // no status display fileop.wFunc = FO_DELETE; // delete operation fileop.pFrom = szDir; // source file name as double null terminated string fileop.pTo = NULL; // no destination needed fileop.fFlags = FOF_NOCONFIRMATION|FOF_SILENT; // do not prompt the user fileop.fAnyOperationsAborted = FALSE; fileop.lpszProgressTitle = NULL; fileop.hNameMappings = NULL; int ret = SHFileOperation(&fileop); Does anyone has idea on this? Is there other way to append double-terminated string?

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• Basic help needed with pointers

  - by sbsp

  Hi, i asked some time ago on an account i cant remember how to manipulate basic pointers and someone gave me a really good demo for example char *ptr = hello (hello = a char array) so now *ptr is pointing at h ptr++ = moves the ptr to point at the next element, to get its value i do *ptr and that gives me e ok so far i hope :D but now i need to manipulate a char **ptr and was wondering how i do this in a way that mimmicks the effects of a 2d array? some basic tips would be much appreciated as i need to do an assignment that has a **ptr to immitate a 2d array and without knowing how it does this first means i cant even solve it on paper (for example, how do you dereference a **ptr, how do you get [x][y] values etc) thanks

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• Right solution for /etc/hosts file reset on reboot

  - by user846226

  i've just installed funtoo and after setting the FQDN on /etc/conf.d/hostname i noticed when setting a list of aliases in /etc/hosts file it get overwtiten on each reboot. Someone points to set the aliases to 127.0.0.2 ip address but that's not a valid solution for me. Could someone point me to the file where i should place entries like 127.0.0.1 local.foo 127.0.0.1 local.bar in order to make them persist in /etc/hosts after rebooting? Thanks! PD: I think openresolv could be the one who is overwritting the file.

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• Basic help needed with pointers (double indirection)

  - by sbsp

  Hi, i asked some time ago on an account i cant remember how to manipulate basic pointers and someone gave me a really good demo for example char *ptr = "hello" (hello = a char array) so now *ptr is pointing at h ptr++ = moves the ptr to point at the next element, to get its value i do *ptr and that gives me e ok so far i hope :D but now i need to manipulate a char **ptr and was wondering how I do this in a way that mimmicks the effects of a 2d array? some basic tips would be much appreciated as I need to do an assignment that has a **ptr to imitate a 2d array and without knowing how it does this first means I cant even solve it on paper (for example, how do you dereference a **ptr, how do you get [x][y] values etc) thanks

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• c++ signatures, pointers

  - by coubeatczech

  Hello, what's the difference between these signatures? T * f(T & identifier); T & f(T & identifier); T f(T & identifier); void f(T * identifier); void f(T & identifier); void f(T identifier); I met pointers in c, but the amperstand in function signature is new for me. Can Anyone explain this?

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• Why do they initialize pointers this way?

  - by Rob

  In almost all of the books I read and examples I go through I see pointers initialized this way. Say that I have a class variable NSString *myString that I want to initialize. I will almost always see that done this way: -(id)init { if (self = [super init]) { NSString *tempString = [[NSString alloc] init]; myString = tempString; [tempString release]; } return self; } Why can't I just do the following? -(id)init { if (self = [super init]) { myString = [[NSString alloc] init]; } return self; } I don't see why the extra tempString is ever needed in the first place, but I could be missing something here with memory management. Is the way I want to do things acceptable or will it cause some kind of leak? I have read the Memory Management Guide on developer.apple.com and unless I am just missing something, I don't see the difference.

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