Skip to content
  • Categories
  • Recent
  • Tags
  • Popular
  • World
  • Users
  • Groups
Skins
  • Light
  • Cerulean
  • Cosmo
  • Flatly
  • Journal
  • Litera
  • Lumen
  • Lux
  • Materia
  • Minty
  • Morph
  • Pulse
  • Sandstone
  • Simplex
  • Sketchy
  • Spacelab
  • United
  • Yeti
  • Zephyr
  • Dark
  • Cyborg
  • Darkly
  • Quartz
  • Slate
  • Solar
  • Superhero
  • Vapor

  • Default (No Skin)
  • No Skin
Collapse
Code Project
  1. Home
  2. General Programming
  3. C / C++ / MFC
  4. dlete pointer.

dlete pointer.

Scheduled Pinned Locked Moved C / C++ / MFC
question
23 Posts 7 Posters 0 Views 1 Watching
  • Oldest to Newest
  • Newest to Oldest
  • Most Votes
Reply
  • Reply as topic
Log in to reply
This topic has been deleted. Only users with topic management privileges can see it.
  • S see me

    In my case the above mentioned 4 cases will not be satisfied. Actual reason is any other.:-> And also as per ur comments int * p = NULL; delete p; how the datas will be deleted from the location which is pointed by p initialy. since u r saying to delete the pointer after asigning the pointer to null.:confused: yours faithfully ajeeshcv

    C Offline
    C Offline
    Cedric Moonen
    wrote on last edited by
    #14

    Ajeesh c v wrote:

    how the datas will be deleted from the location which is pointed by p initialy. since u r saying to delete the pointer after asigning the pointer to null.

    That's probably your problem. When you do this:

    int* pTest;
    if (pTest)
    delete pTest;

    You will have an excpetion because you try to delete memory that is unitianalized (you can only delete memory that has been allocated with new). So, to be sure not to delete this 'unexistant' memory, assign NULL to the pointer. This is safe.


    Cédric Moonen Software developer
    Charting control

    1 Reply Last reply
    0
    • S see me

      In my case the above mentioned 4 cases will not be satisfied. Actual reason is any other.:-> And also as per ur comments int * p = NULL; delete p; how the datas will be deleted from the location which is pointed by p initialy. since u r saying to delete the pointer after asigning the pointer to null.:confused: yours faithfully ajeeshcv

      V Offline
      V Offline
      Viorel
      wrote on last edited by
      #15

      According to documentation (http://msdn2.microsoft.com/en-us/library/h6227113.aspx[^]), “You can [...] use delete on a pointer with the value 0”. Therefore instead of

      if( p != NULL )
      {
          delete p;
          p = NULL;
      }
      

      you can use

      delete p;
      p = NULL;
      

      However, this does not belong to original topic. I think you should put a breakpoint at the line where your block of memory is allocated and the pointer is assigned. Then investigate the pointer’s value and the content of the memory block. Then stop on the line where the pointer is deleted. Check if the pointer contains right address value. Try to use step-be-step execution during deletion. Perhaps the pointer points to an object having destructor, and the problem is within this function.

      1 Reply Last reply
      0
      • T toxcct

        Ajeesh c v wrote:

        exception is occuring.

        DAMNNNNN !!! WHICHHHH ????? if you don't provide some descriptions of your error case, how can one help you ?? :~ :mad:


        TOXCCT >>> GEII power

        [VisualCalc 3.0  updated ][Flags Beginner's Guide  new! ]

        S Offline
        S Offline
        see me
        wrote on last edited by
        #16

        ok... I think the problem is occuring due to this reason. am initializing the pointer from thread...adn try to delete it from another thread.. if there is any chance of occuring exception???? Please help me... yours faithfully ajeeshcv

        T V J 3 Replies Last reply
        0
        • S see me

          ok... I think the problem is occuring due to this reason. am initializing the pointer from thread...adn try to delete it from another thread.. if there is any chance of occuring exception???? Please help me... yours faithfully ajeeshcv

          T Offline
          T Offline
          toxcct
          wrote on last edited by
          #17

          as far as you don't answer my questions, i don't help you furthermore. :zzz:


          TOXCCT >>> GEII power

          [VisualCalc 3.0  updated ][Flags Beginner's Guide  new! ]

          1 Reply Last reply
          0
          • C Cedric Moonen

            That's a very clear description of the problem :~ The solution is: you did something wrong.


            Cédric Moonen Software developer
            Charting control

            S Offline
            S Offline
            see me
            wrote on last edited by
            #18

            Thats a very precious information for me. Thank you.. yours faithfully ajeeshcv

            1 Reply Last reply
            0
            • S see me

              ok... I think the problem is occuring due to this reason. am initializing the pointer from thread...adn try to delete it from another thread.. if there is any chance of occuring exception???? Please help me... yours faithfully ajeeshcv

              V Offline
              V Offline
              Viorel
              wrote on last edited by
              #19

              I think this causes problems if your project’s configuration does not allow multi-threading. You should open the project’s properties dialog and be sure that the C/C++ --> Code Generation --> Runtime Library option contains a right value related to multi-threading. Then rebuild the application.

              S 1 Reply Last reply
              0
              • H Hamid Taebi

                Can you show how to use pointer and how to declare pointer_**


                **_

                whitesky


                S Offline
                S Offline
                see me
                wrote on last edited by
                #20

                The pointer is of a dialog. Initialization: CMyDialog* pMyDialog; pMyDialog = new CMyDialog; pMyDialog->EndDialog(0); if(pMyDialog) { delete pMyDialog; pMyDialog = 0; } yours faithfully ajeeshcv

                H 1 Reply Last reply
                0
                • V Viorel

                  I think this causes problems if your project’s configuration does not allow multi-threading. You should open the project’s properties dialog and be sure that the C/C++ --> Code Generation --> Runtime Library option contains a right value related to multi-threading. Then rebuild the application.

                  S Offline
                  S Offline
                  see me
                  wrote on last edited by
                  #21

                  Thank you... I don't know it will work or not. Let me check. yours faithfully ajeeshcv

                  1 Reply Last reply
                  0
                  • S see me

                    The pointer is of a dialog. Initialization: CMyDialog* pMyDialog; pMyDialog = new CMyDialog; pMyDialog->EndDialog(0); if(pMyDialog) { delete pMyDialog; pMyDialog = 0; } yours faithfully ajeeshcv

                    H Offline
                    H Offline
                    Hamid Taebi
                    wrote on last edited by
                    #22

                    im not sure your problem is this but how to create dialog? and if you run your code i think you get a error in pMyDialog->EndDialog(0); now try this and send me if you have a error CMyDialog* pMyDialog; pMyDialog = new CMyDialog; pMyDialog->Create(IDD_TEST);//id from dialog pMyDialog->EndDialog(0); delete pMyDialog ; pMyDialog = 0;_**


                    **_

                    whitesky


                    1 Reply Last reply
                    0
                    • S see me

                      ok... I think the problem is occuring due to this reason. am initializing the pointer from thread...adn try to delete it from another thread.. if there is any chance of occuring exception???? Please help me... yours faithfully ajeeshcv

                      J Offline
                      J Offline
                      jhwurmbach
                      wrote on last edited by
                      #23

                      Ajeesh c v wrote:

                      am initializing the pointer from thread...adn try to delete it from another thread

                      May one thread still be accessing the memory you just deleted? Maybe using smart-pointers (like those from boost.org)[^]can help you? Or at least an object which can delete itself via a member function?


                      "We trained hard, but it seemed that every time we were beginning to form up into teams we would be reorganised. I was to learn later in life that we tend to meet any new situation by reorganising: and a wonderful method it can be for creating the illusion of progress, while producing confusion, inefficiency and demoralisation." -- Caius Petronius, Roman Consul, 66 A.D.

                      1 Reply Last reply
                      0
                      Reply
                      • Reply as topic
                      Log in to reply
                      • Oldest to Newest
                      • Newest to Oldest
                      • Most Votes


                      • Login

                      • Don't have an account? Register

                      • Login or register to search.
                      • First post
                        Last post
                      0
                      • Categories
                      • Recent
                      • Tags
                      • Popular
                      • World
                      • Users
                      • Groups