C / C++ / MFC Discussion Boards

varunpandeyengg9-May-11 22:21

9-May-11 22:21

You may do some reverse engineering to get String from CRC. Although that's not feasible. CRC produce unique set of bytes for any data (in your case it is string). As you mentioned correctly, it may not be Unique. The process is slow unless you know how to optimize it.
One more method is to use MD5 or SHA1. Although the whole purpose of MD5 is to authenticate the data (and it uses Hash function - which may take extra clock cycles), it can also be used smartly to replace CRC. There is a exhaustive list of error-correcting algorithm which I am not mentioning here. Pick any of those according to the importance of the transfered data.

(CRC converts data => Checksums so the only way we can get data be CRC is by trial and error)

CHEERS!!!

Problem with VC toolbox

Cold_Fearing_Bird8-May-11 16:47

Cold_Fearing_Bird

8-May-11 16:47

What's the major purpose for the "Customize the toolbox"? As far as I know I can put text in the toolbox to facilitate some coding, is it possible to put a "Color picker"(Color dialog box as in photoshop) in the toolbox?

Re: Problem with VC toolbox

Hans Dietrich8-May-11 17:01

Hans Dietrich

8-May-11 17:01

See here: http://msdn.microsoft.com/en-us/library/dyca0t6t%28v=VS.100%29.aspx[^]

Best wishes,
Hans

[Hans Dietrich Software]

Max++8-May-11 14:06

Max++

8-May-11 14:06

My software need to use MMC control and run on Windows7.
but when I try to register MCI32.ocx by bat file that include the code "@echo off regsvr32 MCI32.ocx" I've got some error
"The module "MCI32" was loaded but the call to DllRegisterServer failed with error code 0x8002801c"

I have used in Windows XP and never seen this problem before.

Please anybody help me to solve this problem.

Re: Register ocx in Windows7

Richard Andrew x648-May-11 14:20

Richard Andrew x64

8-May-11 14:20

I put "0x8002801c" into Google and a treasure trove of pages came up.

The difficult we do right away...
...the impossible takes slightly longer.

Re: Register ocx in Windows7

pandit848-May-11 21:10

pandit84

8-May-11 21:10

Please try to run the command prompt as "Run as Administrator" and then run the batch file.

Re: Register ocx in Windows7

Malli_S9-May-11 0:41

Malli_S

9-May-11 0:41

This is regarding privilege to access Registry. The error code "0x8002801c" (Error accessing the OLE registry) says that you don't have write permission to the registry. You may have to run the bat file with high privilege, to do so run the bat file by right clicking on file and selecting 'Run as administrator' option.

[Delegates] [Virtual Desktop] [Tray Me !]

-Malli...!

Re: Register ocx in Windows7

Max++9-May-11 15:12

Max++

9-May-11 15:12

Thanks a lot everybody

"Ending program ... please wait" - what system message needs a response ?

Still learning how to code8-May-11 8:56

Still learning how to code

8-May-11 8:56

I have a home-made app which performs fine, until the system is rebooted/restarted. Then I get the message "Ending program ... please wait", a timeout occurs, and then the app ends. As this is the only app which responds in this way, I assume that I have not coded the response to a system message which is causing the timeout. What system message is being sent and what response should be made to cause immediate termination ? Thanks in advance !

Doug

Re: "Ending program ... please wait" - what system message needs a response ?

Code-o-mat8-May-11 9:28

Code-o-mat

8-May-11 9:28

Not completely sure but maybe what you need is WM_QUERYENDSESSION[^] or WM_ENDSESSION[^]? This[^] here might also be useful to read.

> The problem with computers is that they do what you tell them to do and not what you want them to do. <
> //TODO: Implement signature here<

Re: "Ending program ... please wait" - what system message needs a response ?

Luc Pattyn8-May-11 9:45

Luc Pattyn

8-May-11 9:45

AFAIK a Windows app will get terminated automatically if it is a WinForms app (hence a message pump is active) with proper event handling (always responsive, so no long-winding event handlers), AND no extra threads are running in the foreground. If you need background activity, I recommend you mark your threads background ones, so they don't prevent app shutdown.

Smile | :)

Luc Pattyn [Forum Guidelines] [My Articles] Nil Volentibus Arduum

Please use <PRE> tags for code snippets, they preserve indentation, improve readability, and make me actually look at the code.

Re: "Ending program ... please wait" - what system message needs a response ?

Still learning how to code8-May-11 11:16

Still learning how to code

8-May-11 11:16

Found the "problem" ! (Embarresing really !) I wrote this app a long time ago and used a dialog-based MFC app but prevented the dialog appearing so that it effectively ran in the background. The main "routine" was in InitDialog() and effectively prevented messages being handled by the "window". Now create a thread in InitDialog(), let it complete, and hide the window in another way. WM_QUERYENDSESSION is now handled, and all works fine ! Thanks for your thought-provoking comments !! Smile | :)

Doug

application messaging

Krauze7-May-11 22:20

Krauze

7-May-11 22:20

I'm currently coding on a project where I need to post a user-defined message together with a LPCWSTR parameter.
But I don't know how to achieve that coz you know, PostMessage() only provides parameters typed as WPARAM and LPARAM.
Anyone could help?
Many thx in advance.

Re: application messaging

Richard MacCutchan7-May-11 23:33

Richard MacCutchan

7-May-11 23:33

Cast[^] your string to LPARAM and do the reverse at the receiving end.

The best things in life are not things.

Re: application messaging

barneyman7-May-11 23:51

barneyman

7-May-11 23:51

but be aware that if your string is transient ((new'd and delete'd) or stack based), it'll possibly be corrupt at the other end if you PostMessage it ...

Re: application messaging

Richard MacCutchan8-May-11 0:08

Richard MacCutchan

8-May-11 0:08

I'm well aware of that. However, if the OP is not aware of casting then I doubt he'll be into something as advanced as new and delete. Wink | ;)

The best things in life are not things.

Re: application messaging

David Crow9-May-11 3:16

David Crow

9-May-11 3:16

barneyman wrote:
but be aware that if your string is transient ((new'd and delete'd) or stack based), it'll possibly be corrupt at the other end if you PostMessage it ...

How so? In order to pass strings from one thread to another using PostMessage(), new and delete are highly recommended.

"One man's wage rise is another man's price increase." - Harold Wilson

"Fireproof doesn't mean the fire will never come. It means when the fire comes that you will be able to withstand it." - Michael Simmons

"Some people are making such thorough preparation for rainy days that they aren't enjoying today's sunshine." - William Feather

Re: application messaging

barneyman9-May-11 3:39

barneyman

9-May-11 3:39

true; got me

Re: application messaging

Code-o-mat8-May-11 9:35

Code-o-mat

8-May-11 9:35

Let's hope both the sending and receiving end is in the same process-space.

> The problem with computers is that they do what you tell them to do and not what you want them to do. <
> //TODO: Implement signature here<

lzma on GPU

crotaphiticus7-May-11 20:12

crotaphiticus

7-May-11 20:12

guys, any clue if LZMA could be parallelized to be run in some way that makes it worth being run on a GPU rather than over a CPU?

The idea is to compress text.

Also: which would be better : ctw or lzma ?

thanks

Re: lzma on GPU

Code-o-mat8-May-11 6:22

Code-o-mat

8-May-11 6:22

Don't know much about compression algorithsm and somesuch but to make the GPU do things for you i would look into programmable pixel/vertex shaders, CUDA[^] and ATI Stream[^], maybe one of those can help you get started.

> The problem with computers is that they do what you tell them to do and not what you want them to do. <
> //TODO: Implement signature here<

Re: lzma on GPU

crotaphiticus8-May-11 7:54

crotaphiticus

8-May-11 7:54

thx man. There is already a bzip cuda project but none that uses LZMA

Re: lzma on GPU

Code-o-mat8-May-11 9:39

Code-o-mat

8-May-11 9:39

If it is opensource then i guess checking it out can help learn how you could use it for LZMA. Just note that -as far as i know- CUDA works only on (newer?) nVidia cards and ATI Stream on (also newer?) ATI cards, so if you write a CUDA-based LZMA compressor/decompressor, it won't work on a computer which has an ATI or some intel-integrated graphics system. Correct me if i am wrong though.

> The problem with computers is that they do what you tell them to do and not what you want them to do. <
> //TODO: Implement signature here<

Re: lzma on GPU

crotaphiticus8-May-11 12:33

crotaphiticus

8-May-11 12:33

Makes lots of sense. Here its one sample ( regarding what you mean). I placed the words dot instead of the "." to avoid being considered spam Smile | :)

http://bzip2-cuda.github dot com/[^]

about multi linked list

quartaela7-May-11 9:44

quartaela

7-May-11 9:44

hi there i have discussed my problems about multi linked list thread
http://www.codeproject.com/Messages/3876300/implementing-multi-linked-list-correctly_.aspx

but i recognize that it coldn't solved. my problem was about implementing a multi linked list which your list implemented by more than one cases. for example by first name or last name. so it have two header and tail pointers. the adding and building the list operations are succesfully working. and there is not a problem when i delete a node by "first_name" and when i search him again, the output is "not found". but when i search him by his "last_name" (so i using header pointer of last name here) the output becomes "person exist". i hope i explain my problem understandable : ). so i appreciated if you can help me.

here is my structures

typedef struct node {

    int birth_date;
    int zipcode;
    int phone_num;
    char first_name[50];
    char last_name[50];
    char city[50];
    char address[50];
    char email_addr[50];

    struct node* fn_next;
    struct node* fn_pre;
    struct node* ln_next;
    struct node* ln_pre;
    struct node* birdat_next;
    struct node* birdat_pre;

} NODE;

typedef struct {

    int fn_count;
    int ln_count;

    NODE* fn_head;
    NODE* ln_head;
    
    NODE* fn_tail;
    NODE* ln_tail;

}LIST;

and here is the block i call adding functions for name and surname;

while ( !feof(myfile) ) {

        NODE* pnew_stu;

        if( !(pnew_stu = (NODE*) malloc(sizeof(NODE))) ) {

            printf("ERROR NOT ENOUGH MEMORY!!!\n");
            exit(100);
        }

        fscanf(myfile,"%s", &(pnew_stu->first_name) );
        fscanf(myfile,"%s", &(pnew_stu->last_name) );
        fscanf(myfile,"%s", &(pnew_stu->email_addr) );
        fscanf(myfile,"%d", &(pnew_stu->phone_num) );
        fscanf(myfile,"%s", &(pnew_stu->address) );
        fscanf(myfile,"%s", &(pnew_stu->city) );
        fscanf(myfile,"%d", &(pnew_stu->zipcode) );

        add_fn_Node(list,pnew_stu);
        add_ln_Node(list,pnew_stu);

}

and of course my add functions;

void add_fn_Node(LIST* list, NODE* pnew_stu) {

    NODE* temp = list->fn_head;

    if( list->fn_head == NULL ) {

            pnew_stu->fn_next = list->fn_head;
            pnew_stu->fn_pre = list->fn_head;


            list->fn_head = pnew_stu;

            list->fn_count = 1;

            return;

        }

        else {

            temp = list->fn_head;

            if ( (strcmp( pnew_stu->first_name, temp->first_name )) <= 0 ) { // Condition for add before the first node

                pnew_stu->fn_next = temp;
                pnew_stu->fn_pre = temp->fn_pre;
                temp->fn_pre = pnew_stu;

                list->fn_head = pnew_stu;

                list->fn_count++;

                return;

            }

            else {
                
                 while ( temp->fn_next != NULL ) { // Condition for add middle

                        if ( (strcmp( pnew_stu->first_name, temp->first_name ) >= 0 ) && (strcmp( pnew_stu->first_name, temp->fn_next->first_name) < 0)) {

                        pnew_stu->fn_next = temp->fn_next;
                        pnew_stu->fn_pre = temp;
                        temp->fn_next->fn_pre = pnew_stu;
                        temp->fn_next = pnew_stu;

                        list->fn_count++;

                        return;
                    }

                        temp = temp->fn_next;

                    }

                if ( temp->fn_next == NULL ) { // Condition for add to end

                    temp->fn_next = pnew_stu;
                    pnew_stu->fn_pre = temp;
                    pnew_stu->fn_next = NULL;

                    list->fn_tail = pnew_stu;

                    list->fn_count++;

                    return;

                }
            }

        }
}

void add_ln_Node(LIST* list, NODE* pnew_stu) {

    NODE* temp = list->ln_head;

    if( list->ln_head == NULL ) {

            pnew_stu->ln_next = list->ln_head;
            pnew_stu->ln_pre = list->ln_head;


            list->ln_head = pnew_stu;

            list->ln_count = 1;

            return;

        }

        else {

            temp = list->ln_head;

            if ( (strcmp( pnew_stu->last_name, temp->last_name )) <= 0 ) { // Condition for add before the first node

                pnew_stu->ln_next = temp;
                pnew_stu->ln_pre = temp->ln_pre;
                temp->ln_pre = pnew_stu;

                list->ln_head = pnew_stu;

                list->ln_count++;

                return;

            }

            else {


                 while ( temp->ln_next != NULL ) { //Condition for add middle

                        if ( (strcmp( pnew_stu->last_name, temp->last_name ) >= 0 ) && (strcmp( pnew_stu->last_name, temp->ln_next->last_name) < 0)) {

                        pnew_stu->ln_next = temp->ln_next;
                        pnew_stu->ln_pre = temp;
                        temp->ln_next->ln_pre = pnew_stu;
                        temp->ln_next = pnew_stu;
                        
                        list->ln_count++;

                        return;
                    }

                        temp = temp->ln_next;

                    }

                if ( temp->ln_next == NULL ) { // Condition for add to end

                    temp->ln_next = pnew_stu;
                    pnew_stu->ln_pre = temp;
                    pnew_stu->ln_next = NULL;

                    list->ln_tail = pnew_stu;

                    list->ln_count++;

                    return;

                }
            }

        }
}

Use Ctrl+Left/Right to switch messages, Ctrl+Up/Down to switch threads, Ctrl+Shift+Left/Right to switch pages.