ATL / WTL / STL

Re: What is the difference between delete[] and delete?

10-Feb-03 2:24

Use delete[] when freeing dynamically allocated arrays created like this:

int * p= new int[1024]; //array of 1024 ints

and delete for every other use of new. Rule of thumb: use brackets in delete if and only if brackets where used in the corresponding new.

Joaquín M López Muñoz
Telefónica, Investigación y Desarrollo

George210-Feb-03 2:35

Re: What is the difference between delete[] and delete?

10-Feb-03 2:35

Thanks, Joaquín buddies!

I can hardly imagine a case where I should use
delete without brackets.

Can you show me an example?

Cheers,
George

Joaquín M López Muñoz10-Feb-03 2:44

Re: What is the difference between delete[] and delete?

10-Feb-03 2:44

Imagine harder Smile | :)

Never used new without brackets ([ and ])?

Joaquín M López Muñoz
Telefónica, Investigación y Desarrollo

George210-Feb-03 3:00

Re: What is the difference between delete[] and delete?

10-Feb-03 3:00

Hi, Joaquín buddies!

If a use new to allocate an object, should I use delete
to remove it?

For example,

--------
SomeType* p = new SomeType()
delete p;
--------

Am I correct?

Thanks in advance,
George

Joaquín M López Muñoz10-Feb-03 3:49

Re: What is the difference between delete[] and delete?

10-Feb-03 3:49

You are correct.

I think you will benefit a lot from reading some introductory stuff to C++. Marshall Cline's C++ FAQ Lite[^] is an excellent site to start with.

Joaquín M López Muñoz
Telefónica, Investigación y Desarrollo

George210-Feb-03 18:02

STL remove_copy_if is not working properly

10-Feb-03 18:02

Thanks, Joaquín buddies!

George

George210-Feb-03 1:15

Re: STL remove_copy_if is not working properly

10-Feb-03 1:15

Hi, everyone!

Here is my simple STL program, it is a spell-checker.
The program copy every word of text to output
that is not in the dictionary. I have added all the source
codes and error messages below. My IDE is VC6.0.
I put "abc 123 def" in c:\\dict.txt and "123 345" in c:\\words.txt.
The output should be 345, but now the output is 123 345.

Who can tell me where the error is?

Source Codes:

--------
#pragma warning(disable : 4786)

#include <iostream>
#include <algorithm>
#include <iterator>
#include <vector>
#include <fstream>
#include <string>

using namespace std;

template <class bidirectional_iterator, class T>
class nonAssocFinder {
public:
nonAssocFinder(bidirectional_iterator begin,
bidirectional_iterator end) :
_begin(begin), _end(end) {}

bool operator() (const T& word) {
cout << binary_search(_begin, _end, word);
return binary_search(_begin, _end, word); }

private:
bidirectional_iterator _begin;
bidirectional_iterator _end;
};

void main()
{
typedef vector<string> dict_type;

ifstream dictFile("c:\\dict.txt");
ifstream wordsFile("c:\\words.txt");

dict_type dictionary;

copy (istream_iterator<string>(dictFile),
istream_iterator<string>(),
back_inserter(dictionary));

remove_copy_if (
istream_iterator<string>(wordsFile),
istream_iterator<string>(),
ostream_iterator<string>(cout, "\n"),
nonAssocFinder<dict_type::iterator,
dict_type::value_type>
(dictionary.begin(), dictionary.end()));
}
--------

Thanks in advance,
George

Joaquín M López Muñoz10-Feb-03 9:29

Re: STL remove_copy_if is not working properly

10-Feb-03 9:29

binary_search assumes the range being searched is ordered. Insert this line before remove_copy_if:

sort(dictionary.begin(),dictionary.end());

and the program will work just fine.

Joaquín M López Muñoz
Telefónica, Investigación y Desarrollo

George210-Feb-03 18:00

Compiling error on my simple STL spell-checker.

10-Feb-03 18:00

Thanks, Joaquín buddies!

George

George29-Feb-03 2:39

Re: Compiling error on my simple STL spell-checker.

9-Feb-03 2:39

Hi, everyone!

Here is my simple STL program, it is a spell-checker.
The program copy every word of text to output
that is not in the dictionary. I have added all the source
codes and error messages below. My IDE is VC6.0.

Source Codes:

--------
#include <iostream>
#include <algorithm>
#include <cstring>
#include <vector>
#include <fstream>

using namespace std;

template <class bidirectional_iterator, class T>
class nonAssocFinder {
public:
nonAssocFinder(bidirectional_iterator begin,
bidirectional_iterator end) :
_begin(begin), _end(end) {}

bool operator() (const T& word) {
return binary_search(_begin, _end, word); }

private:
bidirectional_iterator _begin;
bidirectional_iterator _end;
};

void main()
{
typedef vector<string > dict_type;

ifstream dictFile("dict.txt");
ifstream wordsFile("words.txt");

dict_type dictionary;

copy (istream_iterator<string>(dictFile),
istream_iterator<string>(),
back_inserter(dictionary));

remove_copy_if (
istream_iterator<string>(wordsFile),
istream_iterator<string>(),
ostream_iterator<string>(cout, "\n"),
nonAssocFinder<dict_type::iterator,
dict_type::value_type>
(dictionary.begin(), dictionary.end()));
}
--------

Warning and error messages:
--------
C:\Program Files\Microsoft Visual Studio\MyProjects\testDict\testDict.cpp(45) : warning C4786:

'std::reverse_iterator<std::basic_string<char,std::char_traits<char>,std::allocator<char> > const

*,std::basic_string<char,std::char_traits<char>,std::all
ocator<char> >,std::basic_string<char,std::char_traits<char>,std::allocator<char> > const

&,std::basic_string<char,std::char_traits<char>,std::allocator<char> > const *,int>' : identifier was truncated to '255'

characters in the debug information
C:\Program Files\Microsoft Visual Studio\MyProjects\testDict\testDict.cpp(45) : warning C4786:

'std::reverse_iterator<std::basic_string<char,std::char_traits<char>,std::allocator<char> >

*,std::basic_string<char,std::char_traits<char>,std::allocator
<char> >,std::basic_string<char,std::char_traits<char>,std::allocator<char> >

&,std::basic_string<char,std::char_traits<char>,std::allocator<char> > *,int>' : identifier was truncated to '255' characters

in the debug information
c:\program files\microsoft visual studio\vc98\include\iterator(176) : error C2679: binary '>>' : no operator defined which

takes a right-hand operand of type 'class std::basic_string<char,struct std::char_traits<char>,class std::allocator<char> >'

(
or there is no acceptable conversion)
c:\program files\microsoft visual studio\vc98\include\iterator(176) : while compiling class-template member function

'void __thiscall std::istream_iterator<class std::basic_string<char,struct std::char_traits<char>,class std::allocator<char>
>,char,struct std::char_traits<char> >::_Getval(void)'
--------

How to resolve the trouble?

Thanks in advance,
George

Joaquín M López Muñoz9-Feb-03 11:23

Re: Compiling error on my simple STL spell-checker.

9-Feb-03 11:23

The warning is a problem with the compiler not being able to cope with the very long symbol names generated when instantiating STL containers. You can safely mask it by inserting

#pragma warning(disable: 4786)

at the beginning of your file. As for the second problem, I'm not 100% sure but probably inserting

#include <string>

will help. Good luck.

Joaquín M López Muñoz
Telefónica, Investigación y Desarrollo

George210-Feb-03 1:10

Re: Manta Web ATL Sample.

10-Feb-03 1:10

Thanks, Joaquín buddies!

George

Manta Web ATL Sample.

Bo Hunter7-Feb-03 11:14

Bo Hunter

7-Feb-03 11:14

I am tring to get this Manta Web sample to work. It does to start with
but when I try to create a new account it gives the error
OLE DB ERROR:
CAddUser::OpenRowset() returned: 0x80004005

Here is the code.

HTTP_CODE AddUser()
{
// Add the user to the database
CAddUser addUser;
lstrcpy(addUser.m_szFirstName, m_strFirstName);
lstrcpy(addUser.m_szLastName, m_strLastName);
lstrcpy(addUser.m_szEmail, m_strEmail);
lstrcpy(addUser.m_szLogin, m_strLogin);
lstrcpy(addUser.m_szHint, m_strHint);

HRESULT hr;

// don't store the real password. only store a one-way encrypted hash
DWORD dwSaltLen = 4;
DWORD dwPasswordLen = DB_MAX_STRLEN;
hr = HashSecret(
(const BYTE*) (LPCSTR) m_strPassword1, m_strPassword1.GetLength(),
(BYTE*) addUser.m_szSalt, dwSaltLen,
(BYTE*) addUser.m_szPassword, dwPasswordLen);
if (FAILED(hr))
return HTTP_FAIL;

addUser.m_szSalt[dwSaltLen] = 0;
addUser.m_szPassword[dwPasswordLen] = 0;

hr = addUser.OpenRowset(m_dataConnection, NULL);
if (hr != S_OK)
return DatabaseError("CAddUser::OpenRowset()", hr);

// Send the confirmation email
#if defined(SEND_CONFIRMATION_MAIL)
if (!SendMail())
return SMTPError();
#endif

// Create the MantaWeb persistant cookie
WritePersistCookie(addUser.m_szLogin, addUser.m_szFirstName, (m_bRememberPass) ? "1" : "0");

// Send the response page
CString strHTML;
LoadHtmlFromResource(MAKEINTRESOURCE(IDR_CONFIRM), strHTML);
strHTML.Replace("[NAME]", m_strFirstName);
strHTML.Replace("[EMAIL]", m_strEmail);
strHTML.Replace("[LOGIN]", m_strLogin);
m_HttpResponse << strHTML;
m_HttpResponse.Flush();

return HTTP_SUCCESS_NO_PROCESS;
}

It gives trouble at hr = addUser.OpenRowset(m_dataConnection, NULL);
It returns FAIL.

Thank You
Bo Hunter

Bo Hunter

TigerNinja_19-Feb-03 3:18

TigerNinja_

19-Feb-03 3:18

I could not even get this example to compile. I downloaded it directly from Microsoft and have the current SDK, and VS.NET, however, it wouldn't compile.

this sample is evil, manta web is evil. Laugh | :laugh:

R.Bischoff | C++

.NET, Kommst du mit?

resume download

Anonymous6-Feb-03 17:34

Anonymous

6-Feb-03 17:34

Hi,

I am working on the application wherein i have to download the file from the URL mentioned.

But the problem is I have to support the resume operations for broken downloads...using mfc.
How do i do this using mfc. Please give me your inputs.

TIA,
Snowy

Re: resume download

JoeSox6-Feb-03 19:02

JoeSox

6-Feb-03 19:02

I would start with MFC class CInternetSession.
I would prepare a CString(which creates a temp file on harddrive if Isesion stops) and download the html, have it write to the string in chunks and always GetLengh() so if the download stops, you know where to resume later.

I don't have any professional experience with this type of thing but I have used the CInternetSession. That's where I would start, I don't know if it's the best logic though. Ask for a second opinion, if you have time Big Grin | :-D

Later,
JoeSox
www.joeswammi.com

Load my Sig here.....

Re: resume download

AlexO7-Feb-03 3:05

AlexO

7-Feb-03 3:05

This ATL/WTL/STL forum so my suggestion is to use ATL for it. I believe it could be safely mixed with MFC. ATL class CBindStatusCallback does most of what you are looking for.

Re: resume download

Todd Smith19-Feb-03 9:29

Todd Smith

19-Feb-03 9:29

You have to add a Range: header to your download request. Lets say you got 1000 bytes of a file from a previous request. Here's what you need to do

GET /somefile.zip HTTP/1.1
Range: bytes=1000-

which will start at offset 1000 bytes into the file.

Todd Smith

outlook express configuration

naradaji6-Feb-03 5:25

naradaji

6-Feb-03 5:25

Hi,
I'm writing a program that is supposed to detect the configuration of outlook express (installed in the machine where the application is run). When I say configuration I mean the pop and smtp servers, at least. Now, reading the registry I can get that info, but the registry keys vary according to the user (right?), because different user profiles (windows 2000) can have different outllo express configurations. What I really need is to detect the configuration for the user that is executing the application.
For Example, my reg key for this is in:
HKEY_USERS\S-1-5-21-3046562155-3082545408-3971354878-2339\Software\Microsoft\Internet Account Manager\Accounts\00000001

Now, what is this number: "S-1-5-21-3046562155-3082545408-3971354878-2339"? I don't think it's going to be the same in different machines, therefore I don't seem to be able to detect what I want using the registry.

Any ideas?

Thanks!

-- narada

Michael Dunn6-Feb-03 9:43

Michael Dunn

6-Feb-03 9:43

That's what HKEY_CURRENT_USER is for, it's mapped to the current user's key in HKEY_USERS.

--Mike--
The Internet is a place where absolutely nothing happens.
-- Strong Bad

1ClickPicGrabber - Grab & organize pictures from your favorite web pages, with 1 click!
My really out-of-date homepage
Sonork-100.19012 Acid_Helm

naradaji6-Feb-03 21:13

naradaji

6-Feb-03 21:13

Sorry, this is wrong forum, right? Anyway, I appreciate your answer, still I don't know if the key is going to be the same in another machine, so how could read that programmatically?

Thanks anyway,

-- narada

Michael Dunn8-Feb-03 19:09

Michael Dunn

8-Feb-03 19:09

From your first post (with my emphasis):

What I really need is to detect the configuration for the user that is executing the application.

Again, that is what HKEY_CURRENT_USER is for. The system automatically maps that hive to the key under HKEY_USERS that corresponds to the user making the call. You never have to access HKEY_USERS at all.

--Mike--
The Internet is a place where absolutely nothing happens.
-- Strong Bad

1ClickPicGrabber - Grab & organize pictures from your favorite web pages, with 1 click!
My really out-of-date homepage
Sonork-100.19012 Acid_Helm