[win32] temp and preference path on windows

[THEARTOFWEB]

Hi,

I was searching a place in the windows filesystem to save a preference file. I have found out that onmy system (vista) that place is supposed to be:

Pref: \Users\MY_ACCOUNT\AppData\Local

Also, I'd like to know if the following is the correct path to a %temp% directory to save some file for the running session to be delete at the end of the session:

Temp: \Users\MY_ACCOUNT\AppData\Local\Temp

Do you think I could retrieve those paths with some API function?

thanks

[krmed]

You could begin by opening a command window and looking at the environment variables. (From the command prompt type "set" - without the quotes). You'll find variables like

APPDATA
HOMEPATH
TEMP
USERPROFILE

and so on. You can then use GetEnvironmentVariable to get those values.

Hope that helps.

[VictorN]

...
Do you think I could retrieve those paths with some API function?

Yes!
SHGetKnownFolderPath Function
KNOWNFOLDERID
or
SHGetFolderPath Function
CSIDL

[THEARTOFWEB]

Ok, I am tring this: http://msdn.microsoft.com/en-us/libr...8VS.85%29.aspx

char * fullpath;
HRESULT res = SHGetKnownFolderPath(FOLDERID_LocalAppData, 0, 0, fullpath);

I get this:

'SHGetKnownFolderPath' : cannot convert parameter 4 from 'char *' to 'PWSTR *'

how can I cast correctly?

thanks

[VictorN]

Why do you ignore what MSDN claims?
Parameter 4 must be of the type PWSTR *, not char *!

PWSTR pName;
HRESULT res = SHGetKnownFolderPath(FOLDERID_LocalAppData, 0, 0, &pName);

[THEARTOFWEB]

oh well...yeah! Yet, I'd like to normalize that to a regular string or char arrays. Infact if I do like this:

std::cout << *pName << std::endl;
// or
std::cout << pName << std::endl;

I get just numbers :-(

[Arjay]

oh well...yeah! Yet, I'd like to normalize that to a regular string or char arrays. Infact if I do like this:

std::cout << *pName << std::endl;
// or
std::cout << pName << std::endl;

I get just numbers :-(

You need to start understanding the difference between compiling for UNICODE and MBCS (ANSI). Also in what happens to CString and tchar.h typedef types under the different character sets.

[THEARTOFWEB]

Ok, sorted out this way:

#include <iostream>
#include <string>
#include <cstdlib>
#include <shlobj.h>

int main()
{
    TCHAR szPath[MAX_PATH] = {0};

    HRESULT res = SHGetFolderPath(NULL,
                                  CSIDL_LOCAL_APPDATA|CSIDL_FLAG_DONT_VERIFY,
                                  NULL,
                                  0,
                                  szPath);

    std::cout << szPath << std::endl;

    

    system("pause");
    return EXIT_SUCCESS;
}

Now, I was wondering whether there was a way to append a file path to the end of szPath. I mean, is there any function aimed to deal with slashes or is it something I can do on my own??

[Arjay]

Now, I was wondering whether there was a way to append a file path to the end of szPath. I mean, is there any function aimed to deal with slashes or is it something I can do on my own??

Yep, you can use the CString class which already knows about UNICODE/MBCS.

#include <iostream>
#include <string>
#include <cstdlib>
#include <shlobj.h>
 
#include <atlstr.h>

int main()
{
    CString sPath;

    HRESULT res = SHGetFolderPath(
      NULL,
      CSIDL_LOCAL_APPDATA | CSIDL_FLAG_DONT_VERIFY,
      NULL,
      0,
      sPath.GetBuffer( MAX_PATH );
 
    sPath.ReleaseBuffer( );
 
    sPath += _T("\\appendthis");

    std::cout << sPath.GetString( ) << std::endl;
 
    // if compiling for UNICODE...
    // std::wcout << sPath.GetString( ) << std::endl;

    system("pause");

    return EXIT_SUCCESS;
}

[THEARTOFWEB]

Ok, one more thing. Why the following fires an error?

#include <iostream>
#include <cstdlib>
#include <tchar.h>
#include <shlobj.h>
#include <shlwapi.h>

int _tmain()
{
    TCHAR szPath[MAX_PATH] = {0};

    HRESULT res = SHGetFolderPath(NULL,
                                  CSIDL_LOCAL_APPDATA|CSIDL_FLAG_DONT_VERIFY,
                                  NULL,
                                  0,
                                  szPath);

    std::cout << szPath << std::endl;

    PathAppend(szPath, TEXT("myfile.txt"));

    std::cout << szPath << std::endl;

    system("pause");
    return EXIT_SUCCESS;
}

main.obj : error LNK2019: unresolved external symbol __imp__PathAppendA@8 referenced in function _main

???

thanks

[VictorN]

Ok, one more thing. Why the following fires an error?
...
main.obj : error LNK2019: unresolved external symbol __imp__PathAppendA@8 referenced in function _main

???

Why don't you want to read the PathAppend documentation????
Please, have a look at the "Function Information section (Header and Import library)

[THEARTOFWEB]

yeah, I always miss that :-(

#pragma comment (lib, "shlwapi.lib")

thanks

[Arjay]

yeah, I always miss that :-(

#pragma comment (lib, "shlwapi.lib")

thanks

Or you could just use the CString class and eliminate about 1/3 of your string handling code.