[loverboy]

Why preferences.dat changes everytime, while cryptkey.dat remains the same since the first installation of eMule?

[SS1900]

Preferences.dat
Saves the user hash. This is a value calculated at eMule's first start and is used to identify this client in the network. Used for credit system and friends.

Cryptkey.dat
Contains the unique 384 bit private RSA key of your client to verify your userhash. If you delete this file, make sure to also delete preferences.dat which stores your userhash.

[loverboy]

So why my preferences.dat (=userhash) changes everytime I close emule? the file date changes and so its content.
Is it related to my IP in that particular session?

[SS1900]

because after an emule's session your "credits" are changed

This post has been edited by SS1900: 01 November 2009 - 11:25 AM

[Nissenice]

loverboy, on 01 November 2009 - 12:09 PM, said:

So why my preferences.dat (=userhash) changes everytime I close emule? the file date changes and so its content.
Is it related to my IP in that particular session?

No it has nothing to do with your IP. A value named PREFFILE_VERSION (which currently (v0.49c) equals 0x14), the position of eMule's window on the screen and the userhash is saved in preferences.dat each time eMule is closed.

bool CPreferences::Save(){

	bool error = false;
	CString strFullPath;
	strFullPath = GetMuleDirectory(EMULE_CONFIGDIR) + L"preferences.dat";

	FILE* preffile = _tfsopen(strFullPath, L"wb", _SH_DENYWR);
	prefsExt->version = PREFFILE_VERSION;
	if (preffile){
		prefsExt->version=PREFFILE_VERSION;
		prefsExt->EmuleWindowPlacement=EmuleWindowPlacement;
		md4cpy(prefsExt->userhash, userhash);

		error = fwrite(prefsExt,sizeof(Preferences_Ext_Struct),1,preffile)!=1;
		if (thePrefs.GetCommitFiles() >= 2 || (thePrefs.GetCommitFiles() >= 1 && !theApp.emuledlg->IsRunning())){
			fflush(preffile); // flush file stream buffers to disk buffers
			(void)_commit(_fileno(preffile)); // commit disk buffers to disk
		}
		fclose(preffile);
	}
	else
		error = true;

(...)
}

[omeringen]

loverboy, on 01 November 2009 - 01:09 PM, said:

So why my preferences.dat (=userhash) changes everytime I close emule? the file date changes and so its content.
Is it related to my IP in that particular session?

Your ID is related with your WAN ip number, not userhash. I think preferences.dat file content is always the same. Maybe eMule is reading it from the memory and rewriting it to the disk on close action.

SS1900, on 01 November 2009 - 01:23 PM, said:

because after an emule's session your "credits" are changed

I couldn't understand that message. . .

//Nissenice has already posted while i was writing

This post has been edited by omeringen: 01 November 2009 - 12:16 PM

[SS1900]

omeringen, on 01 November 2009 - 01:14 PM, said:

SS1900, on 01 November 2009 - 01:23 PM, said:

because after an emule's session your "credits" are changed

I couldn't understand that message. . .

yeah i'm wrong

[xilolee]

if

Quote

preferences.dat file content is always the same

why should emule rewrite it?

This post has been edited by xilolee: 01 November 2009 - 01:10 PM

[omeringen]

File content is always the same, eMule is just rewriting it. Don't know the tech explanation, maybe devs or someone who knows how to read the code can answer

[xilolee]

precisely ... if the content does not change, it should not to be rewrited and have the same date of the criptkey.dat (mine has 19/12/2006)

[Nissenice]

xilolee, on 01 November 2009 - 02:30 PM, said:

precisely ... if the content does not change, it should not to be rewrited and have the same date of the criptkey.dat (mine has 19/12/2006)

Have you 'Safe .met/.dat file writing' set to 'Never' in Options->Extended?

[omeringen]

@Nissenice,
cryptkey.dat file is not the point because eMule doesn't rewrite it even if you set "Safe .met/.dat file writing" option to "Always". . . For example mine is about 2008.

This post has been edited by omeringen: 01 November 2009 - 01:51 PM

[xilolee]

@nissenice

yes, but i have modified that option in the last months, whilst in the 2006 i had the default option (on shutdown)

[Nissenice]

omeringen, on 01 November 2009 - 02:41 PM, said:

@Nissenice,
cryptkey.dat file is not the point because eMule doesn't save it even if you set "Safe .met/.dat file writing" option to "Always". . . For example mine is about 2008.

Well, I wasn't thinking of cryptkey.dat. I thought what xilolee was trying to say was that his preferences.dat was last changed the same date as his cryptkey.dat.

And if so the only reason for this would be this part from the code posted above:

		if (thePrefs.GetCommitFiles() >= 2 || (thePrefs.GetCommitFiles() >= 1 && !theApp.emuledlg->IsRunning())){
			fflush(preffile); // flush file stream buffers to disk buffers
			(void)_commit(_fileno(preffile)); // commit disk buffers to disk
		}

Which basically says, if I'm not wrong, that if 'Safe .met/.dat file writing' is set to 'Always' preferences.dat will always be saved at shutdown and if it is set to 'Never' it never will.


Btw, my preferences.dat changes every time I close the program. And I have "Safe .met/.dat file writing" set to 'On shutdown'

[Nissenice]

xilolee, on 01 November 2009 - 02:50 PM, said:

@nissenice

yes, but i have modified that option in the last months, whilst in the 2006 i had the default option (on shutdown)

Hmm.. Strange! That was unexpected. Perhaps you are using a backup of it?

This post has been edited by Nissenice: 01 November 2009 - 02:11 PM

[xilolee]

Now i have modified the safe met/dat in always - restarted and connected emule twice and the criptkey is always since 2006

This post has been edited by xilolee: 01 November 2009 - 02:16 PM

[omeringen]

Why unexpected ? I have just told my file's "date modified" date is about 02/2008 ;

omeringen, on 01 November 2009 - 03:41 PM, said:

@Nissenice,
cryptkey.dat file is not the point because eMule doesn't rewrite it even if you set "Safe .met/.dat file writing" option to "Always". . . For example mine is about 2008.

This post has been edited by omeringen: 01 November 2009 - 02:16 PM

[Nissenice]

xilolee, on 01 November 2009 - 03:15 PM, said:

Now i have modified the safe met/dat in always - restarted and connected emule twice and the criptkey is always since 2006

criptkey? I thought we were discussing preferences.dat here.

[xilolee]

imo, if the preferences.dat and the criptkey.dat do not change, they should not be rewrited ... but the preferences.dat changes

This post has been edited by xilolee: 01 November 2009 - 02:22 PM

[torpon]

User hash is 16 bytes long, whilw preferences.dat is 56 bytes long. So is clear that it stores something more than user hash.

Cheers +-