|
impossible.
post a relevant piece of code please.
|
|
|
|
|
toxcct wrote: impossible.
Yes, if UNICODE is defined.
|
|
|
|
|
CString strFName = m_FName + CString(data);
FILE* fp = fopen((LPCTSTR)strFName,"wb");
Its giving error
error C2664: 'fopen' : cannot convert parameter 1 from 'LPCTSTR' to 'const char *'
|
|
|
|
|
Use _tfopen() instead.
"Normal is getting dressed in clothes that you buy for work and driving through traffic in a car that you are still paying for, in order to get to the job you need to pay for the clothes and the car and the house you leave vacant all day so you can afford to live in it." - Ellen Goodman
"To have a respect for ourselves guides our morals; to have deference for others governs our manners." - Laurence Sterne
|
|
|
|
|
Hiya guys i seem to have this rather annoying problem, i'm trying to finish a 9 question assignment on C, however i have managed to finish 7 of those but am stuck on two of them. I tried finding hints/tips on the internet as well as try to understand the topic from library books but i still can't seem to understand the whole thing. Anyways i stumbled upon this site and i really need your help. If anyone can solve these two questions for me i would really appreciate it.
1- The day of the week for any given date can be calculated using Zeller's congruence, which can be neatly programmed into a computer. The technique is detailed below.
Assume that "year", "month" and "day" have been given as three integers, for example 1965, 8, 23 respectively for August 23rd 1965. The calculation continues.
if month < 3 then
month=month+12
year=year-1
end if
Then
nd=((13*month+3)\5+day+year+year\4-year\100+year\400)mod 7
The sign \ is used to indicate integer division (ignore the remainder) – to achieve the desired result simply use integers for everything (some languages, C not being one, actually have an ‘integer devision’ method). The "mod 7" terms means find the remainder after dividing by 7. Note: in C Mod is calculated in C using the ‘%’ , ie 16%8 is 16 mod 8 = 0
The result, nd, gives the day: 0 is Monday 1 is Tuesday etc. T
he formula is (of course!) year 2000 compliant, but only extends back to the Gregorian calendar revision, which occurred at different dates in different countries.
Ask the user to enter the day, month & year then, calculate ‘nd’ and then use this value in a switch statement where the ‘cases’ are enumerated variables defined for the days to display the relevant day of the week.
2- Unions:
You are required to create a union containing the various integer and float types and an array of unsigned chars.
The size of the array of chars should be the number of bytes used for storage of the largest variable type
Assign values to the various members of the union and then display the values of the bytes used for storage.
Extend the program from part 1 such that the bytes are displayed using a single function which is passed your union & the no of bytes for the type assigned.
Using your union from above ask the user to enter an integer value. Display the bytes used for storage.
Swap the bytes used in storage and then display the new byte sequence and the ‘new’ integer value. You should do this for ALL integer types > one byte in size.
Once again if anyone could help me with this i would really appreciate it, and i look forward to hearing from anyone soon. Thanx a lot.
Hayan
|
|
|
|
|
Answer to your first Question::
int day = 12, month = 1, year = 1984;<br />
<br />
if(month < 3)<br />
{<br />
month = month + 12;<br />
year = year - 1;<br />
}<br />
<br />
int nd = ((13 * month + 3) / 5 + day + year + year / 4 - year / 100 + year / 400) % 7;
now use nd as you want it will contain 0 to 6 for Monday, Tuesday,...,Sunday
Manish Patel.
B.E. - Information Technology.
|
|
|
|
|
I am not getting your second question.
Explain it again in brief
Manish Patel.
B.E. - Information Technology.
|
|
|
|
|
3alawii wrote: If anyone can solve these two questions for me i would really appreciate it.
So what are your questions?
3alawii wrote: if month < 3 then
month=month+12
year=year-1
end if
Hint: January and February are counted as month 13 and 14 of the previous year.
3alawii wrote: The sign \ is used to indicate integer division
Not in C/C++.
3alawii wrote: 2- Unions:
You are required to create a union containing the various integer and float types and an array of unsigned chars.
The size of the array of chars should be the number of bytes used for storage of the largest variable type
Assign values to the various members of the union and then display the values of the bytes used for storage.
See here.
"Normal is getting dressed in clothes that you buy for work and driving through traffic in a car that you are still paying for, in order to get to the job you need to pay for the clothes and the car and the house you leave vacant all day so you can afford to live in it." - Ellen Goodman
"To have a respect for ourselves guides our morals; to have deference for others governs our manners." - Laurence Sterne
|
|
|
|
|
This should get you on the way for your second question:
the union:
union AllTypes
{
signed short ssData;
unsigned short usData;
signed long slData;
unsigned long ulData;
float flData;
double dblData;
unsigned char ucData[8];
};
the display function:
void doPrint(unsigned char* pData, size_t tCount)
{
printf("data: ");
for(size_t tFoo = 0; tFoo < tCount; ++tFoo)
{
printf("%d ", pData[tFoo]);
}
printf("\n");
}
the Swap funtions:
void doShortSwap(unsigned short* pData)
{
unsigned short usTemp = 0xFF & *pData;
usTemp <<= 8;
*pData >>= 8;
*pData |= usTemp;
}
void doLongSwap(unsigned long* pData)
{
unsigned long ulTemp = 0xFFFF & *pData;
doShortSwap((unsigned short*)&ulTemp);
ulTemp <<= 16;
*pData >>= 16;
doShortSwap((unsigned short*)pData);
*pData |= ulTemp;
}
and an simple example:
<code>int main()
{
AllTypes var1;
var1.ulData = 12345687;
doPrint(var1.ucData, sizeof(AllTypes));
doLongSwap(&var1.ulData);
doPrint(var1.ucData, sizeof(AllTypes));
return 0;
}</code>
codito ergo sum
|
|
|
|
|
Hi Experts,
What it means by \\.\C:
I am using this to open a logical drive c: with CreateFile() API. What does mean by \\.\
|
|
|
|
|
a path starting by \\ is the UNC path to a computer. you can tell the PC's IP (like \\10.45.147.12), its UNC Name (like \\MyComputerName) or the syntax that Windows API understand too, which points to the current machine (i.e. \\.).
then, you point to a logical drive or share...
|
|
|
|
|
I understand what you say but... can you expand "UNC"? I don't know that acronyms
Greetings.
--------
M.D.V. 
If something has a solution... Why do we have to worry about?. If it has no solution... For what reason do we have to worry about?
Help me to understand what I'm saying, and I'll explain it better to you
“The First Rule of Program Optimization: Don't do it. The Second Rule of Program Optimization (for experts only!): Don't do it yet.” - Michael A. Jackson
|
|
|
|
|
|
You are right, I should have looked for. I thought it was something like IMO, ROFL or another english shortcut. Sorry
Greetings.
--------
M.D.V.
If something has a solution... Why do we have to worry about?. If it has no solution... For what reason do we have to worry about?
Help me to understand what I'm saying, and I'll explain it better to you
“The First Rule of Program Optimization: Don't do it. The Second Rule of Program Optimization (for experts only!): Don't do it yet.” - Michael A. Jackson
|
|
|
|
|
lol. 
|
|
|
|
|
Hi everybody,
Could you give me the answer which concern to inject code to other process.My questions are:
[1]Must Windows API function have the same address in all process?
[2]Why would crash when a remote thread proceduer directly call Windows API function?
Now I show my code:
<br />
DWORD __stdcall RemoteThreadProc(LPVOID lParam) <br />
{ <br />
LoadLibraryA(NULL);
return 0; <br />
}<br />
<br />
DWORD Inject(HANDLE hTargetProcess)<br />
{<br />
LoadLibraryA(NULL);
<br />
DWORD dwWriteBytes;<br />
DWORD dwThreadSize = 5000; <br />
<br />
void* pRemoteThread = VirtualAllocEx(hTargetProcess, 0, <br />
dwThreadSize, MEM_COMMIT | MEM_RESERVE, PAGE_EXECUTE_READWRITE);<br />
<br />
if (!WriteProcessMemory(hTargetProcess, pRemoteThread, <br />
RemoteThreadProc, dwThreadSize, 0)) {<br />
return 0;<br />
}<br />
<br />
HANDLE hRemoteThread = CreateRemoteThread(<br />
hTargetProcess, NULL, 0, (DWORD (__stdcall *)(void *))pRemoteThread,<br />
NULL, 0, &dwWriteBytes);<br />
<br />
if (!hRemoteThread) {<br />
return -1;<br />
}<br />
<br />
return 1;
}<br />
As far as known, Windows API function have same address in all process, but I can`t make sure it. For example, the address of "LoadLibraryA" is 0x7c801d77 in some process which I tested.[I get the address by printf(TEXT("%x"), LoadLibraryA ); ].
If Winsows API function have same address in all process, there are no reason to crash when the remote thread proceduer call API function .
Please give me an answer or an illumination.
Thank you.
|
|
|
|
|
Injecting functions written in high level programming language this way is unsafe, when they are relocated, some addresses change. It's safer to call
HANDLE hRemoteThread = CreateRemoteThread(<br />
hTargetProcess, NULL, 0, LoadLibraryA,<br />
pRemotelyAllocatedStringContainigPathToTheDll, 0, &dwWriteBytes);
And in the DllMain of this dll call your RemoteThreadProc.
Anyway, as far as I understand the comments in your code, WriteProcessMemory is the part that fails. What process do you try inject your code to?
Are you sure that you have sufficient rights?
-- added at 6:56 Wednesday 28th November, 2007
One more thing. Do you compile it in debug mode? If so, at the address of your function you'll see:
jmp some_other_address
Then WriteProcessMemory will copy just these 5 (6?) bytes and some "other" data, not useful for you instead of your function's body.
|
|
|
|
|
Dear maciu2020,
I know your method of injection. I just want to learn my code why to crash.In addition, I have step up the privilege of process`s handle before the to call the function 'Inject'.
In you code, LoadLibraryA is a parameter of CreateRemoteThread. Given the address of LoadLibraryA is 0x7c801d77, the following code is ok.
<br />
HANDLE hRemoteThread = CreateRemoteThread(<br />
hTargetProcess, NULL, 0, 0x7c801d77,<br />
pRemotelyAllocatedStringContainigPathToTheDll, 0, &dwWriteBytes);<br />
Why it`s ok ??? There is only one reason which the address of LoadLibraryA is same in all process! In other words, LoadLibraryA==0x7c801d77 in process A and LoadLibraryA==0x7c801d77 in process B at the same time. Do you agree with my opinion ???
This is the key of my question, which, in my code, local calling LoadLibraryA is jmp/call 0x7c801d77 and the calling LoadLibraryA in remote thread proceduer is also jmp/call 0x7c801d77. Why the latter must crash?
|
|
|
|
|
Actually the address may vary, windows sets it while loading kernel32.dll.
But on each machine, all processes share kernel32.dll functions' addresses.
DWORD __stdcall RemoteThreadProc(LPVOID lParam)<br />
{<br />
__asm<br />
{<br />
push 0<br />
call DWORD PTR LoadLibrary<br />
}<br />
}
should be ok...as long as you compile your program with optimizations on.
It would be definitely OK if you wrote the whole thing in assembly to ensure that compiler won't insert there something you don't want it to.
push 0<br />
call DWORD PTR LoadLibrary<br />
retn 0
generates the same code, no matter where it's placed.
If it still doesn't work, can you disassembly RemoteThreadProc and post here?
|
|
|
|
|
deng0jun wrote: LoadLibraryA(NULL); //crash!!! Why crash???
Why would you expect it not to crash?
"Normal is getting dressed in clothes that you buy for work and driving through traffic in a car that you are still paying for, in order to get to the job you need to pay for the clothes and the car and the house you leave vacant all day so you can afford to live in it." - Ellen Goodman
"To have a respect for ourselves guides our morals; to have deference for others governs our manners." - Laurence Sterne
|
|
|
|
|
I guess, because LoadLibraryA checks if it's argument is 0. And to indicate this, he wrote that the same LoadLbraryA(NULL), when placed in own process, just fails, doesn't crash.
|
|
|
|
|
DavidCrow wrote: Why would you expect it not to crash?
Because calling 'LoadLibraryA(NULL);' is ok in local process.
|
|
|
|
|
But what does it do?
"Normal is getting dressed in clothes that you buy for work and driving through traffic in a car that you are still paying for, in order to get to the job you need to pay for the clothes and the car and the house you leave vacant all day so you can afford to live in it." - Ellen Goodman
"To have a respect for ourselves guides our morals; to have deference for others governs our manners." - Laurence Sterne
|
|
|
|
|
Hello everybody.
I'm a MFC developer and I have a problem; i could not read a xml file in mfc (vs 6.0, c++). I don't know the differences reading a text file with reading a xml file, in mfc. Also; i don't know the xml open-read-write methods of the MFC (if there is??? ). How can I open and read xml files? Please help me.
Thanks in advance.
Sahan Askin
|
|
|
|
|
use tinyXML library in your project. it will ease your job
|
|
|
|
|
General 
News 
Suggestion 
Question 
Bug 
Answer 
Joke 
Praise 
Rant 
Admin 
Submit an article or tip
