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I have a client system, to create a CMainFrame object, but I am afraid that there will be memory leak about CMainFrame object.After step in, I cannot find where the m_pMainWnd pointer is deleted. Will I delete this pointer in the function
ExitInstance()? 
BOOL CApp::InitInstance()
{
CMainFrame* pMainFrame = new CMainFrame();
if (!pMainFrame) return FALSE;
pMainFrame->LoadFrame(IDR_MAINFRAME,
WS_OVERLAPPEDWINDOW | FWS_ADDTOTITLE, NULL,
NULL);
m_pMainWnd = pMainFrame;
m_pMainWnd->UpdateWindow();
return TRUE;
}
int CApp::ExitInstance()
{
return CWinApp::ExitInstance();
}
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yu-jian wrote: After step in, I cannot find where the m_pMainWnd pointer is deleted.
It's handled automatically by the framework.
"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
"Show me a community that obeys the Ten Commandments and I'll show you a less crowded prison system." - Anonymous
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Oh, sorry, I do not use the .net.
This is the unmanaged C++. I cannot see where the system delete this pointer in file appcore.cpp. 
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yu-jian wrote: Oh, sorry, I do not use the .net.
What does that have to do with anything?
yu-jian wrote: This is the unmanaged C++.
If you mean this is the unmanaged C++ forum, of course it is. Did something indicate otherwise?
"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
"Show me a community that obeys the Ten Commandments and I'll show you a less crowded prison system." - Anonymous
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It is is deleted inside CFrameWnd::PostNcDestroy() (see winfrm.cpp) which is called by CWnd::OnNcDestroy which is the last member function called when the Windows window is destroyed.
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Hello everyone,
I am trying to implement zero copy mechanism i.e. a contrary function to the TransmitFile() API.
But I don't know how to register buffers in kernel.Below are the details what I want to do to implement zero copy:
1.we will receive a large data from the server in our client buffer, i have a doubt here also that weather data will come to socket buffer(client's) or first it will come into NIC buffer,please clear this doubt also.
2.now from socket buufer i want to copy the data directly to the kernel buffer and then to file in the disc without going for read and write system calls i.e without switching contexts.
3.Data has to be moved directly to kernel buffer within kernel space only.
Is there any API or some method???? any suggestions???
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So you want to take data direct over a network and write it to disk without going through huser mode.
Why, are you that concerned about performance? If you do it in massive chunks you wont be that badly affected.
If you really want to write a minifilter driver that can intercept the data intended for your socket and and have it do a ZwWriteFile then you are going to have to learn an awful lot of kernel stuff.
Of course I could do it in a day or so, since I know an awful lot of kernel stuff, but I wont tell you because it will take you about a year to get working and will cost you a lot of time and money.
Of course if you want it doing properly and relatively cheaply hire someone who knows.
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sorry buddy....thankx for the hint(ZwWritefile).as I am a beginner its a little tough task to understand and implement it.I hope I got the hint correct,I mean i need to study zwwritefile?isn't it?
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No no no no no. DOnt go near zwwritefile or the kernel, it will be impossible. Just take the data into user space in large chunks and write it to file from userspace in large chunks.
The cost of a few user-kernel transitions will not impact your performance unless you have a really really fast network and are moving huge amounts of data. If you really have to do it in the kernel then call in an expert.
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hi everyone.. I have written a program where I want to return three user defined data types to the another main() function (here i have not mentioned that main). I want to return {Pa,c1,c2} from this program. Please help me out.
#include <cstdlib>
#include <iostream>
#include <vector>
using std:: cout;
using std:: cin;
using std:: endl;
using namespace std;
#include <math.h>
#include "FiniteFieldElement.hpp"
namespace Cryptography
{
template<int P>
class EllipticCurve
{
public:
typedef FiniteFieldElement<P> ffe_t;
class Point
{
friend class EllipticCurve<P>;
typedef FiniteFieldElement<P> ffe_t;
ffe_t x_;
ffe_t y_;
EllipticCurve *ec_;
void addDouble(int m, Point& acc)
{
if ( m > 0 )
{
Point r = acc;
for ( int n=0; n < m; ++n )
{
r += r;
}
acc = r;
}
}
Point scalarMultiply(int k, const Point& a)
{
Point acc = a;
Point res = Point(0,0,*ec_);
int i = 0, j = 0;
int b = k;
while( b )
{
if ( b & 1 )
{
addDouble(i-j,acc);
res += acc;
j = i;
}
b >>= 1;
++i;
}
return res;
}
void add(ffe_t x1, ffe_t y1, ffe_t x2, ffe_t y2, ffe_t & xR, ffe_t & yR) const
{
if ( x1 == 0 && y1 == 0 )
{
xR = x2;
yR = y2;
return;
}
if ( x2 == 0 && y2 == 0 )
{
xR = x1;
yR = y1;
return;
}
if ( y1 == -y2 )
{
xR = yR = 0;
return;
}
ffe_t s;
if ( x1 == x2 && y1 == y2 )
{
s = (3*(x1.i()*x1.i()) + ec_->a()) / (2*y1);
xR = ((s*s) - 2*x1);
}
else
{
s = (y1 - y2) / (x1 - x2);
xR = ((s*s) - x1 - x2);
}
if ( s != 0 )
{
yR = (-y1 + s*(x1 - xR));
}
else
{
xR = yR = 0;
}
}
Point(int x, int y)
: x_(x),
y_(y),
ec_(0)
{}
Point(int x, int y, EllipticCurve<P> & EllipticCurve)
: x_(x),
y_(y),
ec_(&EllipticCurve)
{}
Point(const ffe_t& x, const ffe_t& y, EllipticCurve<P> & EllipticCurve)
: x_(x),
y_(y),
ec_(&EllipticCurve)
{}
public:
static Point ONE;
Point(const Point& rhs)
{
x_ = rhs.x_;
y_ = rhs.y_;
ec_ = rhs.ec_;
}
Point& operator=(const Point& rhs)
{
x_ = rhs.x_;
y_ = rhs.y_;
ec_ = rhs.ec_;
return *this;
}
ffe_t x() const { return x_; }
ffe_t y() const { return y_; }
unsigned int Order(unsigned int maxPeriod = ~0) const
{
Point r = *this;
unsigned int n = 0;
while( r.x_ != 0 && r.y_ != 0 )
{
++n;
r += *this;
if ( n > maxPeriod ) break;
}
return n;
}
Point operator-()
{
return Point(x_,-y_);
}
friend bool operator==(const Point& lhs, const Point& rhs)
{
return (lhs.ec_ == rhs.ec_) && (lhs.x_ == rhs.x_) && (lhs.y_ == rhs.y_);
}
friend bool operator!=(const Point& lhs, const Point& rhs)
{
return (lhs.ec_ != rhs.ec_) || (lhs.x_ != rhs.x_) || (lhs.y_ != rhs.y_);
}
friend Point operator+(const Point& lhs, const Point& rhs)
{
ffe_t xR, yR;
lhs.add(lhs.x_,lhs.y_,rhs.x_,rhs.y_,xR,yR);
return Point(xR,yR,*lhs.ec_);
}
friend Point operator*(int k, const Point& rhs)
{
return Point(rhs).operator*=(k);
}
Point& operator+=(const Point& rhs)
{
add(x_,y_,rhs.x_,rhs.y_,x_,y_);
return *this;
}
Point& operator*=(int k)
{
return (*this = scalarMultiply(k,*this));
}
friend ostream& operator <<(ostream& os, const Point& p)
{
return (os << "(" << p.x_ << ", " << p.y_ << ")");
}
};
typedef EllipticCurve<P> this_t;
typedef class EllipticCurve<P>::Point point_t;
EllipticCurve(int a, int b)
: a_(a),
b_(b),
m_table_(),
table_filled_(false)
{
}
void CalculatePoints()
{
int x_val[P];
int y_val[P];
for ( int n = 0; n < P; ++n )
{
int nsq = n*n;
x_val[n] = ((n*nsq) + a_.i() * n + b_.i()) % P;
y_val[n] = nsq % P;
}
for ( int n = 0; n < P; ++n )
{
for ( int m = 0; m < P; ++m )
{
if ( x_val[n] == y_val[m] )
{
m_table_.push_back(Point(n,m,*this));
}
}
}
table_filled_ = true;
}
Point operator[](int n)
{
if ( !table_filled_ )
{
CalculatePoints();
}
return m_table_[n];
}
size_t Size() const { return m_table_.size(); }
int Degree() const { return P; }
FiniteFieldElement<P> a() const { return a_; }
FiniteFieldElement<P> b() const { return b_; }
template<int T>
friend ostream& operator <<(ostream& os, const EllipticCurve<T>& EllipticCurve);
ostream& PrintTable(ostream &os, int columns=4);
private:
typedef std::vector<Point> m_table_t;
m_table_t m_table_;
FiniteFieldElement<P> a_;
FiniteFieldElement<P> b_;
bool table_filled_;
};
template<int T>
typename EllipticCurve<T>::Point EllipticCurve<T>::Point::ONE(0,0);
template<int T>
ostream& operator <<(ostream& os, const EllipticCurve<T>& EllipticCurve)
{
os << "y^2 mod " << T << " = (x^3" << showpos;
if ( EllipticCurve.a_ != 0 )
{
os << EllipticCurve.a_ << "x";
}
if ( EllipticCurve.b_.i() != 0 )
{
os << EllipticCurve.b_;
}
os << noshowpos << ") mod " << T;
return os;
}
template<int P>
ostream& EllipticCurve<P>::PrintTable(ostream &os, int columns)
{
if ( table_filled_ )
{
int col = 0;
typename EllipticCurve<P>::m_table_t::iterator iter = m_table_.begin();
for ( ; iter!=m_table_.end(); ++iter )
{
os << "(" << (*iter).x_.i() << ", " << (*iter).y_.i() << ") ";
if ( ++col > columns )
{
os << "\n";
col = 0;
}
}
}
else
{
os << "EllipticCurve, F_" << P;
}
return os;
}
}
namespace utils
{
float frand()
{
static float norm = 1.0f / (float)RAND_MAX;
return (float)rand()*norm;
}
int irand(int min, int max)
{
return min+(int)(frand()*(float)(max-min));
}
}
using namespace Cryptography;
using namespace utils;
int main(int argc, char *argv[])
{
typedef EllipticCurve<263> ec_t;
ec_t myEllipticCurve(1,1);
cout << "A little Elliptic Curve cryptography example\nby Jarl Ostensen, 2007\n\n";
cout << "The elliptic curve: " << myEllipticCurve << "\n";
myEllipticCurve.CalculatePoints();
cout << "\nPoints on the curve (i.e. the group elements):\n";
myEllipticCurve.PrintTable(cout,5);
cout << "\n\n";
ec_t::Point P = myEllipticCurve[2];
cout << "some point P = " << P << ", 2P = " << (P+P) << "\n";
ec_t::Point Q = myEllipticCurve[3];
cout << "some point Q = " << Q << ", P+Q = " << (P+Q) << "\n";
ec_t::Point R = P;
R += Q;
cout << "P += Q = " << R << "\n";
R = P;
R += R;
cout << "P += P = 2P = " << R << "\n";
cout << "\nEC message encryption example\n===============================================\n\n";
ec_t::Point G = myEllipticCurve[0];
while( (G.y() == 0 || G.x() == 0) || (G.Order()<2) )
{
int n = (int)(frand()*myEllipticCurve.Size());
G = myEllipticCurve[n];
}
cout << "G = " << G << ", order(G) is " << G.Order() << "\n";
int a = irand(1,myEllipticCurve.Degree()-1);
ec_t::Point Pa = a*G;
cout << "Alice' public key Pa = " << a << "*" << G << " = " << Pa << endl;
int b = irand(1,myEllipticCurve.Degree()-1);;
ec_t::Point Pb = b*G;
cout << "Bob's public key Pb = " << b << "*" << G << " = " << Pb << endl;
int j = irand(1,myEllipticCurve.Degree()-1);;
ec_t::Point Pj = j*G;
cout << "Jane's public key Pj = " << j << "*" << G << " = " << Pj << endl;
cout << "\n\n";
int m1,m2;
cout << "Enter two message\n"<< endl;
cin >> m1;
cin >> m2;
cout << "Plain text message from Alice to Bob: (" << m1 << ", " << m2 << ")\n";
ec_t::Point Pk = a*Pb;
ec_t::ffe_t c1( m1*Pk.x() );
ec_t::ffe_t c2( m2*Pk.y() );
cout << "Encrypted message from Alice to Bob = {Pa,c1,c2} = {" << Pa << ", " << c1 << ", " << c2 << "}\n\n";
Pk = b*Pa;
ec_t::ffe_t m1d = c1/Pk.x();
ec_t::ffe_t m2d = c2/Pk.y();
cout << "\tBob's decrypted message from Alice = (" << m1d << ", " << m2d << ")" << endl;
Pk = j*Pa;
m1d = c1/Pk.x();
m2d = c2/Pk.y();
cout << "\nJane's decrypted message from Alice = (" << m1d << ", " << m2d << ")" << endl;
cout << endl;
}
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hi everyone.. I have written a program where I want to return three user defined data types to the another main() function (here i have not mentioned that main). I want to return {Pa,c1,c2} from this program. Please help me out.
#include <cstdlib>
#include <iostream>
#include <vector>
using std:: cout;
using std:: cin;
using std:: endl;
using namespace std;
#include <math.h>
#include "FiniteFieldElement.hpp"
namespace Cryptography
{
template<int P>
class EllipticCurve
{
public:
typedef FiniteFieldElement<P> ffe_t;
class Point
{
friend class EllipticCurve<P>;
typedef FiniteFieldElement<P> ffe_t;
ffe_t x_;
ffe_t y_;
EllipticCurve *ec_;
void addDouble(int m, Point& acc)
{
if ( m > 0 )
{
Point r = acc;
for ( int n=0; n < m; ++n )
{
r += r;
}
acc = r;
}
}
Point scalarMultiply(int k, const Point& a)
{
Point acc = a;
Point res = Point(0,0,*ec_);
int i = 0, j = 0;
int b = k;
while( b )
{
if ( b & 1 )
{
addDouble(i-j,acc);
res += acc;
j = i;
}
b >>= 1;
++i;
}
return res;
}
void add(ffe_t x1, ffe_t y1, ffe_t x2, ffe_t y2, ffe_t & xR, ffe_t & yR) const
{
if ( x1 == 0 && y1 == 0 )
{
xR = x2;
yR = y2;
return;
}
if ( x2 == 0 && y2 == 0 )
{
xR = x1;
yR = y1;
return;
}
if ( y1 == -y2 )
{
xR = yR = 0;
return;
}
ffe_t s;
if ( x1 == x2 && y1 == y2 )
{
s = (3*(x1.i()*x1.i()) + ec_->a()) / (2*y1);
xR = ((s*s) - 2*x1);
}
else
{
s = (y1 - y2) / (x1 - x2);
xR = ((s*s) - x1 - x2);
}
if ( s != 0 )
{
yR = (-y1 + s*(x1 - xR));
}
else
{
xR = yR = 0;
}
}
Point(int x, int y)
: x_(x),
y_(y),
ec_(0)
{}
Point(int x, int y, EllipticCurve<P> & EllipticCurve)
: x_(x),
y_(y),
ec_(&EllipticCurve)
{}
Point(const ffe_t& x, const ffe_t& y, EllipticCurve<P> & EllipticCurve)
: x_(x),
y_(y),
ec_(&EllipticCurve)
{}
public:
static Point ONE;
Point(const Point& rhs)
{
x_ = rhs.x_;
y_ = rhs.y_;
ec_ = rhs.ec_;
}
Point& operator=(const Point& rhs)
{
x_ = rhs.x_;
y_ = rhs.y_;
ec_ = rhs.ec_;
return *this;
}
ffe_t x() const { return x_; }
ffe_t y() const { return y_; }
unsigned int Order(unsigned int maxPeriod = ~0) const
{
Point r = *this;
unsigned int n = 0;
while( r.x_ != 0 && r.y_ != 0 )
{
++n;
r += *this;
if ( n > maxPeriod ) break;
}
return n;
}
Point operator-()
{
return Point(x_,-y_);
}
friend bool operator==(const Point& lhs, const Point& rhs)
{
return (lhs.ec_ == rhs.ec_) && (lhs.x_ == rhs.x_) && (lhs.y_ == rhs.y_);
}
friend bool operator!=(const Point& lhs, const Point& rhs)
{
return (lhs.ec_ != rhs.ec_) || (lhs.x_ != rhs.x_) || (lhs.y_ != rhs.y_);
}
friend Point operator+(const Point& lhs, const Point& rhs)
{
ffe_t xR, yR;
lhs.add(lhs.x_,lhs.y_,rhs.x_,rhs.y_,xR,yR);
return Point(xR,yR,*lhs.ec_);
}
friend Point operator*(int k, const Point& rhs)
{
return Point(rhs).operator*=(k);
}
Point& operator+=(const Point& rhs)
{
add(x_,y_,rhs.x_,rhs.y_,x_,y_);
return *this;
}
Point& operator*=(int k)
{
return (*this = scalarMultiply(k,*this));
}
friend ostream& operator <<(ostream& os, const Point& p)
{
return (os << "(" << p.x_ << ", " << p.y_ << ")");
}
};
typedef EllipticCurve<P> this_t;
typedef class EllipticCurve<P>::Point point_t;
EllipticCurve(int a, int b)
: a_(a),
b_(b),
m_table_(),
table_filled_(false)
{
}
void CalculatePoints()
{
int x_val[P];
int y_val[P];
for ( int n = 0; n < P; ++n )
{
int nsq = n*n;
x_val[n] = ((n*nsq) + a_.i() * n + b_.i()) % P;
y_val[n] = nsq % P;
}
for ( int n = 0; n < P; ++n )
{
for ( int m = 0; m < P; ++m )
{
if ( x_val[n] == y_val[m] )
{
m_table_.push_back(Point(n,m,*this));
}
}
}
table_filled_ = true;
}
Point operator[](int n)
{
if ( !table_filled_ )
{
CalculatePoints();
}
return m_table_[n];
}
size_t Size() const { return m_table_.size(); }
int Degree() const { return P; }
FiniteFieldElement<P> a() const { return a_; }
FiniteFieldElement<P> b() const { return b_; }
template<int T>
friend ostream& operator <<(ostream& os, const EllipticCurve<T>& EllipticCurve);
ostream& PrintTable(ostream &os, int columns=4);
private:
typedef std::vector<Point> m_table_t;
m_table_t m_table_;
FiniteFieldElement<P> a_;
FiniteFieldElement<P> b_;
bool table_filled_;
};
template<int T>
typename EllipticCurve<T>::Point EllipticCurve<T>::Point::ONE(0,0);
template<int T>
ostream& operator <<(ostream& os, const EllipticCurve<T>& EllipticCurve)
{
os << "y^2 mod " << T << " = (x^3" << showpos;
if ( EllipticCurve.a_ != 0 )
{
os << EllipticCurve.a_ << "x";
}
if ( EllipticCurve.b_.i() != 0 )
{
os << EllipticCurve.b_;
}
os << noshowpos << ") mod " << T;
return os;
}
template<int P>
ostream& EllipticCurve<P>::PrintTable(ostream &os, int columns)
{
if ( table_filled_ )
{
int col = 0;
typename EllipticCurve<P>::m_table_t::iterator iter = m_table_.begin();
for ( ; iter!=m_table_.end(); ++iter )
{
os << "(" << (*iter).x_.i() << ", " << (*iter).y_.i() << ") ";
if ( ++col > columns )
{
os << "\n";
col = 0;
}
}
}
else
{
os << "EllipticCurve, F_" << P;
}
return os;
}
}
namespace utils
{
float frand()
{
static float norm = 1.0f / (float)RAND_MAX;
return (float)rand()*norm;
}
int irand(int min, int max)
{
return min+(int)(frand()*(float)(max-min));
}
}
using namespace Cryptography;
using namespace utils;
int main(int argc, char *argv[])
{
typedef EllipticCurve<263> ec_t;
ec_t myEllipticCurve(1,1);
cout << "A little Elliptic Curve cryptography example\nby Jarl Ostensen, 2007\n\n";
cout << "The elliptic curve: " << myEllipticCurve << "\n";
myEllipticCurve.CalculatePoints();
cout << "\nPoints on the curve (i.e. the group elements):\n";
myEllipticCurve.PrintTable(cout,5);
cout << "\n\n";
ec_t::Point P = myEllipticCurve[2];
cout << "some point P = " << P << ", 2P = " << (P+P) << "\n";
ec_t::Point Q = myEllipticCurve[3];
cout << "some point Q = " << Q << ", P+Q = " << (P+Q) << "\n";
ec_t::Point R = P;
R += Q;
cout << "P += Q = " << R << "\n";
R = P;
R += R;
cout << "P += P = 2P = " << R << "\n";
cout << "\nEC message encryption example\n===============================================\n\n";
ec_t::Point G = myEllipticCurve[0];
while( (G.y() == 0 || G.x() == 0) || (G.Order()<2) )
{
int n = (int)(frand()*myEllipticCurve.Size());
G = myEllipticCurve[n];
}
cout << "G = " << G << ", order(G) is " << G.Order() << "\n";
int a = irand(1,myEllipticCurve.Degree()-1);
ec_t::Point Pa = a*G;
cout << "Alice' public key Pa = " << a << "*" << G << " = " << Pa << endl;
int b = irand(1,myEllipticCurve.Degree()-1);;
ec_t::Point Pb = b*G;
cout << "Bob's public key Pb = " << b << "*" << G << " = " << Pb << endl;
int j = irand(1,myEllipticCurve.Degree()-1);;
ec_t::Point Pj = j*G;
cout << "Jane's public key Pj = " << j << "*" << G << " = " << Pj << endl;
cout << "\n\n";
int m1,m2;
cout << "Enter two message\n"<< endl;
cin >> m1;
cin >> m2;
cout << "Plain text message from Alice to Bob: (" << m1 << ", " << m2 << ")\n";
ec_t::Point Pk = a*Pb;
ec_t::ffe_t c1( m1*Pk.x() );
ec_t::ffe_t c2( m2*Pk.y() );
cout << "Encrypted message from Alice to Bob = {Pa,c1,c2} = {" << Pa << ", " << c1 << ", " << c2 << "}\n\n";
Pk = b*Pa;
ec_t::ffe_t m1d = c1/Pk.x();
ec_t::ffe_t m2d = c2/Pk.y();
cout << "\tBob's decrypted message from Alice = (" << m1d << ", " << m2d << ")" << endl;
Pk = j*Pa;
m1d = c1/Pk.x();
m2d = c2/Pk.y();
cout << "\nJane's decrypted message from Alice = (" << m1d << ", " << m2d << ")" << endl;
cout << endl;
}
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Return it to where, and where and what are these variables?
Please also delete your duplicate of this post.
Use the best guess
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Both threads are copies from here
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How to get the process's DLL module address?
And How to get process imagebase?
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It's not clear exactly what your problem is but you may want to start with GetModuleHandleEx()[^].
Use the best guess
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Enumerating all modules in a process can be done by EnumProcessModules().
Here is an example of enumerating all modules in a process and displaying its names.
http://msdn.microsoft.com/en-us/library/windows/desktop/ms682621(v=vs.85).aspx
Load address of each modules can be retrieved by calling GetModuleInformation() for each modules.
lpBaseOfDll of MODULEINFO holds the load address of the corresponding module.
BOOL WINAPI GetModuleInformation(
__in HANDLE hProcess,
__in HMODULE hModule,
__out LPMODULEINFO lpmodinfo,
__in DWORD cb
);
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HMODULE hMod = LoadLibrary("mydll.dll");
if (hMod) {
void (*)() myfn = (void (*)())GetProcAddress(hMod, "myfn");
if (myfn) myfn();
FreeLibrary(hMod);
}
EDIT:
Wasn't exactly sure what you're asking...
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I have a list view with ownerdata and custom draw. when i do listview_update it updates the list but what If I want to update a specific column instead of all cols?
-----------------------
| col1 | col2 | col3 |
-----------------------
just col1 i is that possible?
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Why not update the data that is used to populate the list? Then when the list is refreshed, the new values will be shown.
"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
"Show me a community that obeys the Ten Commandments and I'll show you a less crowded prison system." - Anonymous
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I have decided to simplify my database using plain text files.
So this is my first usage of MFC CFile and I am wondering why CFile → Read reads only up to the first comma it finds in the text file irregardless how many bytes it suppose to read.
Is that by design or did I missed something?
Thanks for you help.
Cheers
Vaclav
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I am pretty sure you are doing something wrong, perhaps you can share some of your code with us. CFile is for generic, binary file handling and does not care which characters you read and write.
You might consider using CStdioFile instead - it operates on files in text mode and provides a ReadString()[^] method, which makes it simple to read a text file line-by-line.
Soren Madsen
"When you don't know what you're doing it's best to do it quickly" - Jase #DuckDynasty
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Soren, thanks for your help.
Here is the read code.
I did add \n after the comma to the write text.
The file as around 230 bytes, ten string entries (sample "WS2EEE,\n") and even with the iReadBytes set to 250 it get only the first string with comma attached.
I am also having some problems with using Seek to next "record", but I can work on that later.
I was hoping to read the entire file and than process it , but I'll try the CStdioFile and read one line instead.
char pbuf[1000];
UINT nBytesRead;
UINT iRunningTotal = 0;
CString strField, strExcluded;
int iReadBytes = 250;
do
{
nBytesRead = pFile->Read( pbuf, iReadBytes );
TRACE("\nBuffer %s", pbuf);
// extract to delimiting comma
strField = pbuf; // kluge need to learn how to use CString buffer
strExcluded = strField .SpanExcluding( ";,.- :");
int iLenght = strExcluded.GetLength();
iReadBytes = iLenght + 2;
pFile->Seek(iLenght +1 ,CFile::current);
iRunningTotal += nBytesRead;
}while ( iRunningTotal < dwFileLength);
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Change your loop to:
CString strLine;
while (file.ReadString(strLine))
{
}
"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
"Show me a community that obeys the Ten Commandments and I'll show you a less crowded prison system." - Anonymous
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Sorry for the delay Vaclav, it has been one of those days.
I think you should do this with CStdioFile and get the text parsing all straightened out first. Follow David's advice for the read loop.
If you still want to do some testing with your current code, you need to clean up some things. You say you hope to read the whole file in and then process it. Well, then that is what you should do instead of doing both reading and processing in the loop.
I will recommend you use a CByteArray for the read buffer (I like its flexibility). Use CFile to check the size of the file, call SetSize() on the CByteArray object with that value, read the file in a single call (for now let's just assume your files will not be too large for that) and close the file. Then you use the loop to go through the buffer without doing anymore file handling.
Soren Madsen
"When you don't know what you're doing it's best to do it quickly" - Jase #DuckDynasty
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