From C++ standard:
Attempting to read or modify the stored value through any other type results in undefined behavior.
The first basic example illustrating this principle:
#include <cstdint>
std::uint32_t toInt(float value)
{
auto* p = reinterpret_cast<std::uint32_t*>(&value); // The cast itself is permitted.
return *p; // Undefined behavior: accesses a float object through a std::uint32_t glvalue.
}
The first simple example:
#include <bit>
#include <cstdint>
#include <iomanip>
#include <iostream>
std::uint32_t badBits(const float value)
{
// const prevents writes, but reading a float through a uint32_t pointer
// still violates the strict-aliasing rule.
const auto* bits = reinterpret_cast<const std::uint32_t*>(&value);
return *bits; // Undefined behavior.
}
std::uint32_t goodBits(const float value)
{
// std::bit_cast copies the object representation without violating
// strict-aliasing or object-lifetime rules.
return std::bit_cast<std::uint32_t>(value);
}
int main()
{
constexpr float value = 1.0F;
std::cout << std::hex
<< "bad: 0x" << badBits(value) << '\n'
<< "good: 0x" << goodBits(value) << '\n';
}
Get-ChildItem `
'HKCU:\Software\Microsoft\Terminal Server Client\Servers' |
ForEach-Object {
$p = Get-ItemProperty $_.PSPath
[PSCustomObject]@{
Server = $_.PSChildName
Username = $p.UsernameHint
}
}
The code below does not compile in C++:
template <class Result, class... Params>
class Slot
{
public:
virtual Result operator()(Params ... args) = 0;
};
I registered a sample Credential Provider with the following .reg file:
Windows Registry Editor Version 5.00
[HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\Windows\CurrentVersion\Authentication\Credential Providers\{5fd3d285-0dd9-4362-8855-e0abaacd4af6}]
@="SampleV2CredentialProvider"
[HKEY_CLASSES_ROOT\CLSID\{5fd3d285-0dd9-4362-8855-e0abaacd4af6}]
@="SampleV2CredentialProvider"
[HKEY_CLASSES_ROOT\CLSID\{5fd3d285-0dd9-4362-8855-e0abaacd4af6}\InprocServer32]
@="SampleV2CredentialProvider.dll"
"ThreadingModel"="Apartment"
On DC with IP address 192.168.0.123:
wevtutil sl Microsoft-Windows-NTLM/Operational /e:true
wevtutil qe Microsoft-Windows-NTLM/Operational /q:"*[System[(EventID=8004 or EventID=8005)]]" /f:text
net share
Share name Resource Remark
-------------------------------------------------------------------------------
C$ C:\ Default share
IPC$ Remote IPC
ADMIN$ C:\Windows Remote Admin
NETLOGON C:\Windows\SYSVOL\sysvol\my.local\SCRIPTS
Logon server share
SYSVOL C:\Windows\SYSVOL\sysvol Logon server share
The command completed successfully.
I realized that my LDAPS certificate is not trusted with the following command in PowerShell:
certutil -verify ldap.crt
A coroutine func accepts a parameter by const reference in the code below:
#include <boost/asio.hpp>
#include <iostream>
namespace asio = boost::asio;
using asio::awaitable;
using asio::use_awaitable;
class Param
{
public:
Param(int val) : m_val(val)
{
std::cout << "Param constructor " << m_val << std::endl;
}
