class CComMultiThreadModelNoCS
CComMultiThreadModelNoCS is similar to CComMultiThreadModel in that it provides thread-safe methods for incrementing and decrementing a variable. However, when you reference a critical section class through CComMultiThreadModelNoCS, methods such as Lock and Unlock will do nothing.
Typically, you use CComMultiThreadModelNoCS through the ThreadModelNoCS typedef name. This typedef is defined in CComMultiThreadModelNoCS, CComMultiThreadModel, and CComSingleThreadModel.
Note The global typedef names CComObjectThreadModel and CComGlobalsThreadModel do not reference CComMultiThreadModelNoCS.
In addition to ThreadModelNoCS, CComMultiThreadModelNoCS defines AutoCriticalSection and CriticalSection. These latter two typedef names reference CComFakeCriticalSection, which provides empty methods associated with obtaining and releasing a critical section.
#include <atlbase.h>
Methods | |
Decrement | Decrements the value of the specified variable in a thread-safe manner. |
Increment | Increments the value of the specified variable in a thread-safe manner. |
Typedefs | |
AutoCriticalSection | References class CComFakeCriticalSection. |
CriticalSection | References class CComFakeCriticalSection. |
ThreadModelNoCS | References class CComMultiThreadModelNoCS. |
CComMultiThreadModelNoCS Overview
static ULONG Decrement( LPLONG p );
Return Value
If the result of the decrement is 0, then Decrement returns 0. If the result of the decrement is nonzero, the return value is also nonzero but may not equal the result of the decrement.
Parameters
p [in] Pointer to the variable to be decremented.
Remarks
This static method calls the Win32 function InterlockedDecrement, which decrements the value of the variable pointed to by p. InterlockedDecrement prevents more than one thread from simultaneously using this variable.
CComMultiThreadModelNoCS Overview | Class Members
See Also CComMultiThreadModelNoCS::Increment, InterlockedDecrement in the Win32 SDK
static ULONG Increment( LPLONG p );
Return Value
If the result of the increment is 0, then Increment returns 0. If the result of the increment is nonzero, the return value is also nonzero but may not equal the result of the increment.
Parameters
p [in] Pointer to the variable to be incremented.
Remarks
This static method calls the Win32 function InterlockedIncrement, which increments the value of the variable pointed to by p. InterlockedIncrement prevents more than one thread from simultaneously using this variable.
CComMultiThreadModelNoCS Overview | Class Members
See Also CComMultiThreadModelNoCS::Decrement, InterlockedIncrement in the Win32 SDK
typedef CComFakeCriticalSection AutoCriticalSection;
Remarks
When using CComMultiThreadModelNoCS, the typedef name AutoCriticalSection references class CComFakeCriticalSection. Because CComFakeCriticalSection does not provide a critical section, its methods do nothing.
CComMultiThreadModel and CComSingleThreadModel also contain definitions for AutoCriticalSection. The following table shows the relationship between the threading model class and the critical section class referenced by AutoCriticalSection:
Class defined in | Class referenced |
CComMultiThreadModelNoCS | CComFakeCriticalSection |
CComMultiThreadModel | CComAutoCriticalSection |
CComSingleThreadModel | CComFakeCriticalSection |
In addition to AutoCriticalSection, you can use the typedef name CriticalSection. You should not specify AutoCriticalSection in global objects or static class members if you want to eliminate the CRT startup code.
Example
See CComMultiThreadModel::AutoCriticalSection.
CComMultiThreadModelNoCS Overview | Class Members
See Also CComObjectThreadModel, CComGlobalsThreadModel, CComMultiThreadModelNoCS::ThreadModelNoCS
typedef CComFakeCriticalSection CriticalSection;
Remarks
When using CComMultiThreadModelNoCS, the typedef name CriticalSection references class CComFakeCriticalSection. Because CComFakeCriticalSection does not provide a critical section, its methods do nothing.
CComMultiThreadModel and CComSingleThreadModel also contain definitions for CriticalSection. The following table shows the relationship between the threading model class and the critical section class referenced by CriticalSection:
Class defined in | Class referenced |
CComMultiThreadModelNoCS | CComFakeCriticalSection |
CComMultiThreadModel | CComCriticalSection |
CComSingleThreadModel | CComFakeCriticalSection |
In addition to CriticalSection, you can use the typedef name AutoCriticalSection. You should not specify AutoCriticalSection in global objects or static class members if you want to eliminate the CRT startup code.
Example
See CComMultiThreadModel::AutoCriticalSection.
CComMultiThreadModelNoCS Overview | Class Members
See Also CComObjectThreadModel, CComGlobalsThreadModel, CComMultiThreadModelNoCS::ThreadModelNoCS
typedef CComMultiThreadModelNoCS ThreadModelNoCS;
Remarks
When using CComMultiThreadModelNoCS, the typedef name ThreadModelNoCS simply references CComMultiThreadModelNoCS.
CComMultiThreadModel and CComSingleThreadModel also contain definitions for ThreadModelNoCS. The following table shows the relationship between the threading model class and the class referenced by ThreadModelNoCS:
Class defined in | Class referenced |
CComMultiThreadModelNoCS | CComMultiThreadModelNoCS |
CComMultiThreadModel | CComMultiThreadModelNoCS |
CComSingleThreadModel | CComSingleThreadModel |
Example
See CComMultiThreadModel::AutoCriticalSection.
Note that the definition of ThreadModelNoCS in CComMultiThreadModelNoCS provides symmetry with CComMultiThreadModel and CComSingleThreadModel. For example, suppose the sample code in CComMultiThreadModel::AutoCriticalSection declared the following typedef:
typedef ThreadModel::ThreadModelNoCS _ThreadModel;
Regardless of the class specified for ThreadModel (such as CComMultiThreadModelNoCS), _ThreadModel resolves accordingly.
CComMultiThreadModelNoCS Overview | Class Members
See Also CComObjectThreadModel, CComGlobalsThreadModel