SemaphoreAccessRule Class

 

Represents a set of access rights allowed or denied for a user or group. This class cannot be inherited.

Namespace:   System.Security.AccessControl
Assembly:  System (in System.dll)

System.Object
  System.Security.AccessControl.AuthorizationRule
    System.Security.AccessControl.AccessRule
      System.Security.AccessControl.SemaphoreAccessRule

[<Sealed>]
[<ComVisibleAttribute(false)>]
type SemaphoreAccessRule = 
    class
        inherit AccessRule
    end

NameDescription
System_CAPS_pubmethodSemaphoreAccessRule(IdentityReference, SemaphoreRights, AccessControlType)

Initializes a new instance of the SemaphoreAccessRule class, specifying the user or group the rule applies to, the access rights, and whether the specified access rights are allowed or denied.

System_CAPS_pubmethodSemaphoreAccessRule(String, SemaphoreRights, AccessControlType)

Initializes a new instance of the SemaphoreAccessRule class, specifying the name of the user or group the rule applies to, the access rights, and whether the specified access rights are allowed or denied.

NameDescription
System_CAPS_pubpropertyAccessControlType

Gets the AccessControlType value associated with this AccessRule object.(Inherited from AccessRule.)

System_CAPS_protpropertyAccessMask

Gets the access mask for this rule.(Inherited from AuthorizationRule.)

System_CAPS_pubpropertyIdentityReference

Gets the IdentityReference to which this rule applies.(Inherited from AuthorizationRule.)

System_CAPS_pubpropertyInheritanceFlags

Gets the value of flags that determine how this rule is inherited by child objects.(Inherited from AuthorizationRule.)

System_CAPS_pubpropertyIsInherited

Gets a value indicating whether this rule is explicitly set or is inherited from a parent container object.(Inherited from AuthorizationRule.)

System_CAPS_pubpropertyPropagationFlags

Gets the value of the propagation flags, which determine how inheritance of this rule is propagated to child objects. This property is significant only when the value of the InheritanceFlags enumeration is not None.(Inherited from AuthorizationRule.)

System_CAPS_pubpropertySemaphoreRights

Gets the rights allowed or denied by the access rule.

NameDescription
System_CAPS_pubmethodEquals(Object)

Determines whether the specified object is equal to the current object.(Inherited from Object.)

System_CAPS_pubmethodGetHashCode()

Serves as the default hash function. (Inherited from Object.)

System_CAPS_pubmethodGetType()

Gets the Type of the current instance.(Inherited from Object.)

System_CAPS_pubmethodToString()

Returns a string that represents the current object.(Inherited from Object.)

The SemaphoreAccessRule class is one of a set of classes that the .NET Framework provides for managing Windows access control security on named system semaphores. For an overview of these classes, and their relationship to the underlying Windows access control structures, see SemaphoreSecurity.

System_CAPS_noteNote

Windows access control security is meaningful only for named system semaphores. If a Semaphore object represents a local semaphore, access control is irrelevant.

To get a list of the rules currently applied to a named semaphore, use the Semaphore.GetAccessControl method to get a SemaphoreSecurity object, then use its GetAccessRules method to obtain a collection of SemaphoreAccessRule objects.

SemaphoreAccessRule objects do not map one-to-one with access control entries in the underlying discretionary access control list (DACL). When you get the set of all access rules for a semaphore, the set contains the minimum number of rules currently required to express all the access control entries.

System_CAPS_noteNote

The underlying access control entries change as you apply and remove rules. The information in rules is merged if possible, to maintain the smallest number of access control entries. Thus, when you read the current list of rules, it might not look exactly like the list of all the rules you have added.

Use SemaphoreAccessRule objects to specify access rights to allow or deny to a user or group. A SemaphoreAccessRule object always represents either allowed access or denied access, never both.

To apply a rule to a named system semaphore, use the Semaphore.GetAccessControl method to get the SemaphoreSecurity object. Modify the SemaphoreSecurity object by using its methods to add the rule, and then use the Semaphore.SetAccessControl method to reattach the security object.

System_CAPS_importantImportant

Changes you make to a SemaphoreSecurity object do not affect the access levels of the named semaphore until you call the Semaphore.SetAccessControl method to assign the altered security object to the named semaphore.

SemaphoreAccessRule objects are immutable. Security for a semaphore is modified using the methods of the SemaphoreSecurity class to add or remove rules; as you do this, the underlying access control entries are modified.

System_CAPS_noteNote

Security on synchronization objects is not supported for Windows 98 or Windows Millennium Edition.

The following code example demonstrates the separation between Allow rules and Deny rules, and shows the combination of rights in compatible rules. The example creates a SemaphoreSecurity object, adds rules that allow and deny various rights for the current user, and displays the resulting pair of rules. The example then allows new rights for the current user and displays the result, showing that the new rights are merged with the existing Allow rule.

System_CAPS_noteNote

This example does not attach the security object to a Semaphore object. Examples that attach security objects can be found in Semaphore.GetAccessControl and Semaphore.SetAccessControl.

No code example is currently available or this language may not be supported.

.NET Framework
Available since 2.0

Any public static (Shared in Visual Basic) members of this type are thread safe. Any instance members are not guaranteed to be thread safe.

Return to top
Show: