AddMountingPoint Method

Adds a mounting point for the virtual drive.


int AddMountingPoint(const char* lpszMountingPoint, int iFlags, int64 lAuthenticationId);
INT AddMountingPoint(LPCWSTR lpszMountingPoint, INT iFlags, LONG64 lAuthenticationId);


This method adds a new mounting point for the virtual drive (which must have already been created using CreateStorage). Virtual drives may have as many mounting points as desired.

Typically, mounting points may be added before or after MountMedia is called. However, for plug-and-play virtual drives with non-removable media (see StorageType), AddMountingPoint must not be called until after the MountMedia method has been called successfully, otherwise an error will occur.

MountingPoint should be set to the name/path of the mounting point. The format of this value varies based what type of mounting point the application wishes to create; please refer to the Mounting Points topic for more information.

The Flags parameter is used to specify properties for the mounting point, and should be set by OR'ing together zero or more of the following flags:

STGMP_SIMPLE0x00010000Create a simple mounting point.

Simple mounting points may be local or global; and when local, can be made visible in either the current user session or another one.

This flag cannot be combined with STGMP_MOUNT_MANAGER or STGMP_NETWORK, and is implied if neither of those flags are present.

STGMP_MOUNT_MANAGER0x00020000Create a mounting point that appears to the system as a physical device.

When the StorageType property is set to STGT_DISK_PNP, mounting points created using the system mount manager appear as physical devices in the Disk Management snap-in of the Microsoft Management Console (mmc.exe).

This flag is a necessary prerequisite for creating a folder mounting point, which makes a drive accessible via an otherwise empty directory on another NTFS volume.

This flag cannot be combined with STGMP_SIMPLE, STGMP_NETWORK, or STGMP_LOCAL.

Only one mounting point of this type can be added to a virtual drive.

STGMP_NETWORK0x00040000Create a network mounting point.

Network mounting points can be further configured using the various STGMP_NETWORK_* flags described below. Applications that plan to make use of network mounting points must be sure to install the Helper DLL before doing so, otherwise Windows Explorer will not correctly recognize the "network" drive.

This flag cannot be combined with STGMP_SIMPLE or STGMP_MOUNT_MANAGER.

STGMP_LOCAL0x10000000Specifies that a local mounting point should be created.

This flag is supplementary, and specifies that a local mounting point should be created rather than a global one. When this flag is set, applications must also pass an appropriate value for the AddMountingPoint method's AuthenticationId parameter.

Passing 0 for AuthenticationId will make the mounting point visible in the current user session. To make the mounting point visible in a different user session instead, pass the target session's Authentication ID.

This flag is valid when combined with STGMP_SIMPLE or STGMP_NETWORK; it cannot be combined with STGMP_MOUNT_MANAGER. Please note that a mounting point can be made available to other computers as a network share, and network shares are always globally visible on the local machine, even if this flag is set.

STGMP_NETWORK_ALLOW_MAP_AS_DRIVE0x00000001Indicates that users may assign a drive letter to the share (e.g., using the 'Map network drive...' context menu item in Windows Explorer).

STGMP_NETWORK_HIDDEN_SHARE0x00000002Indicates that the share should be skipped during enumeration.

Such shares are only accessible when their name is already known to the accessor.

STGMP_NETWORK_READ_ACCESS0x00000004Makes a read-only share available for the mounting point.

When this flag is specified, the <Server Name> part of the MountingPoint parameter value must be empty. Please refer to the Mounting Points topic for more information.

STGMP_NETWORK_WRITE_ACCESS0x00000008Makes a read/write share available for the mounting point.

When this flag is specified, the <Server Name> part of the MountingPoint parameter value must be empty. Please refer to the Mounting Points topic for more information.

STGMP_NETWORK_CLAIM_SERVER_NAME0x00000010Specifies that the server name is unique.

When this flag is specified, the driver handles IOCTL_REDIR_QUERY_PATH[_EX] requests by instructing the OS to direct all requests going to the <Server Name> part of the MountingPoint parameter's value to the driver instead.

This flag should be used when the <Server Name> is unique within the local system (e.g., when the application's name is used). Using this flag allows the system to avoid delays caused by certain network requests made by various processes.

STGMP_DRIVE_LETTER_NOTIFY_ASYNC0x20000000Causes the method to return immediately without waiting for mounting notifications to be sent to the system.

STGMP_AUTOCREATE_DRIVE_LETTER0x40000000Tells the class that it should assign the drive letter automatically.

When this flag is specified, the class will automatically assign a drive letter from the list of available letters. The assigned letter is added to the end of the list of mounting points, and can be retrieved from there.

Do not include a drive letter in the MountingPoint parameter's value when specifying this flag.

If no flags are specified, the STGMP_SIMPLE flag is assumed.

If the STGMP_LOCAL flag is set, the AuthenticationId parameter should be set to the Authentication ID of the user session the mounting point should visible in; or to 0 to make the mounting point visible in the current user session. If the aforementioned flag is not set and AuthenticationId is 0, the mounting point will be global (i.e., visible in all user sessions). When AuthenticationId is set to a non-zero value, STGMP_LOCAL is implied. Please refer to the Mounting Points topic for more information.

Note: This method cannot be called within events.

The methods and properties related to mounting points are not intended to be used from multiple threads at once. Applications that wish to use said methods and properties from multiple threads are responsible for employing proper thread synchronization techniques to ensure that manipulation and enumeration of mounting points occurs in a thread-safe manner.

Virtual Drives, Media, and Mounting Points

When applications call the CreateStorage method, a virtual drive is created. Virtual drives are created without any "media" in them (like a CD drive without a CD inserted), and without any mounting points (drive letters, UNC paths, etc.).

After creating a virtual drive, applications should call MountMedia to "insert" virtual storage media into the virtual drive. This call will cause the class's events to start firing; applications must handle these events correctly, or the MountMedia call will fail.

Once media has been mounted in the virtual drive, applications should use the AddMountingPoint method to add one or more mounting points for the virtual drive. These mounting points make the virtual drive visible to the system and other applications, allowing them to start accessing the contents of the CBFS-based virtual filesystem.

Note that applications can technically call AddMountingPoint before MountMedia (except for plug-and-play virtual drives with non-removable media; see StorageType), but any attempts to access a virtual drive with no media mounted will result in a "no media" error.

Error Handling (C++)

This method returns a result code; 0 indicates success, while a non-zero error code indicates that this method encountered an error during its execution. If an error occurs, the GetLastError() method can be called to retrieve the associated error message. (Note: This method's result code can also be obtained by calling the GetLastErrorCode() method after it returns.)

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CBFS Connect 2020 C++ Edition - Version 20.0 [Build 7545]