CancelThreadpoolIo function (threadpoolapiset.h)

Cancels the notification from the StartThreadpoolIo function.

Syntax

void CancelThreadpoolIo(
  [in, out] PTP_IO pio
);

[in, out] pio

A pointer to a TP_IO structure that defines the I/O completion object. The CreateThreadpoolIo function returns this pointer.

None

To prevent memory leaks, you must call the CancelThreadpoolIo function for either of the following scenarios:

An overlapped (asynchronous) I/O operation fails (that is, the asynchronous I/O function call returns failure with an error code other than ERROR_IO_PENDING).
An asynchronous I/O operation returns immediately with success and the file handle associated with the I/O completion object has the notification mode FILE_SKIP_COMPLETION_PORT_ON_SUCCESS. The file handle will not notify the I/O completion port and the associated I/O callback function will not be called.

To compile an application that uses this function, define _WIN32_WINNT as 0x0600 or higher.

Requirement	Value
Minimum supported client	Windows Vista [desktop apps \| UWP apps]
Minimum supported server	Windows Server 2008 [desktop apps \| UWP apps]
Target Platform	Windows
Header	threadpoolapiset.h (include Windows.h on Windows 7, Windows Server 2008 Windows Server 2008 R2)
Library	Kernel32.lib
DLL	Kernel32.dll