nf-oleauto-safearraylock.md

UID	title	description	helpviewer_keywords	old-location	tech.root	ms.assetid	ms.date	ms.keywords	req.header	req.include-header	req.target-type	req.target-min-winverclnt	req.target-min-winversvr	req.kmdf-ver	req.umdf-ver	req.ddi-compliance	req.unicode-ansi	req.idl	req.max-support	req.namespace	req.assembly	req.type-library	req.lib	req.dll	req.irql	targetos	req.typenames	req.redist	ms.custom	f1_keywords	dev_langs	topic_type	api_type	api_location	api_name
NF:oleauto.SafeArrayLock	SafeArrayLock function (oleauto.h)	Increments the lock count of an array, and places a pointer to the array data in pvData of the array descriptor.	SafeArrayLock SafeArrayLock function [Automation] _oa96_SafeArrayLock automat.safearraylock oleauto/SafeArrayLock	automat\safearraylock.htm	automat	cb29d862-c7c5-4852-b017-c29e88d5f1c4	12/05/2018	SafeArrayLock, SafeArrayLock function [Automation], _oa96_SafeArrayLock, automat.safearraylock, oleauto/SafeArrayLock	oleauto.h		Windows												OleAut32.lib	OleAut32.dll		Windows			19H1	SafeArrayLock oleauto/SafeArrayLock	c++	APIRef kbSyntax	DllExport	OleAut32.dll	SafeArrayLock

SafeArrayLock function

-description

Increments the lock count of an array, and places a pointer to the array data in pvData of the array descriptor.

-parameters

-param psa [in]

An array descriptor created by SafeArrayCreate.

-returns

This function can return one of these values.

Return code	Description
S_OK	Success.
E_INVALIDARG	The argument psa is not valid.
E_UNEXPECTED	The array could not be locked.

-remarks

The pointer in the array descriptor is valid until the SafeArrayUnlock function is called. Calls to SafeArrayLock can be nested, in which case an equal number of calls to SafeArrayUnlock are required.

An array cannot be deleted while it is locked.

Thread Safety

All public static (Shared in Visual Basic) members of the SAFEARRAY data type are thread safe. Instance members are not guaranteed to be thread safe.

For example, consider an application that uses the SafeArrayLock and SafeArrayUnlock functions. If these functions are called concurrently from different threads on the same SAFEARRAY data type instance, an inconsistent lock count may be created. This will eventually cause the SafeArrayUnlock function to return E_UNEXPECTED. You can prevent this by providing your own synchronization code.