FlsGetValue function (fibersapi.h)

Retrieves the value in the calling fiber's fiber local storage (FLS) slot for the specified FLS index. Each fiber has its own slot for each FLS index.


PVOID FlsGetValue(
  [in] DWORD dwFlsIndex


[in] dwFlsIndex

The FLS index that was allocated by the FlsAlloc function.

Return value

If the function succeeds, the return value is the value stored in the calling fiber's FLS slot associated with the specified index.

If the function fails, the return value is NULL. To get extended error information, call GetLastError.


FLS indexes are typically allocated by the FlsAlloc function during process or DLL initialization. After an FLS index is allocated, each fiber of the process can use it to access its own FLS slot for that index. A fiber specifies an FLS index in a call to FlsSetValue to store a value in its slot. The thread specifies the same index in a subsequent call to FlsSetValue to retrieve the stored value.


Minimum supported client Windows Vista [desktop apps | UWP apps]
Minimum supported server Windows Server 2003 [desktop apps | UWP apps]
Target Platform Windows
Header fibersapi.h
Library Kernel32.lib
DLL Kernel32.dll

See also




Process and Thread Functions