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4/8/2010

This function retrieves information about the first thread of a process encountered in a system snapshot.

Syntax 

BOOL WINAPI Thread32First(
  HANDLE
 hSnapshot,
  LPTHREADENTRY32
 lpte
);

Parameters

hSnapshot

[in] Handle to the snapshot returned from a previous call to the CreateToolhelp32Snapshotfunction.

lpte

[out] Pointer to a THREADENTRY32structure.

Return Value

TRUE indicates that the first entry of the thread list has been copied to the buffer. FALSE indicates failure. The ERROR_NO_MORE_FILES error value, returned by GetLastError, indicates that no threads exist or the snapshot does not contain thread information.

Remarks

The calling application must set the dwSizemember of THREADENTRY32to the size, in bytes, of the structure. Thread32Firstchanges dwSizeto the number of bytes written to the structure. This number is never greater than the initial value of dwSize, but it can be smaller. If the value is smaller, do not rely on the values of members whose offsets are greater than this value. To retrieve information about other threads recorded in the same snapshot, use the Thread32Nextfunction.

Requirements

Header tlhelp32.h
Library toolhelp.lib
Windows Embedded CE Windows CE 2.0 and later
Windows Mobile Windows Mobile Version 5.0 and later

See Also