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4/8/2010

This function suspends the execution of the current thread for a specified interval.

Syntax 

void Sleep(
  DWORD 
dwMilliseconds
);

Parameters

dwMilliseconds

[in] Specifies the time, in milliseconds, for which to suspend execution.

A value of zero causes the thread to relinquish the rest of its time slice to any other thread of equal priority that is ready to run. If no other threads of equal priority are ready to run, the function returns immediately, and the thread continues execution.

A value of INFINITE causes an infinite delay.

Return Value

None.

Remarks

A thread can relinquish the rest of its time slice by calling this function with a sleep time of zero milliseconds.

Calling Sleep(INFINITE )is different on Windows Embedded CE-based platforms than it is for Windows-based desktop platforms. For Windows Embedded CE-based platforms, Sleep(INFINITE )is equivalent to calling SuspendThread(GetCurrentThread()). This means that the thread suspend count is incremented from 0 to 1 and can be resumed, or woken up, by another thread that calls ResumeThreadon the sleeping thread. A Sleep(INFINITE )call on Windows-based desktop platforms is not a SuspendThreadcall, and calling ResumeThreadon the sleeping thread does not resume the thread.

Be careful when using Sleepand code that directly or indirectly creates windows. An example of code that indirectly creates windows is COM CoInitialize.

If a thread creates windows, it must process messages. Message broadcasts are sent to all windows in the system.

A thread that uses Sleepwith an infinite delay can cause the system to deadlock. Therefore, if you have a thread that creates windows, use MsgWaitForMultipleObjectsor MsgWaitForMultipleObjectsEx, instead of Sleep.

Some Windows Mobile devices have an internal capacitor or backup battery to allow for swapping the main battery while the device is in sleep mode without losing any device state information.

Requirements

Header winbase.h
Library coredll.lib
Windows Embedded CE Windows CE 1.0 and later
Windows Mobile Windows Mobile Version 5.0 and later

See Also