Difference between revisions of "Sleep without locking"
From HashVB
(Revert "claim") |
m (Made it a drop in replacement for the real sleep) |
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| Line 4: | Line 4: | ||
Private Declare Function GetTickCount& Lib "kernel32" () | Private Declare Function GetTickCount& Lib "kernel32" () | ||
| − | Private Declare Sub Sleep Lib "kernel32.dll" (ByVal dwMilliseconds As Long) | + | Private Declare Sub Sleep Alias "APISleep" Lib "kernel32.dll" (ByVal dwMilliseconds As Long) |
| − | Private Sub | + | Private Sub Sleep(ByVal dwMilliseconds As Long) |
Dim initTickCount As Long | Dim initTickCount As Long | ||
initTickCount = GetTickCount | initTickCount = GetTickCount | ||
Do Until GetTickCount - initTickCount >= dwMilliseconds | Do Until GetTickCount - initTickCount >= dwMilliseconds | ||
| − | + | APISleep 10 | |
'Use the API call for sleep to prevent 100% cpu usage | 'Use the API call for sleep to prevent 100% cpu usage | ||
DoEvents | DoEvents | ||
Revision as of 15:44, 3 September 2005
It is common in programming to need to have a timer of some form that will freeze your routine for a specified amount of time. One way to do this is to use the Sleep() API. Unfortunately there is a downside to this method, and that is that it will freeze your process. Not only does this mean that your APP's GUI updates will not occur until AFTER Sleep() returns, but also that your app will appear frozen to task manager.
So what's the solution? Why, create your own Sleep() function of course!
Private Declare Function GetTickCount& Lib "kernel32" () Private Declare Sub Sleep Alias "APISleep" Lib "kernel32.dll" (ByVal dwMilliseconds As Long)
Private Sub Sleep(ByVal dwMilliseconds As Long)
Dim initTickCount As Long
initTickCount = GetTickCount
Do Until GetTickCount - initTickCount >= dwMilliseconds
APISleep 10
'Use the API call for sleep to prevent 100% cpu usage
DoEvents
Loop
End Sub
This will freeze the routine from which it was called for the specified time, but leave the process free to update the GUI.
Simple as that.
