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Posted: **Thu Sep 16, 2004 8:03 am**

The following monitors a folder and advises on changes.

Questions of a technical nature will be ignored due to ignorance on my part.

Comments, suggestions, improvements and (if this is not good or safe) warnings are requested.

Hope it is ok, and hope it is useful.

Code: Select all

; Monitor changes to a folder, by Dare2
; First test
; Windows 2K and PB3.91
;
; Change "pth" var below to hold a folder name
; Do something to the folder, eg,
; Copy in a file then delete it.
;
; If your windows are crowded you might
; have to hunt for the messagebox!  :)


#STATUS_WAIT_0=$00000000            ; Taken from windows inc
#STATUS_ABANDONED_WAIT_0=$00000080  ; Not all are used here.
#STATUS_USER_APC=$000000C0
#STATUS_TIMEOUT=$00000102

#WAIT_FAILED=-1
#WAIT_OBJECT_0=#STATUS_WAIT_0
#WAIT_ABANDONED=#STATUS_ABANDONED_WAIT_0
#WAIT_ABANDONED_0=#STATUS_ABANDONED_WAIT_0
#WAIT_TIMEOUT=#STATUS_TIMEOUT
#WAIT_IO_COMPLETION=#STATUS_USER_APC

fHnd.l

;                                          Decide which notifications
flgs=0
flgs=flgs | #FILE_NOTIFY_CHANGE_FILE_NAME
flgs=flgs | #FILE_NOTIFY_CHANGE_FILE_NAME
flgs=flgs | #FILE_NOTIFY_CHANGE_DIR_NAME
flgs=flgs | #FILE_NOTIFY_CHANGE_ATTRIBUTES
flgs=flgs | #FILE_NOTIFY_CHANGE_SIZE
flgs=flgs | #FILE_NOTIFY_CHANGE_LAST_WRITE
flgs=flgs | #FILE_NOTIFY_CHANGE_SECURITY

pth.s="C:\aFolder\path\required\"
fHnd=FindFirstChangeNotification_(pth,#False,flgs)
If fHnd=#INVALID_HANDLE_VALUE
  MessageRequester("ERROR","FirstChange returned "+Str(GetLastError_()),#MB_ICONSTOP)
  End
EndIf

;                            Only watches for 1 minute or 2 events, which is sooner.
timeout=60000
tm=GetTickCount_()+timeout
While ctr<2 And tm>GetTickCount_()
  res.l=FindNextChangeNotification_(fHnd)  ; Advise we want a notification
  If res=#False
    MessageRequester("ERROR","NextChange returned "+Str(GetLastError_()),#MB_ICONSTOP)
    ctr=3
  Else
;                           Wait for notification
    chng=WaitForSingleObject_(fHnd,timeout)   ;#INFINITE)
    ctr+1
    If chng=#WAIT_OBJECT_0
      MessageRequester("NOTICE!","Change Notification!",#MB_ICONEXCLAMATION)
    Else
      MessageRequester("NOTICE!","ANOTHER EVENT!",#MB_ICONSTOP)
    EndIf
    res.l=FindNextChangeNotification_(fHnd)
    If res=#False
      MessageRequester("ERROR","NextChange returned "+Str(GetLastError_()),#MB_ICONSTOP)
      ctr=3
    EndIf
  EndIf
Wend
res=FindCloseChangeNotification_(fHnd)

Still have to try monitoring multiple folders via:
WaitForMultipleObjects_(count,AddressOfArrayOfHandles,#False,timeout)

Posted: **Thu Sep 16, 2004 11:08 am**

Thanks for sharing! It's very useful for my current project :) thx.

cya dige

Posted: **Fri Sep 17, 2004 11:50 am**

Thanks dare2 it's great work

Posted: **Fri Sep 17, 2004 2:41 pm**

Thanks.

Still to do the multiple objects.

Also stuck on a way to monitor changes to registry in general (can only see approaches that monitor a specific key).

Posted: **Fri Sep 17, 2004 6:15 pm**

my memroy is failing me (as usual

) but there was some api that handled / flagged / monitored directories, and it wasn't the one you used... if i find the sample back i'll post it

Posted: **Sat Sep 18, 2004 12:02 am**

Appreciate that.

The single item wait I'm using is, I read, a begger on the queues and can degrade performance unless short time outs, etc.

PureBasic Forums - English

Here is a Folder Change monitor (win)

Here is a Folder Change monitor (win)