{"id":1909,"date":"2009-09-11T09:31:37","date_gmt":"2009-09-11T13:31:37","guid":{"rendered":"http:\/\/nuxx.net\/blog\/?p=1909"},"modified":"2009-09-11T09:39:49","modified_gmt":"2009-09-11T13:39:49","slug":"changing-win32_operatingsystem-lastbootuptime-result-on-xp-sp2-after-stand-by-or-hibernate","status":"publish","type":"post","link":"https:\/\/nuxx.net\/blog\/2009\/09\/11\/changing-win32_operatingsystem-lastbootuptime-result-on-xp-sp2-after-stand-by-or-hibernate\/","title":{"rendered":"Changing Win32_OperatingSystem.LastBootupTime Result on XP SP2 after Stand-By or Hibernate"},"content":{"rendered":"

On Windows XP one can use WMI<\/a> to determine when the computer booted up by querying root\/cimv2\/Win32_OperatingSystem.LastBootupTime<\/tt>. This will return a result in CIM_DATETIME<\/a> format indicating the time the computer booted up. However, while researching some things yesterday I found that on XP SP2 this changes if a user logs out, puts the computer in a Hibernate or Stand-by mode, wakes the computer, then queries this value.<\/p>\n

Here’s results of this query after a few different scenarios:<\/p>\n

Initial Query: 20090910130529.109375-240
\nAfter Logoff \/ Logon: 20090910130529.109375-240
\nAfter Hibernate \/ Wake while Logged In: 20090910130529.109375-240
\nAfter Logoff \/ Hibernate \/ Wake \/ Login: 20090910131221.162894<\/u>-240
\nAfter Logoff \/ Stand By \/ Wake \/ Login: 20090910131718.006644<\/u>-240<\/p><\/blockquote>\n

This was quite unexpected, because Microsoft’s documentation on the Win32_OperatingSystem class<\/a> states that LastBootUpTime<\/tt> contains “Date and time the operating system was last restarted.”, and Hibernate or Stand By shouldn’t constitute a restart.<\/p>\n

This behavior was not observed on XP SP3. Per 946480: List of fixes that are included in Windows XP Service Pack 3<\/a> this was not something fixed, but it does appear to have changed. If you would like to demonstrate this for yourself, use the following VBScript (or download it from here: getlastbootuptimetest.vbs<\/a>) to easily read out Win32_OperatingSystem.LastBootUpTime<\/tt>:<\/p>\n

<\/p>\n

Option Explicit<\/tt><\/p>\n

Dim colQueryResults<\/tt>
\nDim dteLastBootupTime<\/tt>
\nDim objItem<\/tt>
\nDim objWMI<\/tt><\/p>\n

Set objWMI = GetObject(\"winmgmts:root\\cimv2\")<\/tt><\/p>\n

Set colQueryResults = objWMI.ExecQuery(\"Select LastBootUpTime from Win32_OperatingSystem\")<\/tt><\/p>\n

For Each objItem in colQueryResults<\/tt>
\n    dteLastBootupTime = objItem.LastBootUpTime<\/tt>
\nNext<\/tt><\/p>\n

If InStr(1,Wscript.FullName,\"cscript.exe\",1) = 0 Then<\/tt>
\n    MsgBox \"Win32_OperatingSystem.LastBootupTime in CIM Format:\" & vbCRLF & dteLastBootupTime, vbOKOnly, \"Result!\"<\/tt>
\nElse<\/tt>
\n    WScript.Echo<\/tt>
\n    WScript.Echo \"Win32_OperatingSystem.LastBootupTime in CIM Format is:\"<\/tt>
\n    WScript.Echo dteLastBootupTime<\/tt>
\nEnd If<\/tt><\/p><\/blockquote>\n","protected":false},"excerpt":{"rendered":"

On Windows XP one can use WMI to determine when the computer booted up by querying root\/cimv2\/Win32_OperatingSystem.LastBootupTime. This will return a result in CIM_DATETIME format<\/p>\n

Continue readingChanging Win32_OperatingSystem.LastBootupTime Result on XP SP2 after Stand-By or Hibernate<\/span><\/a><\/div>\n","protected":false},"author":2,"featured_media":0,"comment_status":"open","ping_status":"open","sticky":false,"template":"","format":"standard","meta":{"footnotes":""},"categories":[13],"tags":[],"class_list":["post-1909","post","type-post","status-publish","format-standard","hentry","category-computers","entry"],"amp_enabled":true,"_links":{"self":[{"href":"https:\/\/nuxx.net\/blog\/wp-json\/wp\/v2\/posts\/1909","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/nuxx.net\/blog\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/nuxx.net\/blog\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/nuxx.net\/blog\/wp-json\/wp\/v2\/users\/2"}],"replies":[{"embeddable":true,"href":"https:\/\/nuxx.net\/blog\/wp-json\/wp\/v2\/comments?post=1909"}],"version-history":[{"count":10,"href":"https:\/\/nuxx.net\/blog\/wp-json\/wp\/v2\/posts\/1909\/revisions"}],"predecessor-version":[{"id":1919,"href":"https:\/\/nuxx.net\/blog\/wp-json\/wp\/v2\/posts\/1909\/revisions\/1919"}],"wp:attachment":[{"href":"https:\/\/nuxx.net\/blog\/wp-json\/wp\/v2\/media?parent=1909"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/nuxx.net\/blog\/wp-json\/wp\/v2\/categories?post=1909"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/nuxx.net\/blog\/wp-json\/wp\/v2\/tags?post=1909"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}