https://forge.codesys.com/forge/talk/Engineering/thread/827be8e057/2020-02-27T13:54:56.048000ZRecent posts to File Access Problem2020-02-27T13:54:56.048000Z2020-02-27T13:54:56.048000Ztimvhhttps://forge.codesys.com/u/timvh/https://forge.codesys.com6cf77a76c03b42b9fa17683d2969f9132c5964fa

<div class="markdown_content"><p>As I understand it correctly, what you say is in both cases the same.</p></div>

2020-02-27T13:54:55.840000Z2020-02-27T13:54:55.840000Zyue-qi-qihttps://forge.codesys.com/u/yue-qi-qi/https://forge.codesys.coma30c72aae299b72f3209ac113d45d245f2c12689

<div class="markdown_content"><p>I have just download the CoDeSys Examples of “FileUtilities”，that writes as：</p> <p>IF xInit THEN<br/> CASE iState OF<br/> 0: //Open the specified file with write access.<br/> FileOpen(xExecute:= TRUE, sFileName:= sFileName, xExclusive:= FALSE, eFileMode:= File.MODE.MWRITE );<br/> IF FileOpen.xDone = TRUE THEN<br/> iState := 1;<br/> hfile := FileOpen.hFile;<br/> FileOpen(xExecute:= FALSE);<br/> ELSIF FileOpen.xError = TRUE THEN<br/> iState:= 32767;<br/> FileOpen(xExecute:= FALSE);<br/> END_IF<br/> ...</p> <p>The code above is tested on CoDeSys Control Win V3, and if there has exist a file which the sFileName specifies, and the file size is not 0, but after the above FileOpen() function executed and success with xFone=TRUE.the file size is 0, which means the file which is open with File.MODE.MWRITE mode will be cleared to empty!<br/> In my mind, if you open the file with File.MODE.MWRITE, if the file does not exists, the file will be created and opened;and if the file has existed, then the file will be opened and should be cleared to empty!<br/> But the test above shows that open a file with File.MODE.MWRITE mode means create a new file or clear an existing file to empty!</p></div>

2020-02-27T13:54:55.644000Z2020-02-27T13:54:55.644000Zyue-qi-qihttps://forge.codesys.com/u/yue-qi-qi/https://forge.codesys.com246f2f99a9edad5b37fbeb1620eb6cc039c673d6

<div class="markdown_content"><p>I meet a problem when I use the File Access 3.4.1.0 library to operate file access.<br/> fbFileOpen:FILE_ACCESS.FILE.Open;<br/> fbFileOpen(xExecute:=TRUE,sFileName:=strFileName,eFileMode:=FILE_ACCESS.FILE.MODE.MWRITE,xExclusive:=FALSE);<br/> after fbFileOpen() executed,the content of the file that the function block open will be cleard! And the size of the file will be 0!</p></div>