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<concept id="GUID-1A8B20B3-CA6D-58A6-9DA0-8EB3965EDE7A" xml:lang="en"><title>How

to Detach and Re-attach a File</title><shortdesc>Explains how to detach and re-attach a file with the File Store.</shortdesc><prolog><metadata><keywords/></metadata></prolog><conbody>

<p>The file associated with a file store may be detached from the file store

and later re-attached. This behaviour is useful in cases where the file needs

to be closed and later re-opened ; for example, to give up a write lock for

backup purposes.</p>

<p>It is very important that the contents of the file should <i>not change</i> while

it is detached.</p>

<p>In the following code fragment, the file associated with the file store

is detached and closed; the file is then re-opened and re-attached to the

file store.</p>

<ol id="GUID-4E6D29CD-40E8-596A-B443-A6B5C1154AE5">

<li id="GUID-3EF9488A-3B84-5D17-B32A-CB7EE21A428E"><p>Use the <codeph>File()</codeph> member

function to retrieve a copy of the <codeph>RFile</codeph> object from the

file store.</p> </li>

<li id="GUID-81CF873E-51CD-509C-ABD7-E5A9DADE4181"><p>Use the <codeph>Detach()</codeph> member

function to detach the file store from the file and, in effect, give up ownership

of the file.</p> </li>

<li id="GUID-1ABA76DD-EAE1-5E3C-83FE-00F8DA6B256D"><p>Use the <codeph>Reattach()</codeph> member

function to re-attach a file to the file store and, in effect, take ownership

of that file.</p> </li>

</ol>

<codeblock id="GUID-494F23D9-6A61-53A0-995F-70CF227667B9" xml:space="preserve">LOCAL_C void doUseL(const TDesC&amp; aName)

    {

    TParse filestorename;

    ...

    fsSession.Parse(aName,filestorename);

    CFileStore* store = CPermanentFileStore::OpenLC (fsSession, filestorename.FullName(),EFileRead|EFileWrite );

    RFile thefile = store->File();

    store->Detach();

    thefile.Close();

    ...

    thefile.Open(fsSession, filestorename.FullName(),EFileRead|EFileWrite );

    store->Reattach(thefile);

    ...

    }</codeblock>