Memory Problem?

[Peter Reid]

Hello Mark,

Thanks for the rapid and detailed response.  I'll have a play around  
with the things you suggest.  However, I did try much smaller chunks  
initially (250Kb) but found the external drive which is used to hold  
both partitions (source & destination) went somewhat berserk and the  
copying was considerably slower!  Given that the typical size of each  
backup file being copied is about 1.5Gb, 250Kb chunks would take too  
many cycles.  This is why I increased the chunk size up to 10Mb.

I'll take a look at your AppleScript and shell suggestions for  
setting the dates.

Thanks again.

Regards,

Peter

On 6 Feb 2007, at 11:53 pm, Mark Schonewille wrote:

> Hello Peter,
>
> I think that 10MB is quit a big chunk of data. Have you tried  
> smaller chunks as well? My experience is that smaller chunks give a  
> smoother impression, while they don't slow down copying much.
>
> I added a wait command to your code (see below).
>
> To get and set the modification dates on Mac OS X, use AppleScript.  
> To get the modification date (mind line wraps):
>
> tell application "Finder" to set x to the modification date of file  
> "System:Users:John:desktop:Untitled.html"
>
> To set the modification date:
>
> tell application "Finder" to set the modification date of file  
> "System:Users:John:desktop:Untitled.html copy" to date "31-10-2007"
>
> I believe that the date format needs to be the same as the system  
> date if you want to write a date in abbreviated form.
>
> AppleScript used by Revolution to copy modification dates:
>
> on copyDate theSourceFile,theDestinationFile
>   if char 1 of theSourceFile is "~" then delete char 1 of  
> theSourceFIle
>   if char 1 of theDestinationFile is "~" then delete char 1 of  
> theDestinationFile
>   put "tell application 'Finder'" & cr & ¬
>   "set myDate to the modification date of POSIX file '/users/" &  
> $USER & theSourceFile & "'" & cr & ¬
>   "set the modification date of POSIX file '/users/" & $USER &  
> theDestinationFile & "' to myDate" & cr & ¬
>   "end tell" into myScript
>   replace "'" with quote in myScript
>   do myScript as AppleScript
>   return the result
> end copyDate
>
>
> usage of the copyDate command:
>
> copyDate "~/desktop/Untitled.html","~/desktop/Untitled.html copy"
> put the result
>
> Note that the file paths need to be absolute file paths.
>
> Unfortunately, I expect that using AppleScript to set modification  
> dates may bring you back to the original problem, which was caused  
> by AppleScript locking up Revolution. A better alternative might be  
> to use a shell command, but I haven't looked into that yet. There  
> is a command line utility (GetFileInfo) included in Apple's  
> developer CD, which may be able to do the job.
>
> Best,
>
> Mark
>
> --
>
> Economy-x-Talk
> Consultancy and Software Engineering
> http://economy-x-talk.com
> http://www.salery.biz
>
> Get your store on-line within minutes with Salery Web Store  
> software. Download at http://www.salery.biz
>
> Op 6-feb-2007, om 23:24 heeft Peter Reid het volgende geschreven:
>
>> I've now managed to use buffered file copying for the problem I  
>> mentioned previously.  Here is my file copying handler:
>>
>> on copyAfile  sourceFile, destFolder, fCreatorType
>>   constant cBffrSize = 10485760 -- copy in 10Mbyte chunks
>>   set itemDelimiter to "/"
>>   put destFolder & last item of sourceFile into destFile
>>
>>   -- set the Mac OS filetype & create destination file:
>>   set the fileType to fCreatorType
>>   open file destFile for binary write
>>   -- open source file:
>>   open file sourceFile for binary read
>>
>>   -- copy the file data:
>>   put empty into dataBffr
>>   put false into gotEOF
>>   repeat until gotEOF
>>     read from file sourceFile for cBffrSize chars
>>     put the result is "eof" into gotEOF
>>     put it into dataBffr
>>     if dataBffr is not empty then
>>       write dataBffr to file destFile
>>     end if
> wait 0 millisecs with messages -- increase number for more control  
> over GUI
>>   end repeat
>>
>>   close file destFile
>>   close file sourceFile
>>
>>   -- copy Mac OS resource fork info:
>>   put getResources(sourceFile) into resourceList
>>   set itemDelimiter to comma
>>   repeat for each line i in resourceList
>>     put item 1 of i into resType
>>     put item 2 of i into resID
>>     put copyresource(sourceFile,destFile,resType,resID) into junk
> wait 0 millisecs with messages -- increase number for more control  
> over GUI
>>   end repeat
>>   put empty into junk
>> end copyAfile
>>
>> The remaining problem I have is that the copied file has the  
>> current time & date NOT the same time & date as the original  
>> file.  If I had used the revCopyFile, then the time & date would  
>> have been preserved.
>>
>> Can anyone suggest how I can change the (creation or modified)  
>> time & date on a file so the copies are the same as the originals?