Celebrate National IT Professionals Day with 3 months of free Premium Membership. Use Code ITDAY17

x
?
Solved

Filemodes with Assignfile and Reset

Posted on 2001-07-16
9
Medium Priority
?
1,260 Views
Last Modified: 2012-05-04
Hi, Im using AssignFile and Reset in my application, and this seems to cause a problem. I need to be able to copy the opened files (for backup) when the application is running, and I cant do that! They are locked. I've looked at the global variable FileMode, but the default is already the least restricted, namely Read/Write. I could of course use a stream, and change all my calls, but it's a lot of calls... So, is it possible to open with other filemodes, when using Reset?

Pede
0
Comment
Question by:pede
[X]
Welcome to Experts Exchange

Add your voice to the tech community where 5M+ people just like you are talking about what matters.

  • Help others & share knowledge
  • Earn cash & points
  • Learn & ask questions
9 Comments
 
LVL 27

Expert Comment

by:kretzschmar
ID: 6285386
maybe it helps

if you open the file in readonly-mode
0
 
LVL 1

Author Comment

by:pede
ID: 6285410
I need to be able to write to the files, so that's not an option :0( I know this could cause problems if Im writing to the file while backing up, but it's not a huge problem in my application.


0
 
LVL 17

Accepted Solution

by:
geobul earned 150 total points
ID: 6285453
Hi,
I don't understand why you can't copy these files. Reset opens files for read/write but they are still readable by other apps (including copying).

Regards, Geo
0
Independent Software Vendors: We Want Your Opinion

We value your feedback.

Take our survey and automatically be enter to win anyone of the following:
Yeti Cooler, Amazon eGift Card, and Movie eGift Card!

 
LVL 2

Expert Comment

by:bugroger
ID: 6285476
HI,

I think the best will be to use

 CreateFile, Read/WriteFile, CloseHandle

and change all your calls !

GL
 BUG
0
 
LVL 1

Author Comment

by:pede
ID: 6285602
I cant copy the files using the program PcAnyWhere, thats why I thought they where opened in the wrong way. It seems that PcAnyWhere can't copy any files at all, if another progam are using them. I tried to make a new Word document, opened it with Word and made a copy of the file. No problems. Then I tried to copy it with PcAnyWhere, and it failed.

Points goes to Geobul, since his comment made me try this.

Pede
0
 
LVL 44

Expert Comment

by:CrazyOne
ID: 6286367
Yeah I have been wondering about this myself. I am using Win 2000 and when I was using Win 98 I could use xcopy directly to backup the registry but in Win 2000 it doesn't work because the registry files are locked down. I have yet to find away to do it programmically but I know it is possible because the Win 2000 backup utility does it. So if anybody has a solution to this I will award 100 points to them myself. :>)


The Crazy One
0
 

Expert Comment

by:ms99
ID: 6287686
Hi Pede,

These constants control the way you open a file:

const fmOpenRead       = $0000;
const fmOpenWrite      = $0001;
const fmOpenReadWrite  = $0002;

const fmShareCompat    = $0000;
const fmShareExclusive = $0010;
const fmShareDenyWrite = $0020;
const fmShareDenyRead  = $0030;
const fmShareDenyNone  = $0040;

Besides opening for read/write you must also set Filemode to fmShareDenyNone or fmShareDenyWrite to let other applications read your files:

assignFile(f,'file.dat');
filemode := fmOpenReadWrite or fmShareDenyNone;
reset(f);


0
 
LVL 14

Expert Comment

by:DragonSlayer
ID: 6288137
I didn't try it, but was just wondering... perhaps a MemoryStream can do it?
0
 
LVL 1

Author Comment

by:pede
ID: 6289028
Im sorry I forgot to assign the points, but the question is closed already. But some nice info there, ms99. The Delphi help didn't include all those constants.
0

Featured Post

Free Tool: Subnet Calculator

The subnet calculator helps you design networks by taking an IP address and network mask and returning information such as network, broadcast address, and host range.

One of a set of tools we're offering as a way of saying thank you for being a part of the community.

Question has a verified solution.

If you are experiencing a similar issue, please ask a related question

Introduction The parallel port is a very commonly known port, it was widely used to connect a printer to the PC, if you look at the back of your computer, for those who don't have newer computers, there will be a port with 25 pins and a small print…
Introduction Raise your hands if you were as upset with FireMonkey as I was when I discovered that there was no TListview.  I use TListView in almost all of my applications I've written, and I was not going to compromise by resorting to TStringGrid…
Video by: ITPro.TV
In this episode Don builds upon the troubleshooting techniques by demonstrating how to properly monitor a vSphere deployment to detect problems before they occur. He begins the show using tools found within the vSphere suite as ends the show demonst…
Visualize your data even better in Access queries. Given a date and a value, this lesson shows how to compare that value with the previous value, calculate the difference, and display a circle if the value is the same, an up triangle if it increased…
Suggested Courses

730 members asked questions and received personalized solutions in the past 7 days.

Join the community of 500,000 technology professionals and ask your questions.

Join & Ask a Question