Password Salting Techniques
August 9th, 2009
This article is about using salting techniques to improve the security of authentication for websites. Examples are in PHP but the techniques apply to any language. Read more…
Archive
Archive for the ‘Computers’ Category
Missing tooltips in Firefox 3.5 and IE8
July 5th, 2009
I’ve just upgraded to Firefox 3.5 and noticed that tooltips had stopped working. I then checked Internet Explorer 8 and found tooltips were not working there either.
On investigation it seems that the two problems were unrelated, but here are the solutions to both of them…
Firefox 3.5
It seems there’s a bug in the Google Toolbar which can stop tooltips from working (you just get a small square instead). The fix is to uninstall Google Toolbar, then re-install it.
Internet Explorer 8
Bizarrely, this isn’t a bug. It’s a rare occasion when IE does the right thing according to the W3C spec. Basically, the HTML “alt” attribute has long been used to display tooltips over images, where in fact, it’s only supposed to be shown if the image doesn’t load. The correct attribute for displaying tooltips is actually the “title” attribute. Internet Explorer 8 has changed so that it works correctly according to the HTML spec.
What this means is that if a web page has only alt tags then in IE8 normal mode, you won’t see any tooltips. If however the page is in IE8 compatibility mode, you will see the tooltips.
Run SysInternals tools direct from the web
January 22nd, 2009
SysInternals tools are a fantastic set of free utilities written by Mark Russinovich and Bryce Cogswell. There are invaluable for system admins and Windows Power Users.
There is now a website that allows you to run most of the SysInternals tools directly, so you don’t have to find the right page, download it and unzip. You just run it directly from:
http://live.sysinternals.com/<tool>.exe
e.g.
http://live.sysinternals.com/procexp.exe
This works better in Internet Explorer than Firefox, since you can run the tool without saving it first.
DOS Equivalent of GREP
September 22nd, 2008
In Unix you can pipe the output of a command into the GREP command in order to only display the lines that contain a required string. This is means you don’t have to scroll through pages of output to find the bit you’re interested in. The DOS equivalent of GREP is FIND:
Searches for a text string in a file or files. FIND [/V] [/C] [/N] [/I] [/OFF[LINE]] "string" [[drive:][path]filename[ ...]] /V Displays all lines NOT containing the specified string. /C Displays only the count of lines containing the string. /N Displays line numbers with the displayed lines. /I Ignores the case of characters when searching for the string. /OFF[LINE] Do not skip files with offline attribute set. "string" Specifies the text string to find. [drive:][path]filename Specifies a file or files to search. If a path is not specified, FIND searches the text typed at the prompt or piped from another command.
this can be useful with the netstat command:
netstat -ano | find /i ":80"
or when viewing the DNS cache:
ipconfig /displaydns | find /i "google"
Although that isn’t ideal since the output of ipconfig isn’t really formatted to play nicely with the find command.
Reference: http://nzpcmad.blogspot.com/2007/07/dos-grep-equivalent-find-command.html
Windows XP DNS Cache
August 27th, 2008
Windows caches DNS responses to speed up network access, but sometimes this can cause a problem. Positive responses (i.e. successful lookups) are cached for 24 hours, and negative responses (i.e. failed lookups) for 5 minutes.
If you make changes to DNS and want to test the results straight away, you need to clear the cache with:
ipconfig /flushdns
You can view the current cache with:
ipconfig /displaydns
or
ipconfig /displaydns | more
to see a screen at a time
Mac OS X keyboard shortcuts
July 14th, 2008
Useful OS X keyboard shortcuts, particularly if you’re switching from Windows. It’s not exhaustive, but it’s got the ones I use regularly.
This page will be updated as I find new ones to include.
Recover Deleted Photos from Memory Card
July 6th, 2008
This article is written from the point of view of recovering deleted photos from a digital camera memory card, but most of the software will work to recover any type of file from any disk drive.
The first thing you must do is stop using the memory card. The more you use the card, the less likely that you will be able to recover the photos.
There are loads of free utilities that will recover photos, and I suggest trying them in the following order:
- Zero Assumption Recovery
- Full version is paid-for but the photo recovery option is free
- Download here
- Follow these instructions
- Recuva
- Download here
- Install it and follow the wizard which guides you through the recovery process
- Undelete Plus
- Download here
- Follow these instructions
If you’ve tried all of those and been unsuccessful, then I’m afraid it’s not looking very promising, but if you want to continue trying here are a few more utils:
Online & Peer-To-Peer Backup
June 20th, 2008
I’ve been assessing various backup options for both business and personal use recently so here’s a summary of my findings
Reduce Firefox Memory Usage
August 30th, 2007
Drag and drop an iTunes playlist’s songs into a folder
August 30th, 2007
from Lifehacker:
Regarding transferring songs out of iTunes, readers point out that you can select, drag and drop songs from iTunes to a Windows Explorer or Mac Finder window to copy them to a destination folder, a much easier method than Friday’s iTunes Export tack. However, the drag and drop method does NOT create an M3U playlist like iTunes Export does. Also, when I tested drag and drop on an extra large playlist (over a thousand songs), it refused to do a thing. For shorter lists it worked like a charm. Thanks, ‘hackers!
