Wrong. I don't remember enabling anything crypto related in my kernel, but I use losetup with encryption to (wouldn't you know it) Encrypt my home directory.
In my physical home directory, there is a file containing the encrypted version. My.bashrc runs losetup, which prompts me for my passphrase, then mounts the encrypted home directory over the real one. Works flawlessly, and because the encrypted file is referenced by inode (not path), the kernel doesnt give a shit. When I logout it is simply unmounted and all is well.
Although it's probably not that likely, it's still possible that manipulating the bodys electric field could cause health problems. Anyone know if it could say, cause nerves to misfire or behave strangely? (Oscillating the electric field would theoretically create an electric charge in any nearby conductors (nerves), right?)
Zope gets surprisingly little mention in these sorts of discussions. Zope has...
* a persistant enterprise level object database, that handles a distributed backend completely transparently (so you dont have to use nasty hacks like hidden variables to store state data. The session data can store key-value pairs of any python object, and is duplicated across multiple servers using ZEO)
* Zope Page Templates Possibly the best templating language in existance, ZPT fullfills everything you need for your presentation layer.
* Python Scripting Zope supports python scripts and python products. Scripts are stored inside the ZODB and are generally used to help process data for page templates.
Python Products are where the meat of the processing happens. This is where you define your classes. Each class can be instantiated multiple time into the ZODB (i.e./sites/clienta AND/sites/clientb). So you can have the same codebase running two sites without setting up a seperate server.
* CMF and Plone Two out-of-the-box products available for Zope, CMF and Plone are probably the most powerfull content management systems known to man. You can extend these to your hearts content- I've created systems for under $1000 that were estimated at $50,000 by a J2EE development firm. I've consistantly been able to duplicate a weeks worth of J2EE in about a day of Zope.
I havn't even began to touch the full power of zope. It's really such an extreme difference in philosophy to J2EE or PHP design models that you need to experience it for yourself.
Python, Perl, PHP, Ruby... Thats four object orientated languages without strong typing, all of which have an extremely happy and loyal fanbase, and theres a lot more.
Just for once, I'd like to see someone explain why strong typing is so important. I develop most of my code in Python, and I have yet to see any problems. Hell, I find strong typing restrictive as it prevents me from doing things I otherwise should do. I'm currently working on a project of (according to cat | wc -l) 320812 lines, an god knows how many classes. I've yet to have one bug related to the lack of strong typing.
So heres my challange to all you strong typed zealots. Explain why it's so important!
True, a decent hacker could get in if he tried. I've been called in to recover about 15 compromised boxes before, and every single one was compromised by a rootkit. Since it's impossible to even get a shell, you pretty much can't run a rootkit.
most hack attempts are by 15 year olds with the latest 1337 tool. Change the system enough so the tools dont run, and you eliminate most of the threat and are left with the small percentage of experienced hackers who will persist. And even if they find an effective exploit, they can't do anything. The entire filesystem is read only at multiple levels (lids, chattr, mount, hdparm, bios). If they can get past that without a shell or any standard unix commands (keep in mind they can't upload anything, all daemons are running as non privilaged users, and LIDS locks down any chance of suid, kernel modules, and outgoing tcp), then... they are a freaking god.
I use obscurity as a "last tier" defence against hackers. If someone manages an exploit, they end up seeing my custom linux distro built from the ground up. And, literally, the only thing on my standard servers is apache and its immediate dependancys (libc, etc). I dont even have a shell installed.
Yeah sure. in THEORY, the server-client overhead of X slows it down. I have, however, yet to notice it. Hell, I get a Higher framerate with Quake3 in Linux than in win32.
To take the quake3 thing a bit further- one day I was setting up a quake3 server on a remote machine. However instead of running q3ded (the server), I ran quake3.x86 (the client) by mistake.
Imagine my horror when the screen goes blank and I realise what I have done, and SURELY, this would fsck both boxes. Theres no way quake3 can X over a 100mbit network link (with the overhead of SSH thrown in). Or can it?
A few seconds later up pops the menu. It ran fine. As a quick experiment, I loaded q3dm17. It worked, and I was getting a good 15fps- quite playable.
Dont believe me? try it for yourself.
I think that little demo alone is enough of a demonstration. X my have it's flaws- namely bloatedness, but it CERTAINLY doesn't seem slow to me.
I was commenting on the Graduate rates in America as posted by several other slashdot readers. I was then pointing out that the Australian rates were crappy in comparison- basicly what you said.
I currently work for $AU 30/hr (about $US15). This is considered pretty damn cheap, but I maintain that rate because I get a hell of a lot of work word-of-mouth.
Next year (after finishing university) I will have a lot of experience under my belt, a reputation for getting stuff done properly cheaply, and a lot of loyal clients.
I find it quite interesting to see references to "entry level" jobs being $50/hr or $50k/yr. Over here (in Australia) entry level IT jobs are generally around $AU30k/yr ($US15k), although I'm hoping to get around 50-70. Perhaps I should move to the states.
Ok lame jokes aside... Anybody here a fan of Stephen Baxter? In his book "Titan", they use something just like this called "Softscreens" which had pretty much replaced television, books, etc. I remember wishing someone would invent it.
Guess my wish came true.
So, I propose, we call this newfangled thingys Softscreens. In honour of Baxter and all. (Althogh I doubt he's the first one to come up with the idea:p)
Indeed. Object Databases will never replace Relational databases for that very reason (At least not in the forseeable future).
In the end, it comes down to the right tool for the right job. I can do things with Python Dictionarys that would be an absolute nightmare in J2EE + SQL, but I certainly couldn't maintain 30 tables of data with relationships and constraints and hope to have anything near an O(log n) search time..
I'm not suggesting people drop Mysql and start throwing all their data into the ZOBD- that would be a very stupid thing to do. what I AM suggesting is that people get out of the mindset of throwing everything into a database. In many projects, the database layer is the single most common point of failure- it's all too easy to make an error parsing data. An object persistance layer is quite often a better choice for many projects.
I did mention data integrity. the Zodb records all transactions, and rolls back to a known good state if something goes wrong. I presume this is what you were referring to.
As for the Join- This would depend on the circumstances. You could just make a call to a seperate dictionary/list to get the data using a field from one db as the key. Dictionarys do not equate directly to Relational Databases, so not everything has a direct analogy.
The Zodb is not a direct replacement for a Sequal database, however it can be used in most simple circumstances. I certainly wouldnt recommend storing 300 million accounting transactions in it.
The first thing you need to remember about the Zodb is that it's NOT a synonym for a relational database. You can use it to store the same kind of data, but you have to approach the problem from a completely different point of view.
At first people try and grasp how they would simulate tables, SQL queryies, etc. The answer is, you don't. If I want to store a large amount of records, I create a python dictionary (Think Java Hashtable, only better). I've written a 'product' called Shelf, which provides some simple APIs to do this. I can put dictionarys within dictionaries within dictionarys ad infinum, as well as lists, tuples, string, ints, whatever.
The 'query' language in this case, would be Python itself. Using list comprehension, I can search a dictionary of several hundred thousand records in a few hundred milliseconds.
i.e. return [(person['username'],person['password']) for person in staff if person.department in ['Marketing','Legal']]
Seems complex, but once you get the hang of it its more powerfull than SQL. (I can also write a normal python script to parse the data if need be).
Python supports several ways of allowing runtime parsing of code (ad-hoc querys, in this case).
When you modify data in zope, it records all transactions. If something fails, it rolls back the whole operation. You can also manually roll back any operation at a later date if you want. It also doesn't store the entire database in memory- it only loads whatever you access, and caches it for a period of time. This can all be tuned.
Zope supports spanning the ZODB over multiple servers. I've heard (although I'm still trying to confirm) of a Zope database containing over 300 gigabytes of information with no problems. I'll try and find a url.
The Zodb can only be accessed by zope, but all the code to do so is in a seperate module which can easily be imported into a standalone python session. On several occasions I've manually accessed the data using a python shell. You can also access the Zodb via FTP and WebDAV.
You can print a dictionary out as a string, save to a file, etc, and import into another python program at a later date using str() and eval(). This is trivial. Porting to other languages would require a little parsing, but is not out of the realms of possibility.
This sounds a lot like the Zope ZODB. For those who are still stuck in the stone age, Zope is a python based application server that essentially uses object serialisation to store its data.
Imagine if every page in your website was an object- with methods, properties, Access Control, etc. You have different classes for different types of documents, and each document internally knows how to render itself. The ZODB is essentially one big persistant object orientated namespace- You dont have to parse your data into SQL and back again, it's always just there, elimenating a huge amount of work (and bugs!). Having worked with it for a year, I can certainly testify that it is leaps and bounds over relational databases for most things.
Anyone whos ever done any serious web design will know that adhering to standards will get you nowhere. Every browser has its own way of rendering things and you almost always need to write "incorrect" code at some point to make them all happy.
IE in particular has some... "Interesting" ideas about how it should use CSS, and on many occasions I've had to use some very nasty hacks to work around them while keeping Mozilla happy.
(Hint: If you specify a parameter twice, IE will use the first one, Mozilla will use the last one. Mozilla also sees '//' as a comment while IE ignores it and reads the rest of the line)
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In your xinitrc you could do the same thing, except use gdialog to prompt for the password
It took me about 2 minutes to setup.
Wrong. I don't remember enabling anything crypto related in my kernel, but I use losetup with encryption to (wouldn't you know it) Encrypt my home directory.
.bashrc runs losetup, which prompts me for my passphrase, then mounts the encrypted home directory over the real one. Works flawlessly, and because the encrypted file is referenced by inode (not path), the kernel doesnt give a shit. When I logout it is simply unmounted and all is well.
In my physical home directory, there is a file containing the encrypted version. My
or you could just not use electromagnetically shielded carpet.
Although it's probably not that likely, it's still possible that manipulating the bodys electric field could cause health problems. Anyone know if it could say, cause nerves to misfire or behave strangely? (Oscillating the electric field would theoretically create an electric charge in any nearby conductors (nerves), right?)
Zope gets surprisingly little mention in these sorts of discussions. Zope has...
/sites/clienta AND /sites/clientb). So you can have the same codebase running two sites without setting up a seperate server.
* a persistant enterprise level object database, that handles a distributed backend completely transparently (so you dont have to use nasty hacks like hidden variables to store state data. The session data can store key-value pairs of any python object, and is duplicated across multiple servers using ZEO)
* Zope Page Templates
Possibly the best templating language in existance, ZPT fullfills everything you need for your presentation layer.
* Python Scripting
Zope supports python scripts and python products. Scripts are stored inside the ZODB and are generally used to help process data for page templates.
Python Products are where the meat of the processing happens. This is where you define your classes. Each class can be instantiated multiple time into the ZODB (i.e.
* CMF and Plone
Two out-of-the-box products available for Zope, CMF and Plone are probably the most powerfull content management systems known to man. You can extend these to your hearts content- I've created systems for under $1000 that were estimated at $50,000 by a J2EE development firm. I've consistantly been able to duplicate a weeks worth of J2EE in about a day of Zope.
I havn't even began to touch the full power of zope. It's really such an extreme difference in philosophy to J2EE or PHP design models that you need to experience it for yourself.
Python, Perl, PHP, Ruby... Thats four object orientated languages without strong typing, all of which have an extremely happy and loyal fanbase, and theres a lot more.
Just for once, I'd like to see someone explain why strong typing is so important. I develop most of my code in Python, and I have yet to see any problems. Hell, I find strong typing restrictive as it prevents me from doing things I otherwise should do. I'm currently working on a project of (according to cat | wc -l) 320812 lines, an god knows how many classes. I've yet to have one bug related to the lack of strong typing.
So heres my challange to all you strong typed zealots. Explain why it's so important!
True, a decent hacker could get in if he tried. I've been called in to recover about 15 compromised boxes before, and every single one was compromised by a rootkit. Since it's impossible to even get a shell, you pretty much can't run a rootkit.
most hack attempts are by 15 year olds with the latest 1337 tool. Change the system enough so the tools dont run, and you eliminate most of the threat and are left with the small percentage of experienced hackers who will persist. And even if they find an effective exploit, they can't do anything. The entire filesystem is read only at multiple levels (lids, chattr, mount, hdparm, bios). If they can get past that without a shell or any standard unix commands (keep in mind they can't upload anything, all daemons are running as non privilaged users, and LIDS locks down any chance of suid, kernel modules, and outgoing tcp), then... they are a freaking god.
I use obscurity as a "last tier" defence against hackers. If someone manages an exploit, they end up seeing my custom linux distro built from the ground up. And, literally, the only thing on my standard servers is apache and its immediate dependancys (libc, etc). I dont even have a shell installed.
Yeah sure. in THEORY, the server-client overhead of X slows it down. I have, however, yet to notice it. Hell, I get a Higher framerate with Quake3 in Linux than in win32.
To take the quake3 thing a bit further- one day I was setting up a quake3 server on a remote machine. However instead of running q3ded (the server), I ran quake3.x86 (the client) by mistake.
Imagine my horror when the screen goes blank and I realise what I have done, and SURELY, this would fsck both boxes. Theres no way quake3 can X over a 100mbit network link (with the overhead of SSH thrown in). Or can it?
A few seconds later up pops the menu. It ran fine. As a quick experiment, I loaded q3dm17. It worked, and I was getting a good 15fps- quite playable.
Dont believe me? try it for yourself.
I think that little demo alone is enough of a demonstration. X my have it's flaws- namely bloatedness, but it CERTAINLY doesn't seem slow to me.
I was commenting on the Graduate rates in America as posted by several other slashdot readers. I was then pointing out that the Australian rates were crappy in comparison- basicly what you said.
I currently work for $AU 30/hr (about $US15). This is considered pretty damn cheap, but I maintain that rate because I get a hell of a lot of work word-of-mouth.
Next year (after finishing university) I will have a lot of experience under my belt, a reputation for getting stuff done properly cheaply, and a lot of loyal clients.
I find it quite interesting to see references to "entry level" jobs being $50/hr or $50k/yr. Over here (in Australia) entry level IT jobs are generally around $AU30k/yr ($US15k), although I'm hoping to get around 50-70. Perhaps I should move to the states.
"Honey, can you fold the TV up and put it away?"
:p)
Ok lame jokes aside... Anybody here a fan of Stephen Baxter? In his book "Titan", they use something just like this called "Softscreens" which had pretty much replaced television, books, etc. I remember wishing someone would invent it.
Guess my wish came true.
So, I propose, we call this newfangled thingys Softscreens. In honour of Baxter and all. (Althogh I doubt he's the first one to come up with the idea
Indeed. Object Databases will never replace Relational databases for that very reason (At least not in the forseeable future).
In the end, it comes down to the right tool for the right job. I can do things with Python Dictionarys that would be an absolute nightmare in J2EE + SQL, but I certainly couldn't maintain 30 tables of data with relationships and constraints and hope to have anything near an O(log n) search time..
I'm not suggesting people drop Mysql and start throwing all their data into the ZOBD- that would be a very stupid thing to do. what I AM suggesting is that people get out of the mindset of throwing everything into a database. In many projects, the database layer is the single most common point of failure- it's all too easy to make an error parsing data. An object persistance layer is quite often a better choice for many projects.
I did mention data integrity. the Zodb records all transactions, and rolls back to a known good state if something goes wrong. I presume this is what you were referring to. As for the Join- This would depend on the circumstances. You could just make a call to a seperate dictionary/list to get the data using a field from one db as the key. Dictionarys do not equate directly to Relational Databases, so not everything has a direct analogy. The Zodb is not a direct replacement for a Sequal database, however it can be used in most simple circumstances. I certainly wouldnt recommend storing 300 million accounting transactions in it.
The first thing you need to remember about the Zodb is that it's NOT a synonym for a relational database. You can use it to store the same kind of data, but you have to approach the problem from a completely different point of view.
At first people try and grasp how they would simulate tables, SQL queryies, etc. The answer is, you don't. If I want to store a large amount of records, I create a python dictionary (Think Java Hashtable, only better). I've written a 'product' called Shelf, which provides some simple APIs to do this. I can put dictionarys within dictionaries within dictionarys ad infinum, as well as lists, tuples, string, ints, whatever.
The 'query' language in this case, would be Python itself. Using list comprehension, I can search a dictionary of several hundred thousand records in a few hundred milliseconds.
i.e. return [(person['username'],person['password']) for person in staff if person.department in ['Marketing','Legal']]
Seems complex, but once you get the hang of it its more powerfull than SQL. (I can also write a normal python script to parse the data if need be).
Python supports several ways of allowing runtime parsing of code (ad-hoc querys, in this case).
When you modify data in zope, it records all transactions. If something fails, it rolls back the whole operation. You can also manually roll back any operation at a later date if you want. It also doesn't store the entire database in memory- it only loads whatever you access, and caches it for a period of time. This can all be tuned.
Zope supports spanning the ZODB over multiple servers. I've heard (although I'm still trying to confirm) of a Zope database containing over 300 gigabytes of information with no problems. I'll try and find a url.
The Zodb can only be accessed by zope, but all the code to do so is in a seperate module which can easily be imported into a standalone python session. On several occasions I've manually accessed the data using a python shell. You can also access the Zodb via FTP and WebDAV.
You can print a dictionary out as a string, save to a file, etc, and import into another python program at a later date using str() and eval(). This is trivial. Porting to other languages would require a little parsing, but is not out of the realms of possibility.
This sounds a lot like the Zope ZODB. For those who are still stuck in the stone age, Zope is a python based application server that essentially uses object serialisation to store its data.
Imagine if every page in your website was an object- with methods, properties, Access Control, etc. You have different classes for different types of documents, and each document internally knows how to render itself. The ZODB is essentially one big persistant object orientated namespace- You dont have to parse your data into SQL and back again, it's always just there, elimenating a huge amount of work (and bugs!). Having worked with it for a year, I can certainly testify that it is leaps and bounds over relational databases for most things.
iiNET (QLD) has been up and down like a yoyo for the last few days. I guess this is why.
bla. forgot to use "Plain Text" mode. oops.
One more word Crossover (The WINE plugin for web browsers that runs ActiveX)
Anyone whos ever done any serious web design will know that adhering to standards will get you nowhere. Every browser has its own way of rendering things and you almost always need to write "incorrect" code at some point to make them all happy.
IE in particular has some... "Interesting" ideas about how it should use CSS, and on many occasions I've had to use some very nasty hacks to work around them while keeping Mozilla happy.
(Hint: If you specify a parameter twice, IE will use the first one, Mozilla will use the last one. Mozilla also sees '//' as a comment while IE ignores it and reads the rest of the line)