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Archive for the ‘BSD’ Category

Using kqemu in debian

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kqemu is not available in any of official debian repos. (Google “kqemu” if you dont know what kqemu is. Also kqemu on wikipedia).

So, if your machine doesnot supports KVM (like mine), you’ll most probably feel the need of kqemu. To install kqemu on debian (confirmed on lenny), follow these:

NOTE: Run all commands below as root.

apt-get install module-assistant
m-a prepare
m-a update
m-a a-i kqemu

After this, open /etc/modules in you text editor and append kqemu after last line (mind you, there should be no other text in that line) i.e. append this line to /etc/modules:

kqemu

Now, restart your system and launch an OS inside qemu *as root* (kqemu wont be loaded with qemu if you are not root).

That’s it πŸ™‚

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Written by Amber Jain

July 1, 2010 at 11:20 PM

g++ warnings on OpenBSD: “strcpy() is almost always misused, please use strlcpy()” and “strcat() is almost always misused, please use strlcat()”

with 4 comments

strcpy() and strcat() related warnings on OpenBSD with gcc/g++

I have a box with OpenBSD 4.5 installed. When compiling c++ programs using g++, I get following warnings:

/usr/lib/libstdc++.so.47.0: warning: strcpy() is almost always misused, please use strlcpy()
/usr/lib/libstdc++.so.47.0: warning: strcat() is almost always misused, please use strlcat()
Well, “Unix Programming Tools” from Stanford’s website says:
“Getting used to compiles that produce “a few warnings” is a very bad habit”.

I asked the reason for these warnings on ##c++-basic on irc.freenode.net. The guys there suggested me some options (e.g. -Wno-deprecated, -Wno-deprecated-declarations)

Then somehow this thought strike my mind. What if this has something to do with ‘propolice’? OR What if this is OpenBSD related issue (?) OpenBSD strives hard to be secure. Although, not all OpenBSD packages go through rigorous security audit, but then gcc is something that is likely to be ‘modified’ to fit OpenBSD’s goals. So, I asked this on #openbsd (at freenode). Here’s the IRC log:

AmberJ> Why does gcc/g++ outputs 2 warnings: “strcpy() is almost always misused, please use strlcpy() [and the same with strcat]”….Is it because openbsd has propolice enabled?
….because I don’t seem to encounter those warnings on other OSes with propolice disabled
AmberJ: it’s a linking warning, you’ll only see it when you link something that uses strcpy() etc
oenone, But why those warnings pop up only on OpenBSD ?
AmberJ: because other OSes don’t have the warnings in their version of libc

I updated this info to ##c++-basic. IRC-log:

AmberJ> That’s it! I hope that is the answer to my original question
jps_77, SukhE metabol Leoneof` thanks all πŸ™‚
AmberJ: that was a retarded reply that you got in #openbsd
try in #gcc

I then tried at #gcc as suggested(at freenode). IRC log:

AmberJ> Why does gcc/g++ outputs 2 warnings: “strcpy() is almost always misused, please use strlcpy() [and the same with strcat]”….Is it because openbsd has propolice enabled?
I’m using gcc 3.3.5 (propolice)
Ofcourse, I’m using OpenBSD 4.5
AmberJ: that sounds a lot like OpenBSD broke it. (they invented those l forms)
noshadow, Someone at #openbsd mentioned: “Other OSes don’t hae similar warnings because other OSes don’t have the warnings in their version of libc”
AmberJ: yes, that’s a possible place where they could have put those uncessary warnings.
noshadow, ok ty πŸ™‚
though the warning is really the wrong way round. why strcpy is usefull often, strlcpy is always always misused…
ok

Ofcourse, you can feel the ‘anti-openbsd’ feeling in the air πŸ˜‰

In the end, the folks at ##c++-basic suggested me that I try to install a newer version of gcc i.e. 4.x (mind you, gcc/g++ 3.3.5-propolice is the version that is shipped with OpenBSD 4.5) and if this problem persists (Is this really a problem? Read this. I suppose the warning is apt.), they suggested that I try to compile gcc from source.

More soon.

πŸ™‚

Written by Amber Jain

January 9, 2010 at 1:24 PM

OpenBSD Docs

with 2 comments

Written by Amber Jain

November 30, 2009 at 4:09 PM

Posted in Openbsd

Tagged with , ,

Adobe Flash on OpenBSD

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Hello,

I personally prefer to download youtube etc. videos first and then watch them using Mplayer etc. but here are some useful links if you really want to use Adobe Flash on OpenBSD:

Link 1
Link 2
Link 3

Update 1: swfdec (http://swfdec.freedesktop.org/wiki/) is also an option other than gnash on OpenBSD (or atleast it seems so) although I have not personally tried swfdec).

Update 2: http://www.bluelife.at/blog/articles/20100724-geckomediaplayer_as_Flash_Alternative_for_YouTube/
http://sourceforge.net/projects/lightspark/
Planning to rearrange stuff. Soon.
πŸ™‚

Written by Amber Jain

November 12, 2009 at 5:20 AM

Posted in Openbsd

Tagged with , , ,

Recursively search sub-directories in a directory to delete a file with a specific name

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Hello,

@Windows OS users: Sometimes when a malware simply installs itself recursively in all the sub-directories (starting from root i.e. C:) with the same name, you need to delete each file. Manual deletion is not usually possible when there are thousands of malware files. This could prove useful to you.
And yes, use some ‘better’ OS if you can.

On ##unix at irc.freenode.net, someone (justinko) asked a question that goes like:
Que: How to recursively search all sub-directories in a directory to delete a file with a specific name?

Answer: Rather than providing only the answer, I prefer putting the complete IRC log here (mind you, ‘justinko’ and ‘Riviera’ are the nicks of persons involved in this conversation):
justinko how do I delete a file in every sub directory?
justinko im in a directory that has directores, and inside those directories there is one file that needs to be deleted
Riviera with a particular name?
justinko yes
justinko I know the exact file name
Riviera okay
Riviera find directory/ -type f -name 'exact_filename' -exec rm -f -- {} +
justinko is find a command?
Riviera yes
justinko the sub-directories are all named differently
Riviera some finds (actually I only know about GNU find) even have the primary -delete
Riviera yes
Riviera i figured
Riviera The find command I gave you recusively checks all files in the "directory/" hierarchy for files with the name "exact_filename",
Riviera executing the command "rm -f --" with the found pathnames as parameters.
Riviera recursively*
Riviera If you want to learn more about find, read this: http://mywiki.wooledge.org/UsingFind
Riviera note that some of the examples given there are related to the bash-shell.
justinko damn that worked
Riviera I'm glad :)
justinko what is - type f ?
justinko I know rm -f is "force remove"
Riviera restricts the filetype to "ordinary files"
justinko k
justinko what does {} mean?
Riviera so that even if you'd have directories with the same name as the files you wish to remove, would be left alone
Riviera when find starts the command given after the -exec primary
Riviera (which, in this case, was "rm")
Riviera it replaces the {} with the pathnames it found.
Riviera the + says to put many of them
justinko amazing
Riviera with a \; instead of a +, one rm would be started per file
justinko are you a system admin by job?
Riviera but since rm can remove more than one file at a time ... using "+" is more efficient
Riviera no, i'm not :)
Riviera i study humanities ,)
Riviera am sorry, need to leave now, quite late here :)
Riviera nite :)
justinko thank you for the help!
Riviera :)

πŸ™‚

Written by Amber Jain

November 12, 2009 at 5:13 AM

Are you a programmer or a lawyer?

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Before starting, let me tell you that I’m a programmer πŸ™‚

I recently found out Thomas Pfaff’s (#openbsd nick: tp76) website. The home page reads like:

$ wc -l license/ISC license/GPL | head -2
13 ISC
674 GPL

In the end it says: “Are you a programmer or a lawyer?“. I guess I should be tagged ‘programmer’ (I always prefer ISC or BSD license). What about you?

πŸ™‚

Written by Amber Jain

October 26, 2009 at 6:33 PM

[Cross platform + Free] Voice and Video chat programs

with 8 comments

Version: 0.2 (includes update 1)
Changelog: Removed ratings, added other programs to this list (without description).
Last updated: October 18, 2009

Hello,

I formatted my XP installation a few days ago (and I installed Kubuntu 9.04 that dual boots with OpenBSD 4.5). After some time when I wished to use voice chatting services (Free PC to PC voice calls), I found out that most popular voice/video chat services like Yahoo messenger, Google chat etc. were not available/supported by commercial vendors on Linuxes/BSDs/Unixes. 😦 I searched Google and found following voice/video chat program options:


[ Mind you, most services mentioned below are Free and supported on more than one platforms. Moreover, I tested only voice/text chat (and NOT video chat), so the ratings and reviews involve only text/voice chat. ]



1. Ekiga:
Description- Ekiga (formely known as GnomeMeeting) is an open source VoIP and video conferencing application for GNOME. Ekiga uses both the H.323 and SIP protocols. It supports many audio and video codecs, and is interoperable with other SIP compliant software and also with Microsoft NetMeeting. Free Your Speech!

Platforms supported- Atleast Linux/Unix/BSD, probably Mac OS X, Windows XP/Vista.

My views: Works great! I tested only Voice chat. Installed easily. Iirc, no configuration was needed.



2. WengoPhone (now called “Qutecom”):
Description- A single application to talk, chat and share for free with anyone.

Platforms supported- Atleast many versions of Linux, Mac OS X and Windows.

My views: I never installed this. But reviews about WengoPhone on internet point out that it should be easy to install and use.



3. Skype:
Description- Free calls, video calls and instant messaging over the internet.

Platforms supported- Versions exist for Linux, Linux-based Maemo, Mac OS X (Intel and PPC), iPhone OS (iPhone and iPod Touch), Microsoft Windows (2000, XP, Vista, Windows Mobile), and even Sony’s PSP. (Source: Wikipedia)

My views: Works great! I tested only Voice chat. Installed easily. Iirc, no configuration was needed.



4. Jabbin:
Description- Jabbin is an original mashup of Social Network, Instant messaging and VoIP developed entirely on the widely-used and open protocol, Jingle/XMPP, and open source software, including Asterisk, Openfire and Jobill, a billing system.
Jabbin is an Open Source instant messaging program that allows free PC to PC calls using the VoIP system over the Jabber network. The Release 2.0 use the libjingle protocol.

Platforms supported- It appears that this works on atleast recent Windows releases and many Linux/Unix/BSD distributions.

My views: I tried installing it only once and failed. So this may prove to be a useful program but don’t ask my opinion.



5. TokBox:
Description- Free video chat and video mail to anyone in the world without downloads or hassles. Video call your AIM, MSN, GMail and Yahoo buddies. Tokbox is a free service that lets you talk with your friends over live video. Here’s how it works: you sign up and we give you a link. When you want to talk with anyone, just give them the link – they click and you chat. Embeddable on all websites and social networks. No cost. No prepaid minutes. Really free.

Platforms supported- Talk through your browser. No chat client needed. There is no client required. This service from Meebo works from within a modern web browser (e.g. Mozilla Firefox).

My views- In my case, I could neither send nor receive any voice data. It appeared as if everything was working right, but I could not use this service.



That’s it…If I find some other free and useful services, then I will post them here as updates.



UPDATE-1: There are many other programs that are pretty nice to be added to this list. Mind you, I had not used most of these programs myself:
1. Empathy: Empathy is a messaging program which supports text, voice, and video chat and file transfers over many different protocols.
2. Tinychat: The web 2.0 site for making free, disposable chat rooms with live audio and video.
3. Gyachi: GyachE Improved supports almost all of the features found in the official Windows Yahoo! Messenger client: Voice chat, webcams, faders, ‘nicknames’, audibles, avatars, display images, and more. (Source: Wikipedia)
4. Pidgin: As of version 2.6 (released on August 18, 2009) Pidgin has a voice/video framework which uses Farsight2 and is based on Mike Ruprecht’s Google Summer of Code project from 2008. That release provides the ability to have voice/video conversations using the XMPP protocol (including Google Talk), though the implementation is not yet fully complete. The framework will also allow for voice/video conversations on other protocols, such as MSN and Yahoo, in the future (Source: Wikipedia)

Other possible options include Kopete, gaim-vv (many of these programs are limited/reduced support applications).
Another option requires you to install some supported OS for your choice of chat client inside a virtual machine.

Note: I’m not planning to update this article now (unless I find something really amazing) because you can retrieve all such information from Google. If you know of similar programs, post them in comments.

Have fun! πŸ™‚

Written by Amber Jain

August 13, 2009 at 6:22 PM