$Avinash Dubey$

RHEL5 FEDORA — yum install giving Nothing to do

Avinash Dubey — Fri, 18 Mar 2011 16:15:31 +0000

Problem:
yum install was not working
whenever i was trying to install some s/w using yum, it used to check local repository and ended up saying Nothing to do

Solution:
Actually whenever we install some s/w or package using yum , it looks into cd /etc/yum.repos.d/*.repo files
there you would see many different sections under heading
[heading]
baseurl=http://

yum looks for the package under these mentioned repositories i.e. baseurls

just add one more section with this heading to make it look for open source pkgs under fedora repository (works both for rhel5 and fedora)

example.. this worked for me

i wasn’t able to install pkgs like perl,perl-WWW::Mechanize, yumex etc

avidubey@avidubey] cd /etc/yum.repos.d /etc
avidubey@avidubey] ls /etc/yum.repos.d
already-present.repo MyOwn.repo
avidubey@avidubey] cat MyOwn.repo /etc/yum.repos.d
[MySection]
name=MyOwnRepo
baseurl=http://download.fedora.redhat.com/pub/archive/fedora/linux/updates/7/i386/
enabled=1
gpgcheck=0

Eclipse — workspace in use or cannot be created error

Avinash Dubey — Sun, 06 Mar 2011 07:40:52 +0000

Scenario..
I had opened a workspace using eclipse on my linux machine. Now when I was trying to open the same workspace using my laptop through remote connection I was getting a message like “Workspace in use or cannot be created”.

Solution:
whenever you open a workspace using eclipse a .lock file is created that locks the workspace so as to disallow opening the same workspace by someone else.
I just deleted that .lock file and the problem was solved.

Path of .lock file…
the path is
/workspace/package_directory/.metadata/.lock

javascript hashmap

Avinash Dubey — Thu, 10 Feb 2011 15:01:45 +0000

Q. Define and iterate hashmap in javascript

–
//declaration
var myHashmap = {}

//add elements
myHashmap['one'] = “two”;
myHashmap.one = “two”;

//iteration
for(key in myHashmap){
alert(“key is “+ key + ” and element is ” + myHashmap[key]);
}

kill a process if already running

Avinash Dubey — Mon, 08 Nov 2010 13:53:06 +0000

process_id=`ps -e | grep firefox | cut -f1 -d’ ‘`
#check if process exists
if [ "$process_id" != "" ]
then
kill $process_id
fi

dig command to know hostname

Avinash Dubey — Thu, 17 Jun 2010 06:58:27 +0000

dig +short hostname (to get ip address of hostname)
dig +short -x ip-address (for reverse dns ..ie to get hostname from ip address)

cannot display this video mode problem

Avinash Dubey — Fri, 04 Jun 2010 12:46:09 +0000

to login press [ctrl] + F(1-6)
a console promt will come and you can login using your user id and password
then open file /etc/X11/xorg.conf

edit / add line Modes “1280×1024″ i.e.(axb) where a and b is the screen resolution your monitor supports
the file will look somethin like this
Section “Screen”
Identifier “Screen0″
Device “Videocard0″
Monitor “Monitor0″
DefaultDepth 24
SubSection “Display”
Viewport 0 0
Depth 16
Modes “800×600″ “640×480″
EndSubSection
SubSection “Display”
Viewport 0 0
Depth 24
Modes “1024×768″ #changed from “1280×1024″
EndSubSection
EndSection

port 80 problem of apache due to selinux..

Avinash Dubey — Wed, 03 Feb 2010 14:10:18 +0000

problem :

i was having problem with my apache web server….
when i was typing http://localhost apache test page was opening
when i was typing http://172.31.80.205:80 apache test page was opening
when i was typing http://172.31.80.205 …it was giving me error // bad request …
do this to solve te problem…
solution:
first selinux was disabled but no use..so did this and the problem was solved…
kwrite /etc/httpd/modsecurity.d/modsecurity_crs_21_protocol_anomalies.conf
type this and search line containing numeric type of thing…
just comment that line and the problem will be solved…

problem :

Solution:

do this to solve te problem…first selinux was disabled but no use..so did this and the problem was solved…

kwrite /etc/httpd/modsecurity.d/modsecurity_crs_21_protocol_anomalies.conf
type this and search line containing numeric type of thing…just comment that line and the problem will be solved…

reverse linked list using recursion..

Avinash Dubey — Wed, 03 Feb 2010 14:08:12 +0000

node* Reverse(node* ptr)

{

if(ptr->next == NULL)

{

Head = ptr;

return ptr;

}

Reverse(ptr->next)->next = ptr;

return ptr;

}

node* Reverse(node* ptr){if(ptr->next == NULL){Head = ptr;return ptr;}
Reverse(ptr->next)->next = ptr;
return ptr;}

Efficient code for counting set bits…

Avinash Dubey — Sat, 23 Jan 2010 04:25:34 +0000

This is the very efficient code for counting set bits.

int NumberOfSetBits(int i)
{
i = i – ((i >> 1) & 0×55555555);
i = (i & 0×33333333) + ((i >> 2) & 0×33333333);
return ((i + (i >> 4) & 0xF0F0F0F) * 0×1010101) >> 24;
}

Explanation

The first statement partitions i into 2-bit groups and replaces each 2
bit group with the number of 1-bits set in that group. The second
statement partitions the number into 4-bit groups and adds together
the two 2-bit groups in each to get the number of 1-bits originally
set in that 4-bit group. The last statement partitions the number into
8-bit groups and adds the two 4-bit groups in each to get the number
of 1-bits in the 8-bit group. Then the multiplication adds the 8-bit
groups, leaving the sum in the upper 8 bits of the number. The shift
right-justifies the sum in the word.

Faizan n me @ first day in college…

Avinash Dubey — Sun, 20 Dec 2009 17:23:58 +0000

it was my first day of college, room no 2 , Tagore hostel. i was busy chatting with irfan when a very lean and thin guy having an equally lean and thin moustache entered the room along with his father. We both stood up to welcome him and after a very short formal introduction when i thought that its the right time to start our normal informal boys talks this guy started talking like gradpa. His branch was production at that time, so the main topic of his talks was “production is at par with mechanical the only difference being in the name…” and “–do–” and “–do–”…. bole to sirf production ki badai aur kuch ni…uff ….o bhai isne do teen din tak itna pakaya na production ko leke ki kya bataun…

Bbut we were lucky enough that this ordeal ended soon as he finally managed to change his branch to Electrical after a few days.. bas phir kya tha…then he saw the real dubey … itni mari iski pure wing mein ki poocho mat… but i was really happy to see that he never took ma words to heart …. n because of these things only we came quite close to each other…

he was my partner in crime and stayed so till third year…. ek baar to fansa bhi hai achcha khasa meri wajah se…. iam damn sure he can never forget that NIGHT… the most special night in our batch’s history…

the most funny game we used to play was “Hansi — Hansi”…. i donno how come this thing started but this is the main reason which changed the Mr padhaku and sincy faizan into the one f the most bhasad guys of our college.. i still remember during first few weeks of college he used to study separately on his neat n clean table that too under a table lamp… haha guys used to come in our room askin Mr faizan for his notes… but once dat game started wowo… we all saw a new avatar of faizan which never turned back into original one…we used to sit together and laugh continuously unnecessarily for hours till our stomach gave up due to pain… and the irony is that anyone who dared to ask us y we were laughing , after sometime he too used to become the part f dat chain….