raja-ashok

#!/bin/bash

openssl ecparam -genkey -name prime256v1 -conv_form uncompressed -outform PEM -out ec.pem
openssl req -newkey ec:ec.pem -passout pass:123456 -sha256 -subj "/C=IN/ST=Kar/L=En/O=ABC/OU=ABCDepart/CN=root/emailaddress=root@abc.com" -keyout rootkey.pem -out rootreq.pem -config openssl.cnf
openssl x509 -req -in rootreq.pem -passin pass:123456 -sha256 -extfile openssl.cnf -days 14600 -extensions v3_ca -signkey rootkey.pem -out rootcert.pem 

openssl ecparam -genkey -name prime256v1 -conv_form uncompressed -outform PEM -out ec.pem
openssl req -newkey ec:ec.pem -passout pass:123456 -sha256 -subj "/C=IN/ST=Kar/L=En/O=ABC/OU=ABCDepart/CN=server/emailaddress=server@abc.com" -keyout serverkey.pem -out serverreq.pem -config openssl.cnf
openssl x509 -req -in serverreq.pem -passin pass:123456 -sha256 -extfile openssl.cnf -days 14600 -extensions usr_cert -CA rootcert.pem -CAkey rootkey.pem -CAcreateserial -out servercert.pem

raja-ashok

#!/usr/bin/env python

from itertools import groupby

myList = [1, 2, 1, 3, 1]
for x, y in groupby(sorted(myList)):
    # groupby groups by consecutive elements which are similar
    # x is the element, y is the list which contains the elements occurence
    dup_list = list(y)
    print 'x : ' + str(x) + ', y: ' + str(list(dup_list))

raja-ashok

#!/usr/bin/env python

import subprocess
import os

# 1) Calling an external command in Python
# Simple way to call external command is using os.system(...). And this funciton returns the exit value of the command. 
# But the drawback is we wont get stdout and stderr.
ret = os.system('some_cmd.sh')
if ret != 0 :

raja-ashok

tc qdisc add dev <interface_name> root netem delay 120ms

tc qdisc delete dev <interface_name> root netem 

tc qdisc add dev <interface_name> root netem loss 2%

raja-ashok

#!/bin/bash

CSCOPE_DIR="$PWD/cscope"

echo_usage()
{
    echo "Usage: $0 gen|reset [folder]"
    exit -1
}

raja-ashok

parse_git_branch() {
    git branch 2> /dev/null | sed -e '/^[^*]/d' -e 's/* \(.*\)/ (\1)/'
}
netns_name() {
    str=`ip netns identify $$`
    [[ "$str" != "" ]] && echo "\033[1;35m[$str]\033[0m " && return
}
export PS1="\u@\h\[\033[32m\]\w\[\033[33m\]\$(parse_git_branch)\[\033[00m\]\n$ "
eval $(ssh-agent -s)

raja-ashok

for loop

count=5
for i in $(seq $count); do
  echo $i
done

raja-ashok

1) Git SSH configuation
Generate RSA key pair
  - ssh-keygen -t rsa -b 4096 -C "your_email@domain.com"
  - This generates 2 file, id_rsa and id_rsa.pub in ~/.ssh directory.
  - Copy the content of id_rsa.pub and configure in the git settings under the account details.

Then after opening terminal, always execute below 2 command to load the RSA private key (id_rsa).
After loading, all git commands can be executed without entering credentials every time.
   - eval $(ssh-agent -s)
   - ssh-add ~/.ssh/id_rsa

raja-ashok

grep -E "colou?r" * -R
  - Matches both "colour" and "color"

raja-ashok

To Setup
  sudo apt install hplip
  sudo hp-setup -i

To scan and get soft copy
  hp-scan