ajithbh

#!/usr/bin/env python

import argparse
import sys

enabled = []
disabled = []

class MethodWrapper():
    def __init__(self):

ajithbh

#include <fstream>
 
using namespace std;
ofstream logfile;
 
void LogToFile(QtMsgType type, const char *msg) {
  QString datetime = QDateTime::currentDateTime().toString("yyyy.MM.dd hh:mm:ss");
  switch (type) {
    case QtDebugMsg:
      logfile << datetime.toString().toAscii().data() << " [Debug] " << msg << "\n";

ajithbh

while getopts ae:f:h:qs: option
do
  case "${option} in 
    a) AFLAG="TRUE"  ;;
    e) EOPTION=${OPTARG}  ;;
    f) FILE=${OPTARG}  ;;
    q) QUIET="TRUE"  ;;
    s) SERVER=${OPTARG}  ;;
    h|\?) usage && exit 1  ;;
  esac

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void mem_avail(void)
{
  char *cmd = "awk '{ if (NR == 2) { print $4 }}' /proc/meminfo";
  
  FILE *cmdfile = popen(cmd, "r");
  char result[256] = { 0 };
  
  while (fgets(result, sizeof(result), cmdfile) != NULL) {
    printf("%s\n", result);
  }

ajithbh

#include <sys/stat.h>

// 0: No Such Device, 1: Found Device
int has_device(char *path)
{
  struct stat buf;
  
  if (stat(path, &buf) < 0) {
    return 0;
  }

ajithbh

If you forgot "sudo vim" and get error "Can't open file for writing"

:w !sudo tee %

http://stackoverflow.com/questions/2600783/how-does-the-vim-write-with-sudo-trick-work

ajithbh

PPPoE
  provides the ability to connect a network of hosts over a simple bridging access device to a remote access concentrator.
  Each PPP session must learn the ethernet address of the remote per, as well as establish a unique session identifier.
  2 Stages -
    1. Discovery stage
    2. PPP session stage

  Discovery is a client-server relationship
  PPP defines a peer-to-peer relationship

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Point-to-Point Protocol (PPP)

• provides a standard method for transporting multiprotocol datagrams over point-to-point links.
• Comprised of 3 main components
  1. A method for 'encapsulating' multi-protocol datagrams
  2. A Link Control Protocol (LCP) for establishing, configuring and testing the data-link connection
  3. A family of Network Control Protocols (NCPs) for establishing and configuring different network layer protocols

Encapsulation

PPP encapsulation provides for multiplexing of different network-layer protocols simultaneously over the same link. Only 8 additional octets are necessary to form the encapsulation when used within the default framing which is similar to High-level Data Link Control (HDLC) framing.

ajithbh

IPSec framework of open standards define the essentials of network security
  - Data Origin Authentication
  - Data Integrity
  - Data Confidentiality
  - Anti-replay

IPSec provides security based on the negotiated Security Association (SA)

A Security Association Database (SADB) is a repository of SA's, which can be added dynamically by means of Internet Key Exchange (IKE) or manually.