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# ~/.bashrc: executed by bash(1) for non-login shells.
# see /usr/share/doc/bash/examples/startup-files (in the package bash-doc)
# for examples
////
# If not running interactively, don't do anything
[ -z "$PS1" ] && return

# don't put duplicate lines in the history. See bash(1) for more options
export HISTCONTROL=ignoredups
# ... and ignore same sucessive entries.
export HISTCONTROL=ignoreboth

# check the window size after each command and, if necessary,
# update the values of LINES and COLUMNS.
shopt -s checkwinsize

# make less more friendly for non-text input files, see lesspipe(1)
[ -x /usr/bin/lesspipe ] && eval "$(lesspipe)"

# set variable identifying the chroot you work in (used in the prompt below)
if [ -z "$debian_chroot" ] && [ -r /etc/debian_chroot ]; then
    debian_chroot=$(cat /etc/debian_chroot)
fi

# set a fancy prompt (non-color, unless we know we "want" color)
case "$TERM" in
    xterm-color) color_prompt=yes;;
esac

# uncomment for a colored prompt, if the terminal has the capability; turned
# off by default to not distract the user: the focus in a terminal window
# should be on the output of commands, not on the prompt
#force_colored_prompt=yes

if [ -n "$force_color_prompt" ]; then
    if [ -x /usr/bin/tput ] && tput setaf 1 >&/dev/null; then
 # We have color support; assume it's compliant with Ecma-48
 # (ISO/IEC-6429). (Lack of such support is extremely rare, and such
 # a case would tend to support setf rather than setaf.)
 color_prompt=yes
    else
 color_prompt=
    fi
fi

if [ "$color_prompt" = yes ]; then
    PS1='${debian_chroot:+($debian_chroot)}\[\033[01;32m\]\u@\h\[\033[00m\]:\[\033[01;34m\]\w\[\033[00m\]\$ '
else
    PS1='${debian_chroot:+($debian_chroot)}\u@\h:\w\$ '
fi
unset color_prompt force_color_prompt

# If this is an xterm set the title to user@host:dir
case "$TERM" in
xterm*|rxvt*)
    PROMPT_COMMAND='echo -ne "\033]0;${USER}@${HOSTNAME}: ${PWD/$HOME/~}\007"'
    ;;
*)
    ;;
esac

# Alias definitions.
# You may want to put all your additions into a separate file like
# ~/.bash_aliases, instead of adding them here directly.
# See /usr/share/doc/bash-doc/examples in the bash-doc package.

#if [ -f ~/.bash_aliases ]; then
#    . ~/.bash_aliases
#fi

# enable color support of ls and also add handy aliases
if [ "$TERM" != "dumb" ] && [ -x /usr/bin/dircolors ]; then
    eval "`dircolors -b`"
    alias ls='ls --color=auto'
    #alias dir='ls --color=auto --format=vertical'
    #alias vdir='ls --color=auto --format=long'

    #alias grep='grep --color=auto'
    #alias fgrep='fgrep --color=auto'
    #alias egrep='egrep --color=auto'
fi

# some more ls aliases
#alias ll='ls -l'
#alias la='ls -A'
#alias l='ls -CF'

# enable programmable completion features (you don't need to enable
# this, if it's already enabled in /etc/bash.bashrc and /etc/profile
# sources /etc/bash.bashrc).
if [ -f /etc/bash_completion ]; then
    . /etc/bash_completion
fi

# LD_LIBRARY_PATH
  OTCL_LIB=/home/bluebamus/ns/ns-allinone-2.33/otcl-1.13
  NS2_LIB=/home/bluebamus/ns/ns-allinone-2.33/lib
 
#  OTCL_LIB=/home/bluebamus/ns/ns/ns-allinone-2.33/otcl-1.13
#  NS2_LIB=/home/bluebamus/ns/ns/ns-allinone-2.33/lib
 
  X11_LIB=/usr/X11R6/bin
  USR_LOCAL_LIB=/usr/local/lib
  export  LD_LIBRARY_PATH=$LD_LIBRARY_PATH:$OTCL_LIB:$NS2_LIB:$X11_LIB:$USR_LOCAL_LIB

  # TCL_LIBRARY
  TCL_LIB=/home/bluebamus/ns/ns-allinone-2.33/tcl8.4.18/library
  USR_LIB=/usr/lib
  export TCL_LIBRARY=$TCL_LIB:$USR_LIB

#  TCL_LIB=/home/bluebamus/ns/ns/ns-allinone-2.33/tcl8.4.18/library
#  USR_LIB=/usr/lib
#  export TCL_LIBRARY=$TCL_LIB:$USR_LIB

  # PATH
 XGRAPH=/home/bluebamus/ns/ns-allinone-2.33/bin:/home/bluebamus/ns/ns-allinone-2.33/tcl8.4.18/unix:/home/bluebamus/ns/ns-allinone-2.33/tk8.4.18/unix
  NS=/home/bluebamus/ns/ns-allinone-2.33/ns-2.33/
#NS=/home/bluebamus/ns/ns/ns-allinone-2.33/ns-2.33/
  NAM=/home/bluebamus/ns/ns-allinone-2.33/nam-1.13/
#NAM=/home/bluebamus/ns/ns/ns-allinone-2.33/nam-1.13/
  PATH=$PATH:$XGRAPH:$NS:$NAM:$NSP

LD_LIBRARY_PATH=/home/bluebamus/ns/ns-allinone-2.33/otcl-1.13
TCL_LIBRARY=$NS_DIR/tcl8.4.18/library
PATH=$PATH:$NS_DIR/bin:$NS-DIR/ns-2.33/bin:$NS_DIR/ns-2.33:$NS_DIR/tcl8.4.18/unix:$NS_DIR/tk8.4.18/unix

#LD_LIBRARY_PATH=/home/bluebamus/ns/ns/ns-allinone-2.33/otcl-1.13
#TCL_LIBRARY=$NS_DIR/tcl8.4.18/library
#PATH=$PATH:$NS_DIR/bin:$NS-DIR/ns-2.33/bin:$NS_DIR/ns-2.33:$NS_DIR/tcl8.4.18/unix:$NS_DIR/tk8.4.18/unix

#g++
PATH=$PATH:/usr/include/c++/4.2.3:/usr/include/c++/4.2

# deb cdrom:[Ubuntu 8.04 _Hardy Heron_ - Alpha i386 (20080306.1)]/ hardy main restricted
deb-src http://archive.ubuntu.com/ubuntu/ hardy main restricted #Added by software-properties
# See http://help.ubuntu.com/community/UpgradeNotes for how to upgrade to
# newer versions of the distribution.

deb http://archive.ubuntu.com/ubuntu/ hardy main restricted
deb-src http://archive.ubuntu.com/ubuntu/ hardy main multiverse universe #Added by software-properties

## Major bug fix updates produced after the final release of the
## distribution.
deb http://archive.ubuntu.com/ubuntu/ hardy-updates main restricted
deb-src http://archive.ubuntu.com/ubuntu/ hardy-updates restricted main multiverse universe #Added by software-properties

## N.B. software from this repository is ENTIRELY UNSUPPORTED by the Ubuntu
## team, and may not be under a free licence. Please satisfy yourself as to
## your rights to use the software. Also, please note that software in
## universe WILL NOT receive any review or updates from the Ubuntu security
## team.
deb http://archive.ubuntu.com/ubuntu/ hardy universe
deb http://archive.ubuntu.com/ubuntu/ hardy-updates universe

## N.B. software from this repository is ENTIRELY UNSUPPORTED by the Ubuntu
## team, and may not be under a free licence. Please satisfy yourself as to
## your rights to use the software. Also, please note that software in
## multiverse WILL NOT receive any review or updates from the Ubuntu
## security team.
deb http://archive.ubuntu.com/ubuntu/ hardy multiverse
deb http://archive.ubuntu.com/ubuntu/ hardy-updates multiverse

## Uncomment the following two lines to add software from the 'backports'
## repository.
## N.B. software from this repository may not have been tested as
## extensively as that contained in the main release, although it includes
## newer versions of some applications which may provide useful features.
## Also, please note that software in backports WILL NOT receive any review
## or updates from the Ubuntu security team.
# deb http://kr.archive.ubuntu.com/ubuntu/ hardy-backports main restricted universe multiverse
# deb-src http://kr.archive.ubuntu.com/ubuntu/ hardy-backports main restricted universe multiverse

## Uncomment the following two lines to add software from Canonical's
## 'partner' repository. This software is not part of Ubuntu, but is
## offered by Canonical and the respective vendors as a service to Ubuntu
## users.
# deb http://archive.canonical.com/ubuntu hardy partner
# deb-src http://archive.canonical.com/ubuntu hardy partner

deb http://archive.ubuntu.com/ubuntu/ hardy-security main restricted
deb-src http://archive.ubuntu.com/ubuntu/ hardy-security restricted main multiverse universe #Added by software-properties
deb http://archive.ubuntu.com/ubuntu/ hardy-security universe
deb http://archive.ubuntu.com/ubuntu/ hardy-security multiverse
deb http://archive.ubuntu.com/ubuntu/ hardy-proposed restricted main multiverse universe
deb-src http://archive.ubuntu.com/ubuntu/ hardy-proposed restricted main multiverse universe #Added by software-properties

## Pidgin
# deb http://archive.haz3.com/ubuntu gutsy pidgin
deb http://archive.ubuntu.com/ubuntu/ hardy-backports restricted main multiverse universe
deb-src http://archive.ubuntu.com/ubuntu/ hardy-backports restricted main multiverse universe #Added by software-properties

# deb http://ppa.launchpad.net/awn-testing/ubuntu hardy main
# deb-src http://ppa.launchpad.net/awn-testing/ubuntu hardy main

Memory Leaks

• OTcl

  OTcl, especially TclCL, provides a way to allocate new objects, however, it does not accordingly provide a garbage collection mechanism for these allocated objects. This can easily lead to unintentional memory leaks. Important: tools such as dmalloc and purify are unable to detect this kind of memory leaks. For example, consider this simple piece of OTcl script:

  set ns [new Simulator]
  for {set i 0} {$i < 500} {incr i} {
          set a [new RandomVariable/Constant]
  }
  

  One would expect that the memory usage should stay the same after the first RandomVariable is allocated. However, because OTcl does not have garbage collection, when the second RandomVariable is allocated, the previous one is not freed and hence results in memory leak. Unfortunately, there is no easy fix for this, because garbage collection of allocated objects is essentially incompatible with the spirit of Tcl. The only way to fix this now is to always explicitly free every allocated OTcl object in your script, in the same way that you take care of malloc-ed object in C/C++.

• C/C++

  Another source is memory leak is in C/C++. This is much easier to track given tools that are specifically designed for this task, e.g., dmalloc and purify. Ns has a special target ns-pure to build purified ns executable. First make sure that the macro PURIFY in the ns Makefile contains the right -collector for your linker (check purify man page if you don't know what this is). Then simply type make ns-pure. See here on how to use ns with libdmalloc.

Tcl-level Debugging

The command $ns gen-map lists all objects in a raw form.

This is useful to correlate the position and function of an object given its name. The name of the object is the OTcl handle, usually of the form ``_o###''. For TclObjects, this is also available in a C++ debugger such as gdb as this->name_.

C-Level Debugging

The following macro for gdb makes it easier to see what happens in subroutines that take Tcl arguments (like TcpAgent::command()):

## for dumping Tcl-passed arguments
define pargvc
set $i=0
while $i < argc
  p argv[$i]
  set $i=$i+1
  end
end
document pargvc
Print out argc argv[i]'s common in Tcl code.
(presumes that argc and argv are defined)
end

Mixing Tcl and C debugging

(Always a fun concept, right?)

1. The following incantation (shown in bold below) gets you access to the Tcl debugger. Notes on how you can then use this debugger and what you can do with it are documented elsewhere.

   (gdb) run
   Starting program: /nfs/prot/kannan/PhD/simulators/ns/ns-2/ns 
   ...
   
   Breakpoint 1, AddressClassifier::AddressClassifier (this=0x12fbd8)
       at classifier-addr.cc:47
   (gdb) p this->name_
   $1 = 0x2711e8 "_o73"
   (gdb) call Tcl::instance().eval("debug 1")
   15: lappend auto_path $dbg_library
   dbg15.3> w
   *0: application
    15: lappend auto_path /usr/local/lib/dbg
   dbg15.4> Simulator info instances
   _o1
   dbg15.5> _o1 now
   0
   dbg15.6> # and other fun stuff
   dbg15.7> _o73 info class
   Classifier/Addr
   dbg15.8> _o73 info vars
   slots_ shift_ off_ip_ offset_ off_flags_ mask_ off_cmn_
   dbg15.9> c
   (gdb) w
   Ambiguous command "w": while, whatis, where, watch.
   (gdb) where
   #0  AddressClassifier::AddressClassifier (this=0x12fbd8)
       at classifier-addr.cc:47
   #1  0x5c68 in AddressClassifierClass::create (this=0x10d6c8, argc=4, 
       argv=0xefffcdc0) at classifier-addr.cc:63
   ...
   (gdb)

2. In a like manner, if you have started ns through gdb, then you can always get gdb's attention by sending an interrupt, usually ^C on berkeloidrones.

The first thing to do if you run out of memory is to make sure you can use all the memory on your system. Some systems by default limit the memory available for individual programs to something less than all available memory. To relax this, use the limit or ulimit command These are shell functions---see the manual page for your shell for details. Limit is for csh, ulimit is for sh/bash.

Simulations of large networks can consume a lot of memory. Ns-2.0b17 supports Gray Watson's dmalloc library (see its web documentation and source code). To add it, install it on your system or leave its source in a directory parallel to ns-2 and specify --with-dmalloc when configuring ns. Then build all components of ns for which you want memory information with debugging symbols (this should include at least ns-2, possibly tclcl and otcl, maybe also tcl).

To use dmalloc:

1. define an alias (csh: alias dmalloc 'eval `\dmalloc -C \!*`', bash: function dmalloc { eval `command dmalloc -b $*` })
2. Turn debugging on by typing dmalloc -l logfile low
3. Run your program (which was configured and built with dmalloc as described above)
4. Interpret logfile by running dmalloc_summarize ns <logfile (You need to download dmalloc_summarize separately.)

On some platforms you may need to link things statically to get dmalloc to work. On Solaris this is done with by linking with these options: "-Xlinker -B -Xlinker -static {libraries} -Xlinker -B -Xlinker -dynamic -ldl -lX11 -lXext". (You'll need to change Makefile. Thanks to Haobo Yu and Doug Smith for workign this out.)

We can interpret a sample summary produced from this process on ns-2/tcl/ex/newmcast/cmcast-100.tcl with an exit statement after the 200'th duplex-link-of-interefaces statement:

• Ns allocates ~6MB of memory.
• ~1MB is due to TclObject::bind
• ~900KB is StringCreate, all in 32-byte chunks
• ~700KB is NewVar, mostly in 24-byte chunks

Dmalloc_summarize must map function names to and from their addresses. It often can't resolve addresses for shared libraries, so if you see lots of memory allocated by things beginning with ``ra='', that's what it is. The best way to avoid this problem is to build ns statically (if not all, then as much as possible).

Dmalloc's memory allocation scheme is somewhat expensive, plus there's bookkeeping costs. Programs linked against dmalloc will consume more memory than against most standard mallocs.

Dmalloc can also diagnose other memory errors (duplicate frees, buffer overruns, etc.). See its documentation for details.

Memory Conservation Tips

If you have many links or nodes:

avoid trace-all

$ns trace-all $f causes trace objects to be pushed on all links. If you only want to trace one link, there's no need for this overhead. Saving is about 14 KB/link.

use arrays for sequences of variables

Each variable, say n$i in set n$i [$ns node], has a certain overhead. If a sequence of nodes are created as an array, i.e. n($i), then only one variable is created, consuming much less memory. Saving is about 40+ Byte/variable.

avoid unnecessary variables

If an object will not be referred to later on, avoid naming the object. E.g. set cmcast(1) [new CtrMcast $ns $n(1) $ctrmcastcomp [list 1 1]] would be better if replaced by new CtrMcast $ns $n(1) $ctrmcastcomp [list 1 1]. Saving is about 80 Byte/variable.

run on top of FreeBSD

malloc() overhead on FreeBSD is less than on some other systems. We will eventually port that allocator to other platofrms.

dynamic binding (NEW)

Using bind() in C++ consumes memory for each object you create. This approach can be very expensive if you create many identical objects. Changing bind()'s to delay_bind() changes this memory requirement to per-class. See ~ns/object.cc for an example of how to do binding, either way.

1. 준비

korean-amitasia-44eb.awl

 - USB 드라이버를 꼽으세요.

 - 자동실행이 나오면 취소를 누르세요.

 - 이 작업 도중엔 절대로 C: 건 D:건 들어가시면 안됩니다.

 - 필요 프로그램

    : V3 NEO 최신버젼 : www.ahnlab.com

    : ad-aware 최신버젼 : 알아서 받아주세요... 죄송. (ad-aware 한글패치 다운로드 )

    : trojankiller : 파일 첨부 해놓았습니다.

팝업 윈도우가 뜨면 꼭 취소를 누르셔야합니다. 확인을 누를시 autorun.inf 파일이 자동실행되어 바이러스가 전염됩니다.

2. 현재 구동중인 바이러스 목록 체크

 - 자 일단 Ctrl + Alt + Del 키를 눌러 작업관리자 창을 여세요.

 - 응용 프로그램 탭에 현재 실행되고있지 않은 이상한 프로그램이 떠있다면 과감하게 작업끝내기를 누르세요.

 - 프로세스 탭에 "SocksA" "algsrv" "taso" "kavo" "FileKan" "EL" 등의 프로세스가 실행되고 있다면 해당 프로세스를 과감하게 끝내버리세요.

어제인가 뉴스에 바레인의 국왕과 왕족들의 횡포를 여러 인터넷 툴 특히 Google Earth를 통해 알고는 시민들이 항의하는 것이 나왔었죠.

참조: http://news.naver.com/news/read.php?mode=LSD&office_id=052&article_id=0000135000&section_id=115&menu_id=115

그런 의미에서 오늘 발표된 캐나다의 토론토 대학의 한 소프트웨어를 소개시켜 드릴까 합니다.

일단 제 글은

1. 토론토 대학의 페이지:

http://www.news.utoronto.ca/bin6/061128-2766.asp

2. 컴퓨터 잡지의 기사:

http://www.computing.co.uk/vnunet/news/2169789/boffins-beat-web-censors

3. Psiphon 프로그램 홈페이지

http://psiphon.civisec.org/

를 참조한 내용입니다.

서비스 시기: 12월 1일

소프트웨어 명칭: Psiphon

소프트웨어 목적: 인터넷 감시가 심각한 40여개국의 인터넷 유저가 국가 인터넷 감시망을 피해 세계 인터넷에 자유롭게 접속할 수 있도록 도와주는 소프트웨어

이 프로그램은 뉴스에 난 바레인 또는 북한 같은 실정의 40여개 국에서 인터넷 censorship (감시) 를 통해 특정 정치사이트를 접근하지 못하게 하는 경우에 그 감시를 피하도록 도와주는 소프트웨어입니다.

다른 경우라면 해킹이라 여기겠지만 이곳에서 정한 40여개 국의 경우 인터넷을 통해 인권신장을 일궈보자는 토론토의 인권주의자 교수님의 의지가 담겨 있죠.

원리는 이 소프트웨어를 저희나라나 미국처럼 자유롭게 인터넷에 접속할 수 있는 곳에서 실행할 경우 실행하시는 분의 컴퓨터가 서버가 되어 인터넷 감시가 삼엄한 이 40여개 국의 친구나 가족들에게 인터넷 어드레스를 보냅니다.

그러면 그 어드레스를 받은 감시당하는 국가의 친척이나 친구들이 소프트웨어를 실행한 컴퓨터를 통해 인터넷을 자유롭게 돌아다닐 수 있는 것이죠.

내용이 암호화 되므로 감시국가들의 감시프로그램들이 작동을 못할 것이고, 인터넷 접속권리를 되찾아 인터넷 언론의 자유를 얻게 되는 것이죠.

실질적으로 인터넷기술을 이용한 인권운동으로 앞으로 세계인권성장에 도움이 되길 빕니다.

참고로 여러 억압받는 나라의 인터넷 이용을 돕고자 하는 분은 위의 사이트에 가셔서 한번 살펴보세요. 당장은 버그가 있을지도 모르니 실행하는것을 추천해 드리지는 못하지만 몇개월 지나 안정적인 서비스가 가능해지면 인터넷 회선속도가 빠른 저희나라 사람도 작은 힘이나마 보탤수 있을 것 같네요 :)