Notes

Jan 24, 2012 --------- OS

ssh [virtual machine ip address]

(not sure if installed ssh server so ->) sudo apt-get install open ssh

sudo apt-get install manpages-dev

sudo apt-get install linux-source

new screen -> control a c (?)

switch screen -> control a n

man screen

screen

ps axjf process tree

forth # gives pid

second to last on right is user id (who initiated process)

processes just create children

children run binary of process

first binary in memory is init binary, run in user space (always run as root)

child inherits privileges of parent

sudo su - 

gives root@ubuntu:~#

login binary is child of init

ps -el | grep init

exit 

exits root

daemon = process that runs in background

sshd = ssh daemon

etsy

UID

effected UID

real UID

once root priv gone, use SUID bit or use child of root 

man strace

gdb uses ptrace 

clone does work for strace

"free bsd jails"

strace -p pid -o /tmp/my.strace -ff 

ls -la | sort

man 2 pipe gives you pg 2 of manual (system calls)

less my.strace……?

pipe values should correspond to underlying system call

ls -l /proc/PID/maps

sudo ls -l /proc/sys/net/ipv4/tcp_syncookies

proc is a way of looking inside kernel w/o being kernel 

file /bin/bash

man nm -lists symbols from object files

stripped means debug info stripped out

linker and loader

.data 

.heap 

.stack

.tex -- executable goes

one virtual space for one process

why oxc000000 does kernel start there?

pipe and clone

Reaing - chapters 1 & 2 of bovey and suzadi 

how x86 helps linux manage process

http://en.wikipedia.org/wiki/Less_(Unix)