======Systems Programming Journal======
====MONTH Day, YEAR====

This is a sample format for a dated entry. Please substitute the actual date for "Month Day, Year", and duplicate the level 4 heading to make additional entries.

As an aid, feel free to use the following questions to help you generate content for your entries:

  * What action or concept of significance, as related to the course, did you experience on this date?
  * Why was this significant?
  * What concepts are you dealing with that may not make perfect sense?
  * What challenges are you facing with respect to the course?

====January 26, 2016====

? : compressed if statement o
Getopt; cat;
-n --number : line numbers
-E --show-ends
--help
--version

====January 28, 2016====

who: checking records of login
     how long?
utmp: login records
short: short int
posix(widely spread)
getutent -access utmp file entries 
reads a line from the current file position in utmp file.

====Febuary 2, 2016====

mytime -> tm_mon : month
mytime -> tm_mday : day
mytime -> tm_hour : hour

*strcpy: in string.h library
 copy a string

stat - get file status
mode_t st_mode; <<protection


====Febuary 4, 2016====

idle time: last time access the file

ls: opendir, closedir, readdir, scandir, ...

====Febuary 9, 2016====

implementing ls -l: file permission,,who owns it(usrid),,date,name
stat struct st_nlink
stating file name : looking for the directory

====Febuary 11, 2016====

blocksize stat -> st_size
ls -> mtime: modify time
mytime -> tm_mon; etc. 

====Febuary 23, 2016====

new projectv _primenumber algorithm

I finally submit chmode. It was surprising that the actual chmod part was just a line.\\
chmod( filename, permission );

====Febuary 25, 2016====

man 2 fork : create a child process (doesn't inherits the timer from parents)\\
wait -wait for process to change state\\
getpid -get process id

====March 1, 2016====

pnc1: using fork and child process

====March 3, 2016====

threading -> multi-threading\\
pthreads(7): parent's process id is different than child process id. 
thread & child process: each child have thread\\
forking & threading : space & time\\
data hazard: synchronization\\
pthread_create - create a new thread\\
 
====March 8, 2016====

make file and load into array and print out the value
read from the file.\\
sorting

====March 10, 2016====

sockets\\
* protocol\\
* everyone have to speak same language\\
* using TCP\\
* write server first\\
port80 : https\\

====March 15, 2016====

bzero -write zero-valued bytes(calloc)
tcp : instant client(telnet netcat)

====March 16, 2016====

Object Oriented Programming\\
PIE: Polymorphism, Inheritance, Encapsulation\\

Procedural, Functional, Logical

====March 17, 2016====

getifaddrs - get interface address (passes double pointer)

====March 22, 2016====

network communication\\
write system call\\
create socket and connect -> connection\\
exec1 - executes a file ( system call )\\

====March 24, 2016====

stty: change and print terminal line settings\\
stty -echo \\
tty_ioctl: ioctls for terminals and serial lines\\

====April 5, 2016====

pipe, pipe2 : create pipe\\
created using mkfifo

====April 7, 2016====

signals!!
signal(2)
kill -l : list available signals
signal 7

====April 12, 2016====

POSIX shared memory\\
shmat: system V shared memory operations\\
shm_open: open 

====April 21, 2016====

ncurses -CRT screen handling and optimization
initscr - initialize screen 

====April 26, 2016====

newwin: creates a pointer to a windowwith given number of lines and columns.\\
subwin: shares memory with original window\\
mvprintw: display at specific position