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======C/C++ 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 25, 2015====

Most part that I had to do for the project CCI0 was already done ahead since I had to do it for UNIX project.  However, it was first time making a program using C by myself. Making a program is always a fun thing to do. I reviewed what I learned in the class especially all the terms that was used in the "Hello, World!" program.  Because I don't know most of the command that is used in Terminal or PUTTY, it was little bit challenging for me using those. I am pretty sure that there is a command for "copy". However, I almost write whole thing all over again and I realized that I don't have to do that. In my lab 46 account, there are files and folders all over the place because I don't know how to erase them. I think I should clean some files up before it gets really messy. 

====January 31, 2015====

For the project mms0, I had to make a program that gives me an answer for the square two digit number ending with 5. Since there were not much explanation about how to make a program, I had to do it by myself. I start programming by applying the multiplication program that we did in class. It was very challenging. However, I had so much fun, especially, figuring out how to make fscanf and fprintf work. Now, I know the concept of %d and how to apply in a program. It was easy to understand: %d equals to a number that we define on the next to following comma. Also, it seems like I can use as many %d as I want. :-D
Because I found out the answer to the every problem that I had on the book, I don't have any problem.

====Febuary 7, 2015====

First of all, project mbe0 was extremely hard!! 8-o I kept trying and got errors every time. The first challenge was how to separate number into digits. I tried by myself and eventually it got so long and messy. So I got help from the internet and it gave me how to get the digits separate. After that, I got stuck on adding digits. It wasn't hard but confusing. But I draw a number tree on a paper, and it helped me make a program. I learned how to use if else statement and logic that is related to math. For now, my program can't handle it. However, I know how to make it. For any digit numbers, I just have to make more "add" variable and make more branches. I totally see the pattern. ... OMG.. is.. is it the next project? .... oh... I think I can do it but it gives me so much headache.

====February 24, 2015====

The project for last week was mbe1 which is similar to the mbe0. However, I used the loop and array to make it work for the 2 to 8 digits. Actually, I wrote the code that works to 10 digits using for loop. I put each digit to the digit array backwards. Therefore, the result array had the result backwards. Everything worked fine till then. However, at last, I did not know how to merge array to the 1 number. So I just used n*11 for the answer which worked fine. But it is still mystery. I learned it is important to initializing every value, otherwise, the value get the randomized number. Also, for the rounding number part, I just used if statement (which is not really good way I think). If the number before was more than 9 than just add 1 to the next number. Something like that. It took me long time to write mbe1 code. However, it was worth it.8-)

====March 6, 2015====

I had a lot of problem making function work. So I wasn't able to submit the project afn0. However, generous Matt gave the class good hint of how to make a function using char * with array. It was very confusing at first. Still working on it. I learned "char array[];" can be also written as "char *array;" It is functionally the same. However, in the function, it is better to use without square bracket. Also, another interesting thing was *(array+n), which can be written as array[n]; Cool!
It solved my problem of how to return array in a function. Because one question that I had was that I couldn't write "return(array[n]);" He just totally solved my problem. Only thing that I had to write was "return(array);" Awesome. I also learned debugging with gcc called gdb, I guess. It seemed very helpful although I did not try by myself yet. 

====March 8, 2015====

I figured out the 19 digit problem. It was problem of whether signed or unsigned. After I fix my code
unsigned long int n;
fscanf( stdout, "%lu", n );
It worked up to 20 digits. I was so happy. However, I bumped into another problem that the calculation went wrong whenever the input value ends with zero or zeros. I kind of felt bad. But other than that, I think I did pretty well since it took me for 2 weeks to finish this project. Awesome. If I have time, I want to write a perfect code for this project that gives the right value even though it ends with 0. 

====April 7, 2015====

I didn't even look at the project because I was super busy with other classes. So I looked up the project today and finished today. cbf0 project wasn't that long. However, I encountered new functions that is related to making files, reading files and writing files. It was fopen, fclose, fput, and fseek. I was able to change the position for fscan by using fseek function. SEEK_END allowed me to read from the end of the file. So my code opened two files( input, output ) and read input file 12byte from the end using fseek and fscan. I make sure to put into an array. Then, I used fput to put the array to the output file. It was nice project to practice handling files. Now, I think I can read and write any file. So confident.

======UNIX/Linux Fundamentals 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 22, 2015====

As I was working on the project UXI0I, I learned a lot. For example, I learned how to edit my opus and how to customize it. Honestly, Lab46 and wiki was quite interesting. I got my lab46 email and activate it. Also, I used lab46 mercurial repository for the first time! (I add commit and push to repository) At the point of finishing the lab, I got familiar logging in to the system and using terminal (prompt) for the lab46. However, I got confused when I tried to get RIC thing which was all about class chat and the channel and stuff. I eventually got connected to the server but I did not know when to use it and how to use it. This was the biggest challenge of UXI0I. Although it is only beginning of the class, I enjoyed learning about UNIX and Linux.

====January 31, 2015====

The second project, arc0, was quite challenging to me in general; because I had to read a lot about the new words related to archive and file compression and I don't like reading. Moving and copying files were easy, however, it took a while to actually extracting file. The fact that .xz is a type of compressed file was interesting. Also, figuring out the shape of the scrambled files was fun. I didn't know that there was a specific shape, however, I eventually find out as I was playing with tac and rev. I noticed that, for learning computer, playing with things can improve my skill. As I was working through the project, I had a problem. I stuck on STDIO redirection (>). Whenever I use it, it didn't work. So I just copy and paste the text in order to make an result.txt . It was a fun project! HORSEEE =)

====February 11, 2015====

I finished my first puzzlebox and it was very hard for me to finish it. I learned about the command name file which shows me what type of file it is. It was really useful figuring out the puzzlebox. I look up the type of the file named riddle.html and it said that it was originally shiny.tar so I decompressed it and I got the file named making.waves which was uuencoded so using uudecode I found out the file that is zipfile. So I unzip it. The whole process was similar. Looking for the file type and do something to make it readable. nice!
Finally, I was able to get to the result.txt. It was a hard project but learned a lot about the extension of the file and the file type.

====February 12, 2015====

The second puzzle box, pbx1, was easier than the last one since this was my second time solving a puzzle box. I basically did the same thing, however, I learned chmod command which is for authority to get access. I learned 700 is highest. Also, after I got the file, I had to convert the hex code to ascii code. I was trying to use the octal to ascii program, however, I had no chance to use it since the code was hex. So I figure it out by using converter from google.  Then I made the file in order to get the bat ascii art. Because I couldn't change the order of the line I edited with nano. In this lab, chmod was the new thing that I used in the lab.

====March 04, 2015====

It was hard project. Not even close to getting png file. Working on dd command. 
if= file name of= output file skip= offset count= length. if is an option of reading file and of is an option of the output of the file. skip is a command of where to read file. count is an option of how many block size would dd command will read. bs stands for block size. I used dd to separate file to part1 part2 part3 and toc.
some code was encoded so I had to decode it. And I got the rle file so I had to use some special command which is called rletopnm which converts rle file into pnm. So I got the pgm file. Still stuck here and I have to expand the file to x2. 

====March 14, 2015====

Udr1, fun project. I guess I have to get gizmo before even starting the main part of the project. Thankfully, I got the two files that I am supposed to get. I got these files by using dd. [dd if=data.file of=result bs=1 skip=5552] So one file was some ascii art that is 203 byte and other file is reverse data of gizmo according to the instruction. However, I got stuck getting the second file reversed. The instruction said that I have to make a shell scripting. It's been a while writing script. So I asked for some help. I hope this work out nice. I just read the alpine and got the data.file-turbo and I think I have to work on numbers again.. 

====March 17, 2015====

For udr1, I used dd command most of the time. First, I separated a file into 2 files using
dd if of bs count skip. For the first file I used ctrl+c to find the last character of the string. Then skip everything using dd and get the second file. Then, I made a script that saves the last of the string file into the temp file and append each character into one file called gizmo. It took a while to get the complete file(like 3 hours for my laptop). Now I am starting the real part of udr1. I got some questions wrong, but, don't know the result of getting wrong. I saw the project called udr2 last morning,ah..... Can't wait till I  start the project! I am happy hahahahah.. When will the udr project will end?

====April 11, 2015====

Udr2 took long time to finish. The task was analyzing packet from the 6 sessions. The key was to find out what information each packet has. Also, find the specific packet using bgrep. Bgrep tells me the hex address of the specific packet that I am looking for. Another interesting thing was the unix time. There was a command for converting time to unix time(date) and timestamp packet contains the unix time encoded with hex. However, the time recorded as a name of the file doesn't seems like matching the time actually recorded. Because I used hex editor so many times, I find out how to find specific hex character. For example, if I want to find 8A, I can use \8A in the command line of the editor. To find the next matching, I can use '/' and before matching is '?'. I learned a lot through this project since it took me long time to finish it 8-)
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