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--- blog:spring2016:kdarling:journal [2016/01/18 21:05] – external edit 127.0.0.1
+++ blog:spring2016:kdarling:journal [2016/03/17 15:22] (current) – [January-Feb, ALL, 2016] kdarling
@@ Line 1: / Line 1: @@
 ======Systems Programming Journal======
-====MONTH Day, YEAR====
+====January-Feb, ALL, 2016====
-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.
+For the entire month of January, we covered the idea of using the manual pages efficiently by using more includes and understanding the unistd.h include.
-As an aid, feel free to use the following questions to help you generate content for your entries:
+Other cool new features that we have learned by using the Linux Manual pages on C and other cool C functions was the stat struct and I believe the group struct.
-  * What action or concept of significance, as related to the course, did you experience on this date?
+The stat struct contains many useful functions such as it helped in the chmod project in setting file permissions.
-  * Why was this significant?
+In order to setup the stat struct and obtain all it's members, an allocation must take place in order for it to properly work. To do so simply state,
-  * What concepts are you dealing with that may not make perfect sense?
-  * What challenges are you facing with respect to the course?
+struct stat *name = (struct stat*) malloc(sizeof(struct stat));
+WALLA! You have obtained all of stat's secret's including the st_mode which helps set file permissions, for example
+name -> st_mode = 0777;
+int chmod(FILE_NAME(I used argv[1], name -> st_mode);
+BAM! Permissions have been set.
+Inside group it gets a little... Strange.
+Using name's st_gid, we can set that to groups, another struct so malloc up bois.
+groups = getgrgid(name -> st_gid); Then now you have access to usernames and unsecured passwords that someone hasn't taken care of, scary stuff.
+Overall we have covered
+cat.c
+ls.c
+who.c
+and our very own chmod.c for those who did it and attempted it. Other cool features will be listed later inside the blog.
+====March, 2016====
+Currently in March, we have playing more with primes and utilizing primefork, primethread, and currently we are playing with different types of network interfaces.
+PrimeFork.c
+Contain(s)
+Primebrutefork.c
+Primesqrtfork.c
+Primebrute utilizes our brute force method of accessing each individual number from 2 to the max number specified for that range.
+Primesqrt utilizes our square root approach and lowers the number it has to search for in order to determine if it's prime.
+The fork uses a process of quite literally multiplying the program itself but then the program has a check statement to make sure that the program multiplied is either the true parent or a child/forked process.
+PrimeThread
+Contain(s)
+Primebrutethread.c
+Primesqrtthread.c
+Primebrutethread again uses the brute force method but instead of multiplying the process and causing a ton of memory over head, instead we actually just enact a small void statement that loops until it's finished.
+Like our friend fork, the thread divides up the number by using the threads given to it but like I said, it doesn't multiply the program. Instead of cloning the program, it runs a small statement that the pthread asks for.
+Basically Thread -> void statement to run.
+The Primebrutethread does our traditional brute force method but with divided numbers and smaller memory allocation.
+Primesqrthread.c does the same thing as the Primesqrtfork.c but with less memory overhead.
+Sockets
+Next we have been playing with sockets and created two network like programs.
+The first is timeserv.c that when you use your client/telnet into the timeserv port that's reserved, it will tell you the time and disconnect you from the server.
+The second is ipaddr which returns to the user different network interfaces and the ip associated with them.

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