Pre-Processor

#include<stdio.h>
int main()
{
    fprintf(stdout, "Hello, World!\n");
    return(0);
}

Compile & Run

gcc -S hello.c (Compiles To Assembly)

gcc -o hello hello.c (Compiles .C file into fully executable file)

./hello (Runs the program) 

Signed   char
Unsigned short
         long      int
         long long
         float
         double
         long double

stdin
stdout
stderr

Diff (Compares two files for differences. Returns nothing if file is an exact copy.)

ERROR Messages from compiling. Ex:

lab46:Thu Jan 22:~/src/cprog$ gcc -o broken broken1.c 
broken1.c: In function 'main':
broken1.c:4:35: error: expected ')' before ';' token
  fprintf(stdout, "Hello, World!\n";
                                   ^
broken1.c:6:1: error: expected ';' before '}' token
 }
 ^
lab46:Thu Jan 22:~/src/cprog$ 

#include <stdio.h>
int main()
{
        int input; //Declare a variable.
        input=0; //Initialize variable. (int input=0;)
        int result=0;
        fprintf(stdout,"Enter A Number: ");
        fscanf(stdin,"%d",&input);//Format %
        result=input*36; //Calculate input*36
        fprintf(stdout,"%.4d*36=%d\n",input,result);
        return(0);
}

lab46:Thu Jan 29:~/src/cprog$ ./io0 
Enter A Number: 9999
9999*36=359964

 #include <stdio.h>                                                          
#include <stdlib.h>
 
int main()
{
    int input, fst, mod;
    fprintf(stdout,"Enter a two digit number ending in five: ");
    fscanf(stdin,"%d",&input);
    mod=(input%5);
    while (( mod != 0) && (input > 95) || (input < 15))
             {
                 fprintf(stdout, "\noops! Number should fit this criteria.\nA    ny number ending in 5 rangeing between 15-95: ");
                 fscanf(stdin, "%d",&input);
             }
         fst = ((input-5)/10)*(((input-5)/10)+1);
         fprintf(stdout,"%d*%d=%d25",input,input,fst);
         fprintf(stdout,"\n%d",input%5);
 
         return(0);
 }

#include <stdio.h>
#include <stdlib.h>
#include <string.h>
 
 
int main()
{
        int input, result, result1, result2;
        fprintf(stdout, "Enter a two or three digit number to be multiplyed by 11\n");
        fscanf(stdin,"%d", &input);
        result=(input%10);
        result1=(input/10);
        result2=(result+result1);
        if (result2 > 9)
        {
                result1=result1+(result2/10);
                result2=(result2%10);
        }
        fprintf(stdout, "11*%d=%d%d%d\n", input, result1, result2, result);
        return(0);
}

awsome.c

#include <stdio.h>
#include <stdlib.h>
#include <time.h>
int main()
{
        int guess, pick, num=0, done=0;
        srand(time(NULL));
        pick=rand()%10+1;
        do{
                fprintf(stdout, "Guess a number between 1-10: ");
                fscanf(stdin, "%d", &guess);
                if (guess==pick)
                {
                        fprintf(stdout, "Correct!\n");
                        done=1;
                }
                else if (guess > pick)
                {
                        fprintf(stdout, "Guess too high\n");
                }
                else
                {
                        fprintf(stdout, "Guess too low\n");
                }
        }while((done != 1)&&(num++<5));
 
//  while (i>0)
//      {
//      }
//      for (i=0; i>0; i++)
//      {
//      }
//      do{
//      }while(condition);
        return(0);
}

aray.c

  1 //int b[5];                                                                 
  2 //b[0]=12;
  3 //b[1]=b[0]+a;
  4 //b[c]=b[0]*2;
  5 //int d[2][3];
  6 //int e[2][3][2];
  7 //[][][][][]

#include  <stdio.h>
#include <stdlib.h>
 
int main(int argc, char **argv)
{
        int i;
        fprintf(stdout,"%s was called with %d arguments. They are: \n", argv[0],argc);
        for(i=0; i<argc; i++)
        {
                fprintf(stdout,"argv[%d]: %s \n", i, argv[i]);
        }
}

#include <stdio.h>
#include <stdlib.h>
 
int main()
{
        char *b;
        char size;
        size=sizeof(char*);
        fprintf(stdout,"\n%d\n%d",size,b);
        return(0);
}

#include <stdio.h>
#include <stdlib.h>
 
char *allthezeros(char);
char howbigthastring(char *);
char howbigthastringwithmax(char *, char);
void showmethenumber(char *, char);
 
int  main(int argc, char **argv)
{
        int  i;
        char *number;
 
        if (argc <  1)
        {
                fprintf(stderr, "Error! Not enough arguments!\n");
                exit (1);
        }
        else if (argc >  1)
        {
                fprintf(stderr, "Error! Too many arguments!\n");
                exit (2);
        }
 
        number = allthezeros(8);
 
        for(i = 0; i < i < 8;)
         number[i] = *(*(argv+1)+i);
                 i++;
        }
 
        showmethenumber(number, howbigthastring(number));
 
        return(0);
}
 
char *allthezeros(char len)
{
        char *data;
        //char  data[];
        int i;
        data = (char *) malloc (sizeof(char) * len);
 
        for (i = 0; i < len; i++)
        {
                //data[i] = 0;
                *(data+i) = 0;
        }
        return(data);
}
 
char howbigthastring(char *thearray)
{
        char i = 0;
 while(*(thearray+1) == '\0')
        {
                 i++;
        }
}
void showmethenumber(char *stuff, char longness)
{
        char i;
        for (i = 0; i < longness; i++)
        {
                fputc(*(stuff+i), stdout);
                fputc('\n',stdout);
        }
}

rectangle

#include <stdio.h>                                                                                       
#include <stdlib.h>
 
class rectangle{
public:
    rectangle(); //constructor
    rectangle(int,int);
    int area();
    int perimeter();
    int getLength();
    void setLength(int);
    int getWidth();
    void setWidth(int);
 
private:
    int length;
    int width;
};
 
rectangle::rectangle(){
    length=0;
    width=0;
}
rectangle::rectangle(int length, int width){
    this->length=length;
    this->width=width;
}
int rectangle::area(){
 
    return(length*width);
}
int rectangle::perimeter(){
    return(2*length+2*width);
}
int rectangle::getLength(){
    return(length);
}
void rectangle::setLength(int length){
    this->length=length;
}
int rectangle::getWidth(){
    return(width);
}
void rectangle::setWidth(int width){
    this->width=width;
}
 
int main()
{
    rectangle r1, *r2;
    r2 = new rectangle(4,7);
    r1.setLength(9);
    r1.setWidth(11);
    r2->setWidth(8);
    fprintf(stdout,"r1 length is %d\n",r1.getLength());
    fprintf(stdout,"r1 width is %d\n",r1.getWidth());
    fprintf(stdout,"r1 area is %d\n",r1.area());
    fprintf(stdout,"r1 perimeter %d\n",r1.perimeter());
    printf("\n");
    fprintf(stdout,"r2 length is %d\n",r2->getLength());
    fprintf(stdout,"r2 width is %d\n",r2->getWidth());
    fprintf(stdout,"r2 area is %d\n",r2->area());
    fprintf(stdout,"r2 perimeter %d\n",r2->perimeter());
 
    return(0);
}  

Classes Cprog~ April 09, 2015

C++ -classes/objects

#include <stdio.h> | #include <cstdio> #include <stdlib.h>| #include <cstdlib>

g++ .cc, .c++, .cpp, .C

public, protected, private

Model number, Service Tag(Manufacturer support) Bios Version (2.4.1)

Clock Speed- Rate at which the processor can handle/process a given set of instructions.

Cores- CPU's Capability to handle multi-tasking or multiple instructions.

SATA Ports- Hard Drives, CD/DVD Drives (0-4)

http://10.80.2.3:3142/

Linux from scratch!

This will be an ongoing project.

I have collected various resources for this endeavor. For now I present today's notes along with some ideas/theories and steps.

System D? or Traditional Linux?

cfdisk, fdisk, mkfs

I had created a 10.00GB partition on the left over space of the host computer's hard drive using cfdisk.

The partition file can be found in /dev.

The partition was then set to use the current ext4 file system using mkfs.

I would then prepare to mount the newly partitioned space to /mnt where from there an environment variable would be created to point to the mounted partition /mnt/LFS.

export LFS=/mnt/lfs

Enabling the use of $LFS

Notes:

MD5SUM-Checks, Data authentication detects changes in files that could cause errors using cartographic hashes (128 bit)

SHA-256, WhirlPool, Ubuntu Hashes PGP Signature

ACL(Access Control List)

“Which users or system processes are granted access to objects, as well as what operations are allowed on a given object.”

ATTR(Attribute)

“Extended attributes are name: value pairs associated permanently with files and directories, similar to the environment strings associated with a process.”

AUTOCONF(AUTO Configure)

“Extensible Package of M4 macros. Produce shell scripts to automatically configure software source code packages. Creates a configuration script for a package from a template file that lists the OS's features that the package can use.”

Automake, Bash, BC, Binutils, Bison, Bzip, Check, Coreutils, D-Bus, Deja-GNU, Diffutils,E2fsprogs, Expat, Expact, File, Finutils, Flex, Gawk, GCC, GDBM, Gettext, Glibc, GMP, Gperf, Grep, Graff, Grub, Gzip, Lana-ETC, Inetutils, Intiital, IProute2, KBD, Kmod, Less, Libcap, Libpipeline, Libtool Linux, M4, Make, ManDB, Man Pages, MPC, MPFN, NCurses, Patch, Tar, TC1, Textinfo, Time Zone Data, Util-Linux, VIM, XML, XZwtil, Xlib (There may be some typos here.)

groupadd (name of group) useradd -s(choose default user shell) /bin/bash -g (add user to lfs) lfs -m (creates a home directory for lfs) -k /dev/null (prevents copying of files from a skeleton directory) chown -v lfs (make user owner of directory) su - lfs (substitute or switch user)

Standard build/compile time for source packages.

Check or test for proper compilation.

Info: Binutils (Binary Utilities) provides a lot of linking to assembly source, object files and profile data. The basis for managing and creating “binary” programs.

First pass of binutils successfully completed. (note. Don't delete the lfs home directory) Used the make command to build binutils. Then make install for installation.

GNU Compiler collection.

“The GNU Compiler Collection includes front ends for C, C++, Objective-C, Fortran, Java, Ada, and Go, as well as libraries for these languages (libstdc++, libgcj,…). GCC was originally written as the compiler for the GNU operating system. The GNU system was developed to be 100% free software, free in the sense that it respects the user's freedom.” https://gcc.gnu.org/

Glibc: Provides the standard c library for the kernel.

Linux API Headers: The kernel itself and modifications to header files(.h) that may be out of date or incompatible?

The remaining installation will be done in the chroot of the mini linux system.

NODES:Directories are tables that map directories and files to iNodes. Names of a directory or files are stored in a separate inode. (The name inode map)

Creating Essential File-system and Symlinks: The operating system needs to mount a virtual file-system for proper communication with the kernel.

Localedef: The following instructions will install the minimum set of locales necessary for the optimal coverage of tests.