This perl script is an old piece of code that will create a Windows version text string. I am sure someone might find this useful. #!/usr/bin/perl use warnings; @t = localtime(time()); $yr = ($t[5] + 1900) -1; $sr = int(( $t [4]/4) + 1); $v = int("$t[7]$t[2]$t[1]$t[0]"*((rand(rand(10) + 1 )))); print … Read more
Funny and cool Linux tips 1337 or Leet in the UNIX time. -01:44:57– gordon@deusexmachina [~]$ date +%s 1337096699-01:44:57– gordon@deusexmachina [~]$ date +%s 1337096699 The missing days in 1752. I have mentioned this before, but it is worth mentioning again. -01:45:31– gordon@deusexmachina [~]$ cal 9 1752 September 1752 Su Mo Tu We Th Fr Sa 1 … Read more
This is how to actually count the lines of code in your C project on Linux. Some people advocate using wc -l, but that would not suit our purposes. The cloc utility is able to do this and more. Firstly, install this utility. sudo apt install clocsudo apt install cloc Then run the utility in … Read more
Not a bad little program, and I got the code to work first time, not bad. Writing code in standard C is better than C++ or C#, the old C language is still the best. The whole Linux kernel is written in C and if it is good enough for that project, it is good … Read more
I think I may have posted this before, but this is a little program I am working on that writes a text string to a file. I have got it to work perfectly and it compiles without errors using gcc -Wall. /* * This program is free software; you can redistribute it and/or modify * … Read more
This program will return the IP address of a specified network interface. Use the –ip parameter to get the IP. For example, this will show the IP address of an Ethernet interface: my-ip –ip eth0. 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 … Read more
This is a simple random number example in C. This will print a random number from 1 – 64. #include <stdio.h> #include <stdlib.h> int main (void) { srand(time(NULL)); int r = rand() % 64; printf("Random INT: %i\n", r); return 0; }#include <stdio.h> #include <stdlib.h> int main (void) { srand(time(NULL)); int r … Read more
How to define a string and print it out with the printf() function. #include <stdio.h> /* Defining a global string. */ #define hi "Hello Sire." int main(void) { /* Printing out the string. */ printf("%s\n", hi); return 0; }#include <stdio.h> /* Defining a global string. */ #define hi "Hello Sire." int … Read more
Do a simple function call in C. This code snippet shows how to do this This simple C code snippet shows how to do a function call in C. This calls the hi() function and runs it in main(). Very simple but useful code. And this does not need to call any include files. As … Read more
This code will pick a random word from the x[] array and include it in the printed string. This program will also get your current Linux username to customize the output. I am sure this code would be very useful to someone who wants to know how to handle arrays in C. #include <stdio.h> #include … Read more
This code will print the contents of a file to the terminal. Feel free to use this in your own projects if you wish. #include <stdio.h> #define MEM "/proc/diskstats" int main (void) { FILE *g; char Meminfo[40]; g = fopen(MEM, "r"); if(!g) { printf ("Sorry, I cannot open: %s.\n", MEM); } else … Read more
This loop I wrote in C enables if statements inside a loop. This could be a useful thing to know. #include <stdio.h> int main(void) { int k; for (k = 0; k < 16; k++) { printf("* *\n"); if (k == 4 || k == 12) { printf("\n\t\t-\n"); } if (k == 8) … Read more
This is a very simple Hello World program that you can write in C. int main (void) { write (1, "Hello World\n", 14); return 0; }int main (void) { write (1, "Hello World\n", 14); return 0; } Just compile the program like this: localhost% cc minimal.c -o small minimal.c: In function ‘main’: minimal.c:2:5: warning: … Read more
This code sample will render a spiral on your terminal when you compile and execute it. Very interesting indeed. #include <sstream> #include <iostream> #include <string> std::string rle = "32 2@14 1n16 11@9 2@10 1n13 3@13 3@8 1@7 1n10 2@21 2@7 1@5 1n7 2@27 1@6 1@4 " "1n6 1@10 10@10 2@5 2@2 1n4 2@7 4@9 … Read more
This code prints out a tick sign using asterisks. I tested this code on Fedora 19 and gcc 4.8 and it compiles without any problems. #include <iostream> #include <iomanip> using std::cout; int main() { cout<<std::setw(8)<<"*"<<"n"; cout<<std::setw(7)<<"*"<<"n"; cout<<std::setw(6)<<"*"<<"n"; cout<<"* *"<<"n"<<"* *"<<"n"<<"*"; cout<< "n"; return 0; }#include <iostream> #include <iomanip> using std::cout; … Read more
http://gentoomen.org/tutorials/resources.html. The gentoomen.org resources page. Very good list of links to various tutorials and help pages. http://tldp.org/LDP/abs/html/. The Advanced BASH scripting guide. ftp://ftp.vim.org/pub/vim/doc/book/vimbook-OPL.pdf. The VIM guideboook. http://stommel.tamu.edu/~baum/programming.html. 3000 useful guides to programming and Linux documentation and help pages. http://samizdat.mines.edu/howto/HowToBeAProgrammer.html. How to be a programmer. A short but comprehensive summary. http://www.psychocats.net/ubuntu/index. Ubuntu resources page. Everything you … Read more
This code sample shows how we are wrapping a printf() statement onto multiple lines using backslashes. #include "stdio.h" #define hello "Hello World." int main(int argc, char* argv[]) { printf("This is a very long sentence we are handing down\n"\ "Mr smith, do you have anything to say for yourself"\ "?"); printf("%s\n", hello); … Read more
This programming trick is pretty cool, you can run the /bin/sh shell with a C program. The execve() function is useful for running a command within a C program and passing arguments to it, but I have replaced the arguments with NULL instead, that is what you put when you do not need arguments. #include … Read more
A very obfuscated C program. typedef unsigned char t;t*F="%c",l[]="|\\/=_ \n](.\0(),*(.(=(}*.)[[*.",N=’\n’,* r;typedef(*H)();extern H Ar;Q(a){return(a|-a)>>31;}H S(c,a){return(H)(a&~c|(int )Ar&c);}extern t*ist;V(t*u){*u^=*u&2^(*u>>7)*185;}Z(t*u,t n){*u-=n;}e(t c,H h){ R(h,Q(* r^c));} I(){r=l +7-4*Q( getchar ()^*l); }R(H h, int c){Ar=S (c,h);- main() ;}P(){r ++;}z() { O(&N);} O(t*c){ printf( F,+*c); }T(){r= "This is not a function\n" ;}w(U){ U=Z(r,8 ); r-=~Q(* r/8-4); return 0; }M(){r= ist-68; } h(){t … Read more
This code snippet will run the date command. The execl() function is very useful for executing a command within your C program.You replace the NULL identifiers with any extra arguments to pass to the program. I prefer this over the system() function. #include <unistd.h> int main(void) { execl("/bin/date", "%c", NULL, NULL, NULL); return … Read more