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• https://intellectualmathematics.com/

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add: Add file contents to the index

• Stage files with confirmation (commit only part of a file)
  • git add --patch (git add -p)

branch: List, create, or delete branches

• Delete local branch if it has already been fully merged in its upstream branch
  • git branch -d <branch_name>
• Delete local branch, irrespective of its merged status
  • git branch -D <branch_name>

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Definition: assembly routines written as an inline function. Allows one to access architecture dependent instructions not available in C.

Form: must be inside of a function beginning with either 'asm' or '__asm__'

int main(){
    // volatile keyword tells the compiler to not optimize this area of code. The compiled binary will contain this exact sequence of code
    // optional: output operands, input operands, or clobbered registers
    __asm__ __volatile__ (
        <assembler template>
 ; 

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32-bit ELF binary

how to assemble and link:

nasm -f elf32 -o <filename>.o <filename>.asm
ld -m elf_i386 -o <filename> <filename>.o

template code (hello world):

section .text
global _start

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// how to compile: gcc dynamic_loading.c -o dynamic_loading -ldl
#include <stdlib.h>
#include <stdio.h>
#include <dlfcn.h>
#include <string.h>
 
int main(int argc, char **argv) {
    void *handle;
    void (*go)(char *);
 

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#include <stdio.h>
#include <stdlib.h>
#include <time.h>

int main(){
    // use current time to seed the prng used by rand()
    // if srand is not called (default: srand(1)), rand() will always generate the same sequence
    srand(time(0));
    for(int i=0; i<3; i++)
      printf("%d\n", rand());