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#include "include/system.h" /* just extern int strlen(char *str); */

int strlen(char *str)
{
    /* This loops through character array 'str', returning how
    *  many characters it needs to check before it finds a 0.
    *  In simple words, it returns the length in bytes of a string */
    int retval;
    for(retval = 0; *str != '\0'; str++) retval++;
    return retval;
    /* I have tried my own strlen function but it didn't help, this is a copy from howto */
}

/* This is a very simple main() function. */
void main()
{
    int i= strlen("Hello");
    /* ...and leave this loop in. There is an endless loop in
    *  'start.asm' also, if you accidentally delete this next line */
    for (;;);
}

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all:
	nasm -f aout -o start.o start.asm
	gcc -Wall -O -fstrength-reduce -fomit-frame-pointer -fleading-underscore -finline-functions -nostdinc -fno-builtin -c -o main.o main.c
	ld -T link.ld -o kernel.bin main.o start.o

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[heikki (14:01:49):~/ohjelmointi/kernu ]$make
nasm -f aout -o start.o start.asm
gcc -Wall -O -fstrength-reduce -fomit-frame-pointer -fleading-underscore -finline-functions -nostdinc -fno-builtin -c -o main.o main.c
main.c:20: warning: return type of 'main' is not `int'
main.c: In function `main':
main.c:21: warning: unused variable `i'
ld -T link.ld -o kernel.bin main.o start.o
[heikki (14:01:50):~/ohjelmointi/kernu ]$              

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  .data : AT(phys + (data - code))
  {
    data = .;
    *(.data)
    . = ALIGN(4096);
  }

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SECTIONS {
  .text 0x00100000 :{
    *(.text)
  }
  textEnd = .;
  .data :{
    *(.data)
    *(.rodata)
  }
  dataEnd = .;
  .bss :{
    *(.common)
    *(.bss)
  }
  bssEnd = .;
}