#include <stdio.h>
#include <string.h>
#include <unistd.h>
#include <fcntl.h>

int main(int argc, char *argv[])
{

printf("create file and open to read\n");
int u = (int)argv[2];
u=u-2;
int file = creat(argv[1], atoi(argv[2]));
  if (file == -1)
  {
    perror("Error while creating file: ");
    return 0;
  }

printf("write to the file \"many street\"\n");
char buff[100] = "one street \n two street";
write(file, buff, strlen(buff));
close(file); //Закрываем файл

//Открываем и считываем
char buff2[100];
file = open(argv[1], O_RDONLY);
read(file, buff2, strlen(buff));
close(file);

printf("read to file 1: %s\n", buff2);

printf("\nread file в режиме чтения\n");
buff2[0]='\0';
file = open(argv[1], O_RDONLY);
  if (file == -1)
  {
    perror("Error while opening file: ");
    return 0;
  }
read(file, buff2, strlen(buff));
printf("read file 2:\n %s\n", buff2);
close(file);

printf("\nread file в режиме чтения и записи\n"); 
char buff3[100];
buff3[0]='\0';
file = open(argv[1], atoi(argv[2]));
  if (file == -1)
  {
    perror("Error while opening file: ");
    return 0;
  }
read(file, buff3, strlen(buff));
printf("read file 3:\n %s\n", buff3);
close(file);
return(0);
}