//#include <sys/types.h>
//#include <sys/stat.h>
#include <fcntl.h>
#include <stdlib.h>
//#include <unistd.h>
int main(int argc, char* argv[])
{

    int fileFrom=open(argv[1],O_RDONLY);
    int fileTo=open("test5.txt",O_RDWR|O_CREAT| O_TRUNC| O_APPEND);
    char *buff=malloc(1);

    if(fileTo==-1 || fileFrom==-1)
        perror("zjebalo sie");

    while(read(fileFrom,buff,1))
    {
        if(*buff>='A' &&*buff<='Z')
            *buff=*buff+32;

        if(write(fileTo,buff,1))
            printf("writing...\n");

    }
    free(buff);
    close(fileTo);
    close(fileFrom);

    return 0;
}