char* ltrim(char* source)
{
    char* p=source;
    char* p2=source;
    while(*p!='\0')
    {
        if(*p!=0x20) break;
        p++;
    }
    while(*p!='\0')
    {
        *source=*p;
        source++;
        p++;
    }
    *source='\0';
    return p2;
}