Suvidh, thanks for the explanation (!). i wanted to be sure i am doing my debuging modifications right. BTW do you know, why my compiler could complain when i do sth like this in network device driver - 8159too.c ******************************************** char *moj_bufor; //at the beginning of the file moj_bufor = vmalloc(4000); /* somewhere later in the code but inside an existinf fucntion def */ sprintf( &(moj_bufor+offset), "some text"); // offset is taken from strlen(moj_bufor) ******************************************** ^ ..it says: " invalid lvalue in unary `&' " what i did wrong? thanks in advance. best regards adam - : send the line "unsubscribe linux-net" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html