From: Barney Wolff In porting (if I can glorify it by that word) ISS to Unixware (SVR4.2) on a 486, I noticed one really serious bug and some cosmetic stuff. The serious bug is a missing htonl on opening connections - with the result that you're really opening a connection to the byte-reversed address on a little-endian machine. The other functional change I put in was to time out connect attempts - if no reset comes back, the connect() call (at least on Unixware) seems never to time out. This way, I can test (my own domain only) from outside the firewall, or get by a machine that's powered off, or test a dos machine whose stack doesn't bother to send a reset. There is an apparent Unixware bug in getservbyport() - instead of taking the int port that the man page says it does, it really needs htons((short) port). I tested this outside iss, and that's the way it is. Here is the diff of my version with the distributed iss.c : 45d44 < #include 87c86 < void donothing(int sig) /* Signal sets done variable to tell program --- > donothing() /* Signal sets done variable to tell program 129,130c128 < a.sin_addr.s_addr = htonl(x); /* this is the only critical change */ < alarm((sec == 0) ? 7 : sec); --- > a.sin_addr.s_addr = x; 132d129 < alarm(0); 306c303 < int l, l1; size_t i; --- > int l, l1, i; 383c380 < int l, lp1; size_t i; --- > int l, lp1, i; 762a760 > extern int inet_addr(); 812d809 < alarm((sec == 0) ? 7 : sec); 818c815 < if ((ServiceEntryPointer = getservbyport(htons((short)Port), "tcp")) != --- > if ((ServiceEntryPointer = getservbyport(Port, "tcp")) != 825d821 < alarm(0); 910,913d905 < #ifdef sun < siginterrupt(SIGALRM, 1); < #endif < signal(SIGALRM, donothing); 935a928,931 > #ifdef sun > siginterrupt(SIGALRM, 1); > #endif > signal(SIGALRM, donothing); And the Makefile needs the libraries listed: $(CC) -o $@ iss.o -lnsl -lsocket /usr/ucblib/libucb.a Anyway, thanks for contributing a useful piece of software! Barney Wolff, Pres. Voice: 914-591-6572 Databus Inc. Fax: 914-591-5677 15 Victor Drive Internet: barney@databus.com Irvington, NY 10533-1919 USA At the corner of database & datacomm