Subject: Failure to employ proper diagnostic tools

(This message is being sent to all CPSC 360 students)

I have received two requests from students for help because
they were unable to send and/or receive for "unknown reasons".

The primary cause of the reason being unknown is that the
student(s) (1) don't use gdb and (2) also don't even bother
to turn on and or expand the diagnostic code I have
included in the notes :-(

When I included this diagnostic print in one fellow's
bind socket routine like this:

    73 #if 1
    74 fprintf(stderr, "Bind - Fam: %d Port: %d IP: %s \n",
    75 addr->sin_family,
    76 ntohs(addr->sin_port),
    77 inet_ntoa(addr->sin_addr));
    78 #endif


proj2 ==> udping -S -p 12345
ping interval:  1.00
count:          134217727
port:           12345
size:           12
server:         1
print flag:     1
s = 4

I get output like this:
Note that the port is (probably) in the
wrong byte order and the IP address which should be
0.0.0.0 is a rather bizarre looking random number and the
PF instead of being 2 is 49,288!!

Bind - Fam: 49288 Port: 37823 IP: 98.145.4.8
rc = -1
bind failed: Cannot assign requested address
am/proj2 ==>

Please be sure that you ENABLE ALL reasonable diagnostics
(which should go to stderr) BEFORE sending me your tar file.
Please be sure that you DISABLE time before turning in
your project.

----------------------------------------------
This same sad state of affairs can also be gleaned from gdb
as follows:

(gdb) b bind_socket
Breakpoint 1 at 0x8048fe3: file socklib.c, line 72.
(gdb) r -S -p 12345
Starting program: /home/westall/am/proj2/udping -S -p 12345
Reading symbols from shared object read from target memory...done.
Loaded system supplied DSO at 0xb7f33000
[Thread debugging using libthread_db enabled]
[New Thread -1208953152 (LWP 30501)]
ping interval:  1.00
count:          134217727
port:           12345
size:           12
server:         1
print flag:     1
s = 3
[Switching to Thread -1208953152 (LWP 30501)]

Breakpoint 1, bind_socket (sock=3, addr=0xbff329a8) at socklib.c:72
72        int rc = 0;
(gdb) print /x *addr
$1 = {sin_family = 0x29c8, sin_port = 0xbff3, sin_addr = {s_addr = 0x8049162}, sin_zero = {
    0xf4, 0xbf, 0x89, 0x0, 0x4, 0x0, 0x0, 0x0}}
(gdb)