| From: | Rudi Chiarito |
| Date: | 2 Sep 2000 at 16:30:30 |
| Subject: | Re: AMIOPEN: Socket Help |
On Fri, Sep 01, 2000 at 06:27:52AM -0700, Patrick Roberts wrote:
> Could someone more familiar with sockets than I am help me out. I started a
> port of libeasy_sock (socket library I've used under Linux). I've got it
> compiling fine, but when I run the test it gives me an error about the socket
> being busy. Could someone take a look at it? It's been uploaded to the CVS
> server as libeasy_socket.
The problem(s) is (are) in the test program, which seems to have been
adapted from a typical Unix (ie forking) program in a hurry.
First of all, there's argument checking:
if (argc > 2 && argc < 4) {
usage(argv[0]);
exit(0);
}
If I run the program with no arguments (which is the first thing I did),
the check above fails to print the usage message and bail out.
Immediately after that, there's this call, which will cause an access to
an illegal memory address, because there's no valid argv[1]:
instance = atoi(argv[1]);
I suppose you might want to change to above to something like "argc != 2
&& argc != 4)".
Then, for both the client and the server, you call bind(). That's why you
find a busy socket. The client should use connect(), which, for a
not-yet-bound socket, automatically calls bind(), telling it "allocate
any of the free ports". After changing the one-line bind() statement to
if (instance == 0)
sock = easy_tcp_bind(host1,port1,BACKLOG);
else
sock = easy_tcp_connect(host1,port1);
the client runs successfully with this output:
20000807:/libeasy_socket$ ./easy_test_Ami 1
Client (155): Connecting to 127.0.0.1 on port 7001...done.
== 155 == Write char: 'e'
== 155 == Write short: 127
== 155 == Write int: 2147483647
== 155 == Write long: -9223372036854775808
== 155 == Write float: 4010.000244
== 155 == Write double: 2000.010400
== 155 == Write string: "This is a test string"
== 155 == Write char: 'E'
== 155 == Write short: -128
== 155 == Write int: -2147483648
== 155 == Write long: 9223372036854775807
== 155 == Write float: 1234.002930
== 155 == Write double: 2050.014800
== 155 == Write string: "This is another test string"
Client (155) test completed.
The server complains with several error messages, you might want to check
carefully the test and the library to find what's wrong.