>
> The following demo code should block on the call to accept
> but it doesn't in 2.3.x, (where x is 24,27,28,30,31, and 32pre2)
>
> 2.2.5, 2.2.13, and 2.2.14pre9 block as expected in accept()
>
> I'm getting
> ENOTCONN "Transport endpoint is not connected"
>
> The man page for accept(2) leads me to believe that it should block
>
> If no pending connections are present on the queue, and the
> socket is not marked as non- blocking, accept blocks the
> caller until a connection is present.
>
> I discovered this when attempting to build perl for 2.3.32pre2
> (I'm using libc5.4.44 if that matters)
> and it failed in when testing lib/io_unix
>
> I will appreciate your comments
>
> Thanks again,
> David Dyck
It may be that previous versions let you get away with muddy code.
There are several problems with the test code.
>
> #include <stdio.h>
> #include <unistd.h>
> #include <sys/types.h>
> #include <sys/socket.h>
> #include <sys/un.h>
>
> #define PATH "/tmp/sock-test"
> int main()
> {
> int s;
> pid_t pid;
> struct sockaddr_un sa = { AF_UNIX, PATH };
> char *buf[1024];
>
> unlink(PATH); /* just in case */
>
> s = socket(AF_UNIX, SOCK_STREAM, 0);
> if (s == -1) { perror("socket"); exit(1); }
>
> if (bind(s, (struct sockaddr *)&sa,
> strlen(sa.sun_path) + sizeof (sa.sun_family)) == -1)
> { perror("bind"); exit(1); }
>
> if (listen(s, 5) == -1) { perror("listen"); exit(1); }
>
> {
> int s2;
> int sa2_len;
> struct sockaddr_un sa2;
>
Here, the length of sa2, passed to accept via sa2_len is undefined.
The length should be initialized to the length of the structure so
accept() knows how much space is available. Accept() is probably
getting a 0, returning a bogus error-code.
> if ((s2=accept(s, (struct sockaddr *)&sa2, &sa2_len)) == -1)
> {perror("accept didn't block"); exit(1); }
> }
>
Cheers,
Dick Johnson
Penguin : Linux version 2.3.13 on an i686 machine (400.59 BogoMips).
Warning : The end of the world as we know it requires a new calendar.
Seconds : 1667624 (until Y2K)
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