Experimental Physics and
Industrial Control System

"Mark Rivers" <[email protected]> · Wed, 20 Jan 2010 07:57:20 -0600

Hi Paul,

You are correct, drvAsynIPServerPortConfigure can only handle TCP, and the documentation is wrong.

Eric Norum looked at adding UDP support to this code back in December.  He concluded it was a fairly big job, but he did fix the sscanf problem for the next release.  If you or someone else wants to add UDP support that would be great!

Mark

________________________________

From: [email protected] on behalf of Paul Hamadyk
Sent: Wed 1/20/2010 2:59 AM
To: EPICS tech-talk
Subject: drvAsynIPServerPortConfigure

Hello,

The asyn documentation says that drvAsynIPServerPortConfigure can be a
TCP or UDP server but the source code in
asyn/drvAsynSerial/drvAsynIPServerPort.c does a

listen(tty->fd, tty->maxClients);

There is no recvfrom call so surely this is TCP only?

Also this code below fails to convert the protocol string in the string
"localhost:9600 udp" because the format string uses %ud which looks for
an unsigned integer followed by a 'd'. It should be just "%u". This
stops it from ever seeing the "udp" protocol specifier. This exists in
all of the version of asyn I have looked at (4-9 to 4-12).

/*
 * Parse configuration parameters
 */

  protocol[0] = '\0';
  if (((cp = strchr(serverInfo, ':')) == NULL)
     || (sscanf(cp, ":%ud %5s", &tty->portNumber, protocol) < 1))
  {
    printf("drvAsynIPPortConfigure: \"%s\" is not of the form
\"<host>:<port>[protocol]\"\n",tty->serverInfo);
    ttyCleanup(tty);
    return -1;
  }

Would it be possible to use stream device to handle incoming UDP data?

Paul.

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Experimental Physics and Industrial Control System

Experimental Physics and
Industrial Control System