Re: [Fetchmail-users] Flush `Trying to connect...' Message.

[Ralph C. <ra...@in...>]

Hi Mattias,

> > If a server is slow to accept a connection then I find the `Trying
> > to connect to 1.2.3.4/993' message only appears on SIGINT whereas it
> > would be useful to know that's what's being attempted during the
> > delay.  Please flush this part of the line rather than having it
> > appear only when the whole line is finished.
> >
> > This `two part line' style of output may occur elsewhere and need
> > flushing benefit from flushing there too.
>
> Please heed <http://www.fetchmail.info/fetchmail-FAQ.html#G3>

fetchmail 6.3.26-6 on Arch Linux.

To re-create the problem, run this Perl script to listen(2) on TCP
socket 31415, but not accept(2).

    #! /usr/bin/perl -w

    use Socket;

    socket(Server, PF_INET, SOCK_STREAM, getprotobyname('tcp')) &&
    bind(Server, sockaddr_in(31415, INADDR_ANY)) &&
    listen(Server, 0) or die;

    print "sleeping\n";
    sleep(3600);

Then run fetchmail whilst Perl's sleeping, hitting Enter when prompted
for a password.

    LC_ALL=C fetchmail -f /dev/null -v -p imap -P 31415 127.1

I see

    Enter password for ralph@127.1: 
    fetchmail: 6.3.26 querying 127.1 (protocol IMAP) at Wed Jun 13 06:46:17 2018: poll started

After waiting a while I Ctrl-C to send SIGINT.

    ^CTrying to connect to 127.0.0.1/31415...fetchmail: terminated with signal 2
    $

If that doesn't happen because the connection succeeds then stop
fetchmail and re-run it;  it's probably the listen(2)'s queue implicitly
accepting the connection.

My desired output is

    Trying to connect to 127.0.0.1/31415...^Cfetchmail: terminated with signal 2

where the text before `^C' appeared without the SIGINT.

-- 
Cheers, Ralph.
https://plus.google.com/+RalphCorderoy