You need to learn more about threads in general...... shared variables need to be declared BEFORE the thread is created. This should get you going in the right direction.

#!/usr/bin/perl -w
use strict;
use warnings;
use threads;
use threads::shared;
use Glib qw/TRUE FALSE/;

my $user : shared = 'uas';
my $server : shared = 'updraft.unl.edu';
my $local_waypoint : shared = '/local';
my $remote_waypoint : shared = '/remote';
my $waytemp : shared = 'waytemp';
my $wayfinal : shared = 'wayfinal';
my $local_uaspos : shared = '/local';
my $remote_uaspos : shared = '/remote';
my $local_uas : shared = '/local';
my $remote_uas : shared = '/remote';
my $die : shared = 0;
my $sftp_connect : shared = 0;

#threads
my $thread_1 = threads->new( \&sftp);
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