A spinner in a thread is your best bet.
#!/usr/bin/perl
use strict;
use threads qw[ yield ];
use threads::shared;
# by chanio of perlmonks
# This alternative should print a line only if it succeeds
# in what is doing as job. That way, there is a real
# significance of the spinning wheel (sort of:). When the
# job is not succeeding, the wheel should stay calm (panic!).
my $ready : shared = 0;
my $isOk : shared = 0;
async {
local $| = 1;
while ( !$ready ) {
do {
select undef, undef, undef, 0.2;
printf "\r ($_)" if ($isOk);
}
for qw[ / - \ | * ];
}
print "\rReady";
$ready = 0;
}
->detach;
# do your work here
for ( 1 .. 10 ) {
## Busy, busy, busy
$isOk = 1;
sleep 1;
$isOk = 0;
}
$isOk = 0;
$ready = 1;
yield while $ready;
