while (<IN0>) {
    my $currentURI = $_; 
    chomp($currentURI); 
    my @tags = eval {        # Use eval to make this safe, $@ will contain any error
        $c->posts_for(uri =>"$currentURI");
    }
    my $error = $@;
    if (defined($error)) {
        warn($error);        # If eval failed, warn and skip to next line
        next;
    }
    if (! @tags) {
        next;                # Assuming no tags means go to next line in input
    }
    ... do something ...
}