watch: enable autoflush for STDOUT and STDERR

In case output is redirected to a pipe, ensure stdout and stderr
are always unbuffered, as -watch may go long periods without
any output to fill up buffers.

diff --git a/script/public-inbox-watch b/script/public-inbox-watch
index ae7b70be355f056a0201f51a66bb089f2562371d..c07d45d74aeb2bb8b3c6478490bc108ad32268a4 100755 (executable)
--- a/script/public-inbox-watch
+++ b/script/public-inbox-watch
@@ -2,13 +2,15 @@
 # Copyright (C) 2016-2020 all contributors <meta@public-inbox.org>
 # License: AGPL-3.0+ <https://www.gnu.org/licenses/agpl-3.0.txt>
 use strict;
-use warnings;
+use IO::Handle;
 use PublicInbox::WatchMaildir;
 use PublicInbox::Config;
 use PublicInbox::DS;
 use PublicInbox::Sigfd;
 use PublicInbox::Syscall qw(SFD_NONBLOCK);
 my $oldset = PublicInbox::Sigfd::block_signals();
+STDOUT->autoflush(1);
+STDERR->autoflush(1);
 my ($config, $watch_md);
 my $reload = sub {
        $config = PublicInbox::Config->new;