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1#!/usr/bin/env perl2# SPDX-License-Identifier: GPL-2.03# Prefix all lines with "# ", unbuffered. Command being piped in may need4# to have unbuffering forced with "stdbuf -i0 -o0 -e0 $cmd".5use strict;6use IO::Handle;7 8binmode STDIN;9binmode STDOUT;10 11STDOUT->autoflush(1);12 13my $needed = 1;14while (1) {15 my $char;16 my $bytes = sysread(STDIN, $char, 1);17 exit 0 if ($bytes == 0);18 if ($needed) {19 print "# ";20 $needed = 0;21 }22 print $char;23 $needed = 1 if ($char eq "\n");24}25