scripts/mtail
2015-03-10 22:15:59 +00:00

51 lines
905 B
Perl
Executable file

#!/usr/bin/perl
use strict;
use warnings FATAL => 'all';
use IO::Pipe;
my $pipe = IO::Pipe->new();
map { tail($_) } @ARGV;
$pipe->reader();
while (<$pipe>) {
print;
}
sub parse_host_file {
my $spec = shift;
if ( my ( $h, $f ) = $spec =~ m/^([^:]+):(.+)$/ ) {
return ( $h, $f );
}
else {
return ( undef, $spec );
}
}
sub tail {
my ( $spec ) = @_;
my ( $host, $file ) = parse_host_file($spec);
my $cmd = $host ? ['ssh', $host, 'tail', '-F', $file ] : ['tail', '-F', $file ];
my $prefix = $host ? "$host: " : "";
my $pid = fork();
if ( $pid ) { # parent
return $pid;
}
elsif ( defined($pid) ) { # child
$pipe->writer();
open( my $fh, '-|', @$cmd ) or exit 255;
while ( <$fh> ) {
s/^/$prefix/;
$pipe->print($_);
$pipe->flush();
}
close($fh);
exit 0;
}
else {
die "Failed to tail $spec (fork failed): $!";
}
}