The following code fragment is part of a nagios check that is running on about 70 hosts. There's one host which fails the close() and I don't know why. Maybe some exotic edge case? 
use strict;
use warnings;
require 5.008_008;
use Carp;
use English qw( -no_match_vars );
[...]
open my $fh, '-|', "$command"
  or carp "Error while executing command:$ERRNO\n";
my @command_output = <$fh>;
close $fh 
  or carp "ERROR: Couldn't close filehandle: $ERRNO\n";

[download]
(I'm wondering why there's carp instead of croak, but that's a different issue.)

The open/close is part of a subroutine, $command is provided as a parameter. In this case it's "LC_ALL=C sudo mpt-status --newstyle --probe_id" and the command output is:

Checking for SCSI ID:0
ioc:0 vol_id:0 type:IM raidlevel:RAID-1 num_disks:2 size(GB):148 state
+: OPTIMAL flags: ENABLED
ioc:0 phys_id:1 scsi_id:8 vendor:ATA      product_id:SAMSUNG HE160HJ  
+revision:0-24 size(GB):149 state: ONLINE flags: NONE sync_state: 100 
+ASC/ASCQ:0xff/0xff SMART ASC/ASCQ:0xff/0xff
ioc:0 phys_id:0 scsi_id:1 vendor:ATA      product_id:ST3160812AS      
+revision:J    size(GB):149 state: ONLINE flags: NONE sync_state: 100 
+ASC/ASCQ:0xff/0xff SMART ASC/ASCQ:0xff/0xff
ioc:0 spare_id:2 scsi_id:255 vendor: product_id: revision: size(GB):14
+9 state: MISSING flags: OUT_OF_SYNC sync_state: n/a ASC/ASCQ:0x00/0x0
+0 SMART ASC/ASCQ:0x00/0x00
scsi_id:1 100%
scsi_id:0 100%

[download]
The server is running Ubuntu 12.04 LTS, like at least 40 other ones. (The other ones don't exhibit this behaviour.) The installed perl version is 5.14.2-6ubuntu2.4.

ERRATA: I provided the wrong command, it wasn't 'LC_ALL=C sudo mpt-status --controller $id' but 'LC_ALL=C sudo mpt-status --newstyle --probe_id'. The output is/was correct.

In reply to close $fh fails on a single host - looking for explanation by Monk::Thomas

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