#!/usr/bin/env perl
use 5.016;
use autodie;
use warnings;

our $VERSION = 'v.0.0.1';

say qx[/bin/ls];

exit 0;
__END__

##</code><code>##

$ perlcritic -1 syscall1.pl 
Backtick operator used at line 8, column 5.  Use IPC::Open3 instead.  (Severity: 3)

##</code><code>##

#!/usr/bin/env perl
use 5.016;
use autodie;
use warnings;
use English '-no_match_vars';
use IPC::Open3;
use Symbol 'gensym';
use Readonly;

our $VERSION = 'v.0.0.2';

say system_ipc_open3('/bin/ls')->{'output'};

sub system_ipc_open3 {
    my @command = map { split m{\s+}xms } @ARG;

    Readonly my $SYSCALL_EXIT_STATUS_MASK => 8;
    Readonly my $BUFFER_SIZE              => 2_000_000;

    my (
        $child_in_fh, $child_out_fh, $child_err_fh,
        $child_in,    $child_out,    $child_err,
        $buffer,      $child_pid,    $child_exit_status
    ) = q[];

    $child_err_fh = gensym;
    $child_pid = open3( $child_in_fh, $child_out_fh, $child_err_fh,
        @command );
    $child_exit_status = $CHILD_ERROR >> $SYSCALL_EXIT_STATUS_MASK;

    while ( my $read = sysread $child_out_fh, $buffer,
        $BUFFER_SIZE ) {
        $child_out .= $buffer;
    }
    while ( my $read = sysread $child_err_fh, $buffer,
        $BUFFER_SIZE ) {
        $child_err .= $buffer;
    }

    waitpid $child_pid, 0;

    return {
        exit_status => $child_exit_status,
        error       => $child_err || q[],
        output      => $child_out || q[],
    };
}

exit 0;
__END__