use Fcntl qw(:DEFAULT); # omit
my $rv = sysopen(F, '/path/name', O_RDONLY);
$rv = sysopen(*F, '/path_name', O_RDWR | O_TRUNC);
sysopen(my $fh, '/path/name', O_WRONLY | O_CREAT, 0777);
my $mode;
sysopen($fh, '/path/name', O_WRONLY | O_CREAT, $mode);
sysopen(*$fh, '/path/name', O_WRONLY | O_CREAT | O_EXCL);
my $flags;
sysopen($fh, '/path/name', $flags)
