Description of problem:

In Fedora 27, the 'niceload' command is no functioning at all.

Version-Release number of selected component (if applicable):

parallel-20160722-3.fc26.noarch

How reproducible:

Always

Steps to Reproduce:
1. niceload -n 2 sleep 30
2.
3.

Actual results:

In Fedora 27:
---
Unescaped left brace in regex is illegal here in regex; marked by <-- HERE in m/vm\.loadavg: { <-- HERE  ([0-9.]+) ([0-9.]+) ([0-9.]+) }/ at /usr/bin/niceload line 1022.
(exit and error)
---


In Fedora 26:
---
Unescaped left brace in regex is deprecated, passed through in regex; marked by <-- HERE in m/vm\.loadavg: { <-- HERE  ([0-9.]+) ([0-9.]+) ([0-9.]+) }/ at /usr/bin/niceload line 1022.
(and the command runs)
---

This is due to a literal { in a regular expressions being deprecated since perl 5.22 and simply flagged as errors
from perl 5.26. F26 has 5.24, while F27 has 5.26.

Expected results:

Function as described in the man page.

Additional info:

I guess two options ...

*) Quick fix:

Edit line 1022 and escape the left brace with a backslash:

---------------------------
--- /usr/bin/niceload.orig      2017-12-04 09:58:56.968454067 +0100
+++ /usr/bin/niceload   2017-12-04 09:59:15.182548403 +0100
@@ -1019,7 +1019,7 @@
 
 sub load_status_darwin {
     my $loadavg = `sysctl vm.loadavg`;
-    if($loadavg =~ /vm\.loadavg: { ([0-9.]+) ([0-9.]+) ([0-9.]+) }/) {
+    if($loadavg =~ /vm\.loadavg: \{ ([0-9.]+) ([0-9.]+) ([0-9.]+) }/) {
        $loadavg = $1;
     } elsif (open(IN,"LANG=C uptime|")) {
        my $upString = <IN>;
--------------------------

*) Other fix:

Update to upstream version parallel-20170206.