l: add untilport

lass/2configs/default.nix

@@ -112,6 +112,7 @@ with config.krebs.lib;
   #neat utils
     krebspaste
     psmisc
+    untilport
 
   #unpack stuff
     p7zip

lass/5pkgs/default.nix

@@ -10,6 +10,7 @@
     };
     mk_sql_pair = pkgs.callPackage ./mk_sql_pair/default.nix {};
     mpv-poll = pkgs.callPackage ./mpv-poll/default.nix {};
+    untilport = pkgs.callPackage ./untilport/default.nix {};
     urban = pkgs.callPackage ./urban/default.nix {};
     xmonad-lass =
       let src = pkgs.writeNixFromCabal "xmonad-lass.nix" ./xmonad-lass; in

lass/5pkgs/untilport/default.nix

@@ -0,0 +1,18 @@
+{ pkgs, ... }:
+
+pkgs.writeDashBin "untilport" ''
+  set -euf
+
+  usage() {
+    echo 'untiport $target $port'
+    echo 'Sleeps until the destinated port is reachable.'
+    echo 'ex: untilport google.de 80 && echo "google is now reachable"'
+  }
+
+
+  if [ $# -ne 2 ]; then
+    usage
+  else
+    until ${pkgs.netcat-openbsd}/bin/nc -z "$@"; do sleep 1; done
+  fi
+''