Add warn-smtp-queue.

warn-smtp-queue

@@ -0,0 +1,31 @@
+#!/bin/bash
+
+# Source the mail configuration.
+source /etc/mail.conf "mail-queue" 2>/dev/null || {
+  printf "%s: %s\\n" "${0##*/}" "Failed to source /etc/mail.conf" >&2
+  exit 1
+}
+
+# Don't do anything unless 'mailq' is installed.
+hash mailq 2>/dev/null && {
+  # Prevent a race with other cron jobs that produce emails.
+  sleep $(( RANDOM % 180 ))
+
+  # Get the queue
+  TMP_OUTPUT="$(mailq)"
+
+  [[ -z "$TMP_OUTPUT" ]] && exit 0
+
+  # Send the message.
+  if [[ -n "${EMAIL_TO[*]}" ]]; then
+    mailx "${MAILX_ARGS[@]}" -S "from=$EMAIL_FROM" -s "Mail queue" "${EMAIL_TO[@]}" <<<"$TMP_OUTPUT" 2>/dev/null || {
+      printf "%s: %s\\n" "${0##*/}" "mailx command failed" >&2
+      exit 1
+    }
+  else
+    printf "%s: %s\\n" "${0##*/}" "no recipient configured for mail delivery" >&2
+    exit 1
+  fi
+}
+
+exit 0