From 9167482d1275f2b17416ffcb18873237739f68c2 Mon Sep 17 00:00:00 2001
From: John Ericson <John.Ericson@Obsidian.Systems>
Date: Tue, 5 Nov 2019 19:19:14 -0500
Subject: [PATCH] opensp: `sgmlHookDone` can be undefined

---
 pkgs/tools/text/sgml/opensp/setup-hook.sh | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/pkgs/tools/text/sgml/opensp/setup-hook.sh b/pkgs/tools/text/sgml/opensp/setup-hook.sh
index 753a3ea64287..5bace3c66889 100644
--- a/pkgs/tools/text/sgml/opensp/setup-hook.sh
+++ b/pkgs/tools/text/sgml/opensp/setup-hook.sh
@@ -6,7 +6,7 @@ addSGMLCatalogs () {
       fi
 }
 
-if test -z "$sgmlHookDone"; then
+if test -z "${sgmlHookDone-}"; then
     sgmlHookDone=1
 
     # Set http_proxy and ftp_proxy to a invalid host to prevent