3 files changed, 9 insertions, 5 deletions
diff --git a/bin/sh/eval.c b/bin/sh/eval.c
index 25c3fcf..14dd15f 100644
--- a/bin/sh/eval.c
+++ b/bin/sh/eval.c
@@ -997,8 +997,7 @@ evalcommand(union node *cmd, int flags, struct backcmd *backcmd)
 		 */
 		if (argc == 0 && !(flags & EV_BACKCMD))
 			cmdentry.special = 1;
-		if (cmdentry.special)
-			listsetvar(cmdenviron);
+		listsetvar(cmdenviron, cmdentry.special ? 0 : VNOSET);
 		if (argc > 0)
 			bltinsetlocale();
 		commandname = argv[0];
diff --git a/bin/sh/var.c b/bin/sh/var.c
index 6c0618f..e841647 100644
--- a/bin/sh/var.c
+++ b/bin/sh/var.c
@@ -333,6 +333,8 @@ setvareq(char *s, int flags)
 				len = strchr(s, '=') - s;
 				error("%.*s: is read only", len, s);
 			}
+			if (flags & VNOSET)
+				return;
 			INTOFF;
 
 			if (vp->func && (flags & VNOFUNC) == 0)
@@ -365,6 +367,8 @@ setvareq(char *s, int flags)
 		}
 	}
 	/* not found */
+	if (flags & VNOSET)
+		return;
 	vp = ckmalloc(sizeof (*vp));
 	vp->flags = flags;
 	vp->text = s;
@@ -386,13 +390,13 @@ setvareq(char *s, int flags)
  */
 
 void
-listsetvar(struct strlist *list)
+listsetvar(struct strlist *list, int flags)
 {
 	struct strlist *lp;
 
 	INTOFF;
 	for (lp = list ; lp ; lp = lp->next) {
-		setvareq(savestr(lp->text), 0);
+		setvareq(savestr(lp->text), flags);
 	}
 	INTON;
 }
diff --git a/bin/sh/var.h b/bin/sh/var.h
index 1ec707b..775db41 100644
--- a/bin/sh/var.h
+++ b/bin/sh/var.h
@@ -45,6 +45,7 @@
 #define VSTACK		0x10	/* text is allocated on the stack */
 #define VUNSET		0x20	/* the variable is not set */
 #define VNOFUNC		0x40	/* don't call the callback function */
+#define VNOSET		0x80	/* do not set variable - just readonly test */
 
 
 struct var {
@@ -106,7 +107,7 @@ void initvar(void);
 void setvar(const char *, const char *, int);
 void setvareq(char *, int);
 struct strlist;
-void listsetvar(struct strlist *);
+void listsetvar(struct strlist *, int);
 char *lookupvar(const char *);
 char *bltinlookup(const char *, int);
 void bltinsetlocale(void);