diff --git a/mach/proto/mcg/mcg.h b/mach/proto/mcg/mcg.h
index 9991d5001..69f194e85 100644
--- a/mach/proto/mcg/mcg.h
+++ b/mach/proto/mcg/mcg.h
@@ -79,7 +79,6 @@ struct em
     } u;
 };
     
-extern const char* aprintf(const char* fmt, ...);
 extern void tracef(char k, const char* fmt, ...);
 extern bool tracing(char k);
 
diff --git a/modules/src/data/astring.c b/modules/src/data/astring.c
index 7da06e9fa..097d9f4ad 100644
--- a/modules/src/data/astring.c
+++ b/modules/src/data/astring.c
@@ -2,7 +2,7 @@
 #include <stdlib.h>
 #include <stdarg.h>
 
-const char* aprintf(const char* fmt, ...)
+char* aprintf(const char* fmt, ...)
 {
     int n;
     char* p;
diff --git a/modules/src/data/astring.h b/modules/src/data/astring.h
index 483c0287d..d1fffa807 100644
--- a/modules/src/data/astring.h
+++ b/modules/src/data/astring.h
@@ -1,7 +1,7 @@
 #ifndef ASTRING_H
 #define ASTRING_H
 
-extern const char* aprintf(const char* fmt, ...);
+extern char* aprintf(const char* fmt, ...);
 
 #endif
 
diff --git a/modules/src/system/aprintf.c b/modules/src/system/aprintf.c
deleted file mode 100644
index 997d408c2..000000000
--- a/modules/src/system/aprintf.c
+++ /dev/null
@@ -1,28 +0,0 @@
-#include <stdio.h>
-#include <stdlib.h>
-#include <stdarg.h>
-#include "system.h"
-
-char* aprintf(const char* fmt, ...)
-{
-    int n;
-    char* p;
-    va_list ap;
-
-    va_start(ap, fmt);
-    n = vsnprintf(NULL, 0, fmt, ap) + 1;
-    va_end(ap);
-
-    p = malloc(n);
-    if (!p)
-        return NULL;
-
-    va_start(ap, fmt);
-    vsnprintf(p, n, fmt, ap);
-    va_end(ap);
-
-    return p;
-}
-
-/* vim: set sw=4 ts=4 expandtab : */
-
diff --git a/modules/src/system/build.lua b/modules/src/system/build.lua
index c19a82924..500cd59f2 100644
--- a/modules/src/system/build.lua
+++ b/modules/src/system/build.lua
@@ -2,7 +2,6 @@ clibrary {
 	name = "lib",
 	srcs = {
 		"./access.c",
-		"./aprintf.c",
 		"./basename.c",
 		"./break.c",
 		"./chmode.c",
@@ -27,4 +26,7 @@ clibrary {
 		--"./unlock.c”,
 	},
 	hdrs = { "./system.h" },
+	deps = {
+		"modules/src/data+lib",
+	}
 }
diff --git a/modules/src/system/maketempfile.c b/modules/src/system/maketempfile.c
index 02068b628..83accf8f9 100644
--- a/modules/src/system/maketempfile.c
+++ b/modules/src/system/maketempfile.c
@@ -7,6 +7,7 @@
 #include <fcntl.h>
 #include <errno.h>
 #include "system.h"
+#include "astring.h"
 
 #if defined WIN32
 static unsigned temper(unsigned x)
@@ -20,7 +21,8 @@ static unsigned temper(unsigned x)
 
 static int rand_r(unsigned *seed)
 {
-	return temper(*seed = *seed * 1103515245 + 12345)/2;
+	*seed = *seed * 1103515245 + 12345;
+	return temper(*seed)/2;
 }
 #endif
 
@@ -36,8 +38,9 @@ char* sys_maketempfile(const char* prefix, const char* suffix)
 	for (;;)
 	{
 		unsigned int hash = rand_r(&seed);
-		char* filename = aprintf("%s/ack-%s-%x%s",
+		char* filename = aprintf("%s/ack.%s-%x%s%s",
 			tempdir, prefix, hash,
+			((*suffix == 0) || (*suffix == '.')) ? "" : ".",
 			suffix);
 		int fd = open(filename, O_CREAT|O_EXCL|O_RDWR, 0600);
 		if (fd != -1)
diff --git a/util/ack/build.lua b/util/ack/build.lua
index cf4dc9035..cd865332b 100644
--- a/util/ack/build.lua
+++ b/util/ack/build.lua
@@ -34,6 +34,7 @@ cprogram {
 	deps = {
 		"h+emheaders",
 		"h+local",
+		"modules/src/data+lib",
 		"modules/src/system+lib",
 		"./ack.h",
 		"./data.h",
diff --git a/util/arch/build.lua b/util/arch/build.lua
index 160b9c21f..eff8e22ad 100644
--- a/util/arch/build.lua
+++ b/util/arch/build.lua
@@ -3,6 +3,7 @@ cprogram {
 	srcs = { "./archiver.c" },
 	deps = {
 		"h+emheaders",
+		"modules/src/data+lib",
 		"modules/src/object+lib",
 		"modules/src/print+lib",
 		"modules/src/string+lib",
diff --git a/util/ass/build.lua b/util/ass/build.lua
index d976e1bf0..f46668cc8 100644
--- a/util/ass/build.lua
+++ b/util/ass/build.lua
@@ -44,7 +44,7 @@ cprogram {
 		"h+local",
 		--"modules/src/alloc+lib",
 		"modules/src/em_data+lib",
-		--"modules/src/data+lib",
+		"modules/src/data+lib",
 		--"modules/src/object+lib",
 		"modules/src/system+lib",
 		"./ass00.h",
diff --git a/util/ego/build.lua b/util/ego/build.lua
index 5d7768e7e..8749fe40d 100644
--- a/util/ego/build.lua
+++ b/util/ego/build.lua
@@ -40,6 +40,7 @@ cprogram {
 		"./ca/ca_put.h",
 		"util/ego/share+lib",
 		"modules/src/em_data+lib",
+		"modules/src/data+lib",
 		"modules/src/system+lib",
 		"h+emheaders",
 	},
@@ -177,6 +178,7 @@ cprogram {
 		"./il/il.h",
 		"util/ego/share+lib",
 		"modules/src/em_data+lib",
+		"modules/src/data+lib",
 		"modules/src/system+lib",
 		"h+emheaders",
 	},
@@ -275,6 +277,7 @@ cprogram {
 		"modules/src/print+lib",
 		"modules/src/string+lib",
 		"modules/src/system+lib",
+		"modules/src/data+lib",
 		"modules+headers",
 		"h+emheaders",
 	}
diff --git a/util/opt/build.lua b/util/opt/build.lua
index d62858042..ec213d879 100644
--- a/util/opt/build.lua
+++ b/util/opt/build.lua
@@ -84,6 +84,7 @@ local function variant(name, cflags)
 			"modules/src/print+lib",
 			"modules/src/string+lib",
 			"modules/src/system+lib",
+			"modules/src/data+lib",
 			"modules/src/em_data+lib"
 		),
 		vars = {