diff --git a/README.md b/README.md
index 8b4b466..ce72a73 100644
--- a/README.md
+++ b/README.md
@@ -13,7 +13,7 @@ This wrapper renders `dc` more usable as a command line calculator by:
 - defining commonly used macros for more complex operations
 - saving precision, top of stack, and registers 0 to 9 ("memories")
   from one invocation to the next in the status file `$HOME/.wdcrc`
-- saving last top of stack value in `/tmp/wdc-$USER` for further direct use
+- saving last top of stack value in `${TMPDIR:-/tmp}/wdc-$USER` for further direct use
   (change file name in the source, if desired)
 
 # PREREQUISITES
diff --git a/wrapdc.sh b/wrapdc.sh
index 8b4ec19..b6db4a7 100755
--- a/wrapdc.sh
+++ b/wrapdc.sh
@@ -1,10 +1,10 @@
 #!/bin/sh
 # wrapper for dc
-info="wrapper for dc // 2017-03-10 Y.Bonetti // see https://gitlab.com/yargo/wrapdc"
+info="wrapper for dc // 2017-08-31 Y.Bonetti // see https://gitlab.com/yargo/wrapdc"
 # global status file
 statf=$HOME/.wdcrc
 # output file (last stack top)
-outf=/tmp/wdc-$USER
+outf=${TMPDIR:-/tmp}/wdc-$USER
 # clear state: precision 2, clear stack and reg.0..9
 clstat='2k 0 0 0 0 0 0s00s10s20s30s40s50s60s70s80s9'
 if test ! -r $statf