add output file for last top of stack

README.md

@@ -13,6 +13,8 @@ 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 `$HOME/.wdcrc`
+- saving last top of stack value in `$HOME/wdc` for further direct use
+  (change file name in the source, if desired)
 
 # PREREQUISITES
 
@@ -160,8 +162,10 @@ only at the very end. Otherwise, e.g the `rem` command would first have its
 
 # FILES
 
-The status between invocations is stored in the file `$HOME/.wdcrc` as a
-list of `dc` commands.
+- The status between invocations is stored in the file `$HOME/.wdcrc` as a list of `dc` commands.
+- The last top of stack value is stored in `$HOME/wdc`.
+
+_These file names can be easily changed at the beginning of the script._
 
 # BUGS
 

wrapdc.sh

@@ -1,8 +1,10 @@
 #!/bin/sh
 # wrapper for dc
-info="wrapper for dc // 2016-11-22 Y.Bonetti // see https://gitlab.com/yargo/wrapdc"
+info="wrapper for dc // 2017-03-10 Y.Bonetti // see https://gitlab.com/yargo/wrapdc"
 # global status file
 statf=$HOME/.wdcrc
+# output file (last stack top)
+outf=$HOME/wdc
 # clear state: precision 2, clear stack and reg.0..9
 clstat='2k 0 0 0 0 0 0s00s10s20s30s40s50s60s70s80s9'
 if test ! -r $statf
@@ -112,6 +114,8 @@ LEl:x[
 # divide stack top by 10^A and print, print A
 lA10lAZLAX-1-sAlA^/n[E]nLAp
 ENDOFDCINPUT
+# save stack top in output file for further direct processing
+ tail -n 1 $statf | sed -e 's/ *#.*//' >$outf
 # print stack top
  tail -n 1 $statf
 }