ARM build script: more reliable detection of completion.

Previously we downloaded the tar.gz before it was complete.

linux/make_artifacts.sh

@@ -11,6 +11,13 @@ esac
 
 ARTIFACTS="${ARTIFACTS:-/artifacts}"
 
+rm $ARTIFACTS/*
+
+clean_up() {
+  echo "All done!" > "$ARTIFACTS/DONE"
+}
+trap clean_up EXIT
+
 # build binaries
 
 cabal --version
@@ -72,3 +79,5 @@ gzip -9 $TARGET/share/man/man1/pandoc.1
 
 tar cvzf $TARGET-linux-$ARCHITECTURE.tar.gz $TARGET
 rm -r $TARGET
+
+exit 0

tools/build-arm.sh

@@ -86,7 +86,7 @@ do
   # print last line of log output and free memory
   $SSH "tail -n1 src/pandoc/docker.log && free -h | grep Mem"
   # Check to see if the artifact has been produced
-  $SSH "ls -l src/pandoc/linux/artifacts/*.tar.gz 2>/dev/null" && break
+  $SSH "ls -l src/pandoc/linux/artifacts/DONE 2>/dev/null" && break
 done
 
 # Retrieve the artifacts