From a9b0244e299fc912b073661f4e98c8379e96ea11 Mon Sep 17 00:00:00 2001
From: Simone Karin Lehmann <simone_lehmann@gothaer.de>
Date: Tue, 13 Mar 2018 22:29:56 +0100
Subject: [PATCH] fix the calculation again to be used by truncate. use
 truncate instead of dd. add build instructions for truncate to the helper
 script to build it on macOS

---
 make_e2fstools | 6 ++++++
 pishrink       | 6 ++----
 2 files changed, 8 insertions(+), 4 deletions(-)

diff --git a/make_e2fstools b/make_e2fstools
index 1f64521..d1cb213 100755
--- a/make_e2fstools
+++ b/make_e2fstools
@@ -43,5 +43,11 @@ cp -a e2fsck/e2fsck "$BASE"
 cp -a resize/resize2fs "$BASE"
 cp -a misc/tune2fs "$BASE"
 
+download https://ftp.gnu.org/gnu/coreutils/coreutils-8.29.tar.xz
+cd core*
+./configure --prefix "$TARGET" --disable-nls
+make
+cp -a src/truncate "$BASE"
+
 cd "$BASE"
 diskutil eject "/Volumes/Ramdisk"
diff --git a/pishrink b/pishrink
index e8e5168..13ce853 100755
--- a/pishrink
+++ b/pishrink
@@ -86,9 +86,7 @@ sleep 1
 #Truncate the file
 endresult=$(($newpartend * 512))
 endresult=$(($endresult + 1))
-dd if="$img" of="$img-shrinked.img" bs=512 count=$endresult
-aftersize=$(ls -lh "$img-shrinked.img" | tr -s " " | cut -d " " -f 5)
-rm -f "$img"
-mv "$img-shrinked.img" "$img"
+truncate -s $endresult "$img"
+aftersize=$(ls -lh "$img" | tr -s " " | cut -d " " -f 5)
 
 echo "Shrunk $img from $beforesize to $aftersize"