update readme

README.md

@@ -5,7 +5,7 @@
 [ZeroTier One](https://www.zerotier.com) is a programm to create a global provider-independent virtual private cloud.
 This project offers OpenWrt packages for ZeroTier.
 
-## Installing prebuild package
+## Installing package
 
 Download the [prebuild package](https://github.com/mwarning/zerotier-openwrt/releases) and copy it onto your OpenWrt installation, preferably into the /tmp folder.
 Then install the ipk package file:
@@ -41,7 +41,9 @@ cd openwrt
 
 Now you can insert the zerotier package using a package feed or add the package manually.
 
-### Using a package feed
+### Add package by feed
+
+A feed is the standard way packages are made available to the OpenWrt build system.
 
 Put this line in your feeds list file (e.g. feeds.conf.default)
 ```
@@ -71,7 +73,6 @@ Now continue with the building packages section.
 Configure packages:
 
 ```
-make defconfig
 make menuconfig
 ```
 
@@ -89,3 +90,34 @@ The images and all *.ipk packages are now inside the bin/ folder, including the
 You can install the ZeroTier .ipk on the target device using "opkg install \<ipkg-file\>".
 
 For details please check the OpenWrt documentation.
+
+#### Build bulk packages
+
+For a release, it is useful the build packages at a bulk for multiple targets:
+
+```
+#!/bin/sh
+
+targets='
+	CONFIG_TARGET_arm64=y
+	CONFIG_TARGET_ath25=y
+'
+
+for target in $targets; do
+	echo "$target" > .config
+	echo "CONFIG_PACKAGE_zerotier=y" >> .config
+
+	# Debug output
+	echo "Build: $target"
+
+	# Build toolchain and package
+	make defconfig
+	make tools/install
+	make toolchain/install
+	make package/zerotier/{clean,compile} V=s
+
+	# Free space
+	rm -rf build_dir/target-*
+	rm -rf build_dir/toolchain-*
+done
+```