Rename HOSTNAME variable to TARGET_HOSTNAME

Bash sets the HOSTNAME variable, overriding our default

README.md

@@ -82,7 +82,7 @@ The following environment variables are supported:
 
    Default system locale.
 
- * `HOSTNAME` (Default: "raspberrypi" )
+ * `TARGET_HOSTNAME` (Default: "raspberrypi" )
 
    Setting the hostname to the specified value.
 

build.sh

@@ -162,7 +162,7 @@ export DEPLOY_DIR=${DEPLOY_DIR:-"${BASE_DIR}/deploy"}
 export DEPLOY_ZIP="${DEPLOY_ZIP:-1}"
 export LOG_FILE="${WORK_DIR}/build.log"
 
-export HOSTNAME=${HOSTNAME:-raspberrypi}
+export TARGET_HOSTNAME=${TARGET_HOSTNAME:-raspberrypi}
 
 export FIRST_USER_NAME=${FIRST_USER_NAME:-pi}
 export FIRST_USER_PASS=${FIRST_USER_PASS:-raspberry}

stage1/02-net-tweaks/00-run.sh

@@ -1,6 +1,6 @@
 #!/bin/bash -e
 
-echo "${HOSTNAME}" > "${ROOTFS_DIR}/etc/hostname"
-echo "127.0.1.1		${HOSTNAME}" >> "${ROOTFS_DIR}/etc/hosts"
+echo "${TARGET_HOSTNAME}" > "${ROOTFS_DIR}/etc/hostname"
+echo "127.0.1.1		${TARGET_HOSTNAME}" >> "${ROOTFS_DIR}/etc/hosts"
 
 ln -sf /dev/null "${ROOTFS_DIR}/etc/systemd/network/99-default.link"