Documenting the export-host-variables.sh

scripts/export-host-variables.sh

@@ -1,5 +1,6 @@
 # Defining a toolchain directory's name according to the current OS.
-# Assume that proper version of NDK is installed.
+# Assume that proper version of NDK is installed
+# and is referenced by ANDROID_NDK_HOME environment variable
 case "$OSTYPE" in
   darwin*)  HOST_TAG="darwin-x86_64" ;;
   linux*)   HOST_TAG="linux-x86_64" ;;
@@ -17,5 +18,7 @@ else
   HOST_NPROC=$(nproc)
 fi
 
+# The variable is used as a path segment of the toolchain path
 export HOST_TAG=$HOST_TAG
+# Number of physical cores in the system to facilitate parallel assembling
 export HOST_NPROC=$HOST_NPROC