add comments documenting what we do and make the script output all the build commands

build.sh

@@ -1,13 +1,32 @@
+#!/bin/bash
+
+# `.cpp` files in src/lib will be automatically picked up and compiled into dynamic libraries.
 echo "Building libs..."
 mkdir -pv bin/lib
 for lib in $(find ./src/lib -name "*.cpp"); do
-    echo "Compiling $lib"
-    c++ -shared -o $(sed -e 's/^.\/src/.\/bin/;s/cpp$/so/' <<< $lib) $lib;
+    COMPILE_COMMAND="c++ -shared -o $(sed -e 's/^.\/src/.\/bin/;s/cpp$/so/' <<< $lib) $lib"
+    echo $COMPILE_COMMAND
+    $COMPILE_COMMAND
 done
 
-echo "Building tools..."
-mkdir -pv bin/tools
+
 # Commands for every program need to be given individually because we can't
 # just add all shared libraries to all programs.
 # Or can we? Idk, cba to find out.
+
+# How to build a tool: Tell the compiler where to find shared libraries and
+#       which libraries to use.
+# Example: shared libraries are in bin/lib => -Lbin/lib
+#       one of the libraries in that directory is libnbt.so
+#        => use with -lnbt (omit prefix lib and suffix .so)
+# How to run a tool: specify the library path to use for the dynamic linker
+#       when running a program
+# Example: LD_LIBRARY_PATH=bin/lib bin/tools/dumpnbt
+echo "Building tools..."
+mkdir -pv bin/tools
+# add compile commands to this variable
+COMPILE_COMMANDS="
+set -v
 c++ src/tools/dumpnbt.cpp -Lbin/lib -lnbt -o bin/tools/dumpnbt
+"
+sh <<< $COMPILE_COMMANDS