docs: clarify custom build output directory in PCbuild/readme.txt

pranavchoudhary-tech · pranavchoudhary-tech · commit dfd26ac04486 · 2026-07-09T10:32:19.000+05:30
diff --git a/PCbuild/readme.txt b/PCbuild/readme.txt
@@ -105,6 +105,17 @@ the 32-bit Win32 platform.  It accepts several arguments to change
 this behavior, try `build.bat -h` to learn more.
 
 
+Custom Output Directory
+-----------------------
+
+If you want to move the build outputs to a different directory, do not use the standard MSBuild `/p:OutDir=` property, as CPython has many assumptions about where the source repository is relative to the built files. 
+Instead, you can override the output directory by setting `Py_OutDir` (for example, `build.bat "/p:Py_OutDir=C:\MyOutput"`). 
+
+However, be aware that the compiled binaries probably won't run directly from that location. If you want to make an install-shaped layout without creating the installer, build CPython normally first, and then use the `PC/layout` script with the runtime you just built:
+    python.bat PC/layout --<options>
+Use `-h` with that command to see all available options for customizing the layout.
+
+
 C Runtime
 ---------
 
