diff -r 2c0ed9ec9a8c -r 2535545dd450 docs/overview.txt
--- a/docs/overview.txt	Thu Feb 11 21:28:10 2010 +0100
+++ b/docs/overview.txt	Fri Mar 05 09:19:56 2010 +0100
@@ -21,6 +21,7 @@
 Configuring crosstool-NG
   Interesting config options
   Re-building an existing toolchain
+  Using as a backend for a build-system
 Running crosstool-NG
   Stopping and restarting a build
   Testing all toolchains at once
@@ -350,6 +351,21 @@
 Then, you can review and change the configuration by running:
   ct-ng menuconfig
 
+Using as a backend for a build-system |
+--------------------------------------+
+
+Crosstool-NG can be used as a backend for an automated build-system. In this
+case, some components that are expected to run on the target (eg. the native
+gdb, ltrace, DUMA...) are not available in the menuconfig, and they are not
+build either, as it is considered the responsibility of the build-system to
+build its own versions of those tools.
+
+If you want to use crosstool-NG as a backend to generate your toolchains for
+your build-system, you have to set and export this environment variable:
+  CT_IS_A_BACKEND=y
+
+(case is not sensitive, you can say Y).
+
 
 ________________________
                        /