showbuildenv: Add comment describing exit-status convention.

It helps explain why some commands are `... || true' despite no `set -e'
being in effect.

diff --git a/tools/showbuildenv b/tools/showbuildenv
index 2338bc6ce59958538ee113cd5e9a8e3a42f954af..81f278e86bd257b0a951c56738aa9616ac3fb926 100755 (executable)
--- a/tools/showbuildenv
+++ b/tools/showbuildenv
@@ -9,6 +9,10 @@
 # This script should *only* report basic information about the build
 # environment, and only that necessary to reproduce the build
 # environment.
 # This script should *only* report basic information about the build
 # environment, and only that necessary to reproduce the build
 # environment.

+#
+# The script's exit status must be zero if all went acceptably well as
+# buildbot checks for this and marks the `environment' stage as failed
+# otherwise.

 
 offset () {
     sed -e '/./s/^/    /' "$@"
 
 offset () {
     sed -e '/./s/^/    /' "$@"