bin/prioritize-build-list: do not write to input if it is a pipe

1 files changed, 2 insertions, 1 deletions

diff --git a/bin/prioritize-build-list b/bin/prioritize-build-list
index 87450e3..f68a559 100755
--- a/bin/prioritize-build-list
+++ b/bin/prioritize-build-list
@@ -92,7 +92,8 @@ verbose_flock ${wait_for_lock} 8
   printf 'SELECT row_count();\n'
 } | \
   mysql_run_query | \
-  if [ -w "$1" ]; then
+  if [ -w "$1" ] && \
+    [ ! -p "$1" ]; then
     cat > "$1"
   else
     cat >&2