os/exec: dump lsof on failure

R=golang-dev, bradfitz
CC=golang-dev
https://golang.org/cl/5504063

diff --git a/src/pkg/os/exec/exec_test.go b/src/pkg/os/exec/exec_test.go
index a015cbe96cc051d541bd718d9e28713e9bd45785..d7e61e73795cc5fd0084f47d1525a51fdf6f0981 100644 (file)
--- a/src/pkg/os/exec/exec_test.go
+++ b/src/pkg/os/exec/exec_test.go
@@ -262,6 +262,7 @@ func TestHelperProcess(*testing.T) {
                        f, err := os.Open(os.Args[0])
                        if err != nil {
                                fmt.Printf("error opening file with expected fd %d: %v", wantfd, err)
+                               fmt.Println(Command("lsof", "-p", fmt.Sprint(os.Getpid())).CombinedOutput())
                                os.Exit(1)
                        }
                        if got := f.Fd(); got != wantfd {