5 files changed, 17 insertions, 4 deletions
diff --git a/runsc/cmd/boot.go b/runsc/cmd/boot.go
index d26e92bcd..023b63dc0 100644
--- a/runsc/cmd/boot.go
+++ b/runsc/cmd/boot.go
@@ -66,6 +66,9 @@ type Boot struct {
 	// totalMem sets the initial amount of total memory to report back to the
 	// container.
 	totalMem uint64
+
+	// userLogFD is the file descriptor to write user logs to.
+	userLogFD int
 }
 
 // Name implements subcommands.Command.Name.
@@ -95,6 +98,7 @@ func (b *Boot) SetFlags(f *flag.FlagSet) {
 	f.BoolVar(&b.applyCaps, "apply-caps", false, "if true, apply capabilities defined in the spec to the process")
 	f.IntVar(&b.cpuNum, "cpu-num", 0, "number of CPUs to create inside the sandbox")
 	f.Uint64Var(&b.totalMem, "total-memory", 0, "sets the initial amount of total memory to report back to the container")
+	f.IntVar(&b.userLogFD, "user-log-fd", 0, "file descriptor to write user logs to. 0 means no logging.")
 }
 
 // Execute implements subcommands.Command.Execute.  It starts a sandbox in a
@@ -163,6 +167,7 @@ func (b *Boot) Execute(_ context.Context, f *flag.FlagSet, args ...interface{})
 		Console:      b.console,
 		NumCPU:       b.cpuNum,
 		TotalMem:     b.totalMem,
+		UserLogFD:    b.userLogFD,
 	}
 	l, err := boot.New(bootArgs)
 	if err != nil {
diff --git a/runsc/cmd/capability_test.go b/runsc/cmd/capability_test.go
index be9ef2e7b..3329b308d 100644
--- a/runsc/cmd/capability_test.go
+++ b/runsc/cmd/capability_test.go
@@ -97,7 +97,7 @@ func TestCapabilities(t *testing.T) {
 	defer os.RemoveAll(bundleDir)
 
 	// Create and start the container.
-	c, err := container.Create(testutil.UniqueContainerID(), spec, conf, bundleDir, "", "")
+	c, err := container.Create(testutil.UniqueContainerID(), spec, conf, bundleDir, "", "", "")
 	if err != nil {
 		t.Fatalf("error creating container: %v", err)
 	}
diff --git a/runsc/cmd/checkpoint.go b/runsc/cmd/checkpoint.go
index d074b8617..023ab2455 100644
--- a/runsc/cmd/checkpoint.go
+++ b/runsc/cmd/checkpoint.go
@@ -133,7 +133,7 @@ func (c *Checkpoint) Execute(_ context.Context, f *flag.FlagSet, args ...interfa
 		Fatalf("error destroying container: %v", err)
 	}
 
-	cont, err = container.Create(id, spec, conf, bundleDir, "", "")
+	cont, err = container.Create(id, spec, conf, bundleDir, "", "", "")
 	if err != nil {
 		Fatalf("error restoring container: %v", err)
 	}
diff --git a/runsc/cmd/create.go b/runsc/cmd/create.go
index 38ae03e7a..ecd76ee93 100644
--- a/runsc/cmd/create.go
+++ b/runsc/cmd/create.go
@@ -41,6 +41,13 @@ type Create struct {
 	// pseudoterminal.  This is ignored unless spec.Process.Terminal is
 	// true.
 	consoleSocket string
+
+	// userLog is the path to send user-visible logs to. This log is different
+	// from debug logs. The former is meant to be consumed by the users and should
+	// contain only information that is relevant to the person running the
+	// container, e.g. unsuported syscalls, while the later is more verbose and
+	// consumed by developers.
+	userLog string
 }
 
 // Name implements subcommands.Command.Name.
@@ -64,6 +71,7 @@ func (c *Create) SetFlags(f *flag.FlagSet) {
 	f.StringVar(&c.bundleDir, "bundle", "", "path to the root of the bundle directory, defaults to the current directory")
 	f.StringVar(&c.consoleSocket, "console-socket", "", "path to an AF_UNIX socket which will receive a file descriptor referencing the master end of the console's pseudoterminal")
 	f.StringVar(&c.pidFile, "pid-file", "", "filename that the container pid will be written to")
+	f.StringVar(&c.userLog, "user-log", "", "filename to send user-visible logs to. Empty means no logging.")
 }
 
 // Execute implements subcommands.Command.Execute.
@@ -90,7 +98,7 @@ func (c *Create) Execute(_ context.Context, f *flag.FlagSet, args ...interface{}
 	// Create the container. A new sandbox will be created for the
 	// container unless the metadata specifies that it should be run in an
 	// existing container.
-	if _, err := container.Create(id, spec, conf, bundleDir, c.consoleSocket, c.pidFile); err != nil {
+	if _, err := container.Create(id, spec, conf, bundleDir, c.consoleSocket, c.pidFile, c.userLog); err != nil {
 		Fatalf("error creating container: %v", err)
 	}
 	return subcommands.ExitSuccess
diff --git a/runsc/cmd/run.go b/runsc/cmd/run.go
index 92aa6bc40..826e6e875 100644
--- a/runsc/cmd/run.go
+++ b/runsc/cmd/run.go
@@ -75,7 +75,7 @@ func (r *Run) Execute(_ context.Context, f *flag.FlagSet, args ...interface{}) s
 	specutils.LogSpec(spec)
 	conf.SpecFile = filepath.Join(bundleDir, "config.json")
 
-	ws, err := container.Run(id, spec, conf, bundleDir, r.consoleSocket, r.pidFile)
+	ws, err := container.Run(id, spec, conf, bundleDir, r.consoleSocket, r.pidFile, r.userLog)
 	if err != nil {
 		Fatalf("error running container: %v", err)
 	}