Default --sig-proxy to true for 'podman start --attach'

The --sig-proxy option in both 'podman attach' and 'podman run' default
to true, and there's no reason for 'podman start --attach' to be any
different. However, since it only makes sense to proxy signals when
the container is attached, 'podman start --sig-proxy' will continue to
error if --attach isn't used.

Signed-off-by: Debarshi Ray <rishi@fedoraproject.org>

2 files changed, 12 insertions, 6 deletions

diff --git a/cmd/podman/start.go b/cmd/podman/start.go
index 8bb386c68..df34deec2 100644
--- a/cmd/podman/start.go
+++ b/cmd/podman/start.go
@@ -27,9 +27,9 @@ var (
 			Name:  "interactive, i",
 			Usage: "Keep STDIN open even if not attached",
 		},
-		cli.BoolFlag{
+		cli.BoolTFlag{
 			Name:  "sig-proxy",
-			Usage: "proxy received signals to the process",
+			Usage: "proxy received signals to the process (default true if attaching, false otherwise)",
 		},
 		LatestFlag,
 	}
@@ -67,8 +67,14 @@ func startCmd(c *cli.Context) error {
 		return err
 	}
 
-	if c.Bool("sig-proxy") && !attach {
-		return errors.Wrapf(libpod.ErrInvalidArg, "you cannot use sig-proxy without --attach")
+	sigProxy := c.BoolT("sig-proxy")
+
+	if sigProxy && !attach {
+		if c.IsSet("sig-proxy") {
+			return errors.Wrapf(libpod.ErrInvalidArg, "you cannot use sig-proxy without --attach")
+		} else {
+			sigProxy = false
+		}
 	}
 
 	runtime, err := libpodruntime.GetRuntime(c)
@@ -111,7 +117,7 @@ func startCmd(c *cli.Context) error {
 			}
 
 			// attach to the container and also start it not already running
-			err = startAttachCtr(ctr, os.Stdout, os.Stderr, inputStream, c.String("detach-keys"), c.Bool("sig-proxy"), !ctrRunning)
+			err = startAttachCtr(ctr, os.Stdout, os.Stderr, inputStream, c.String("detach-keys"), sigProxy, !ctrRunning)
 			if ctrRunning {
 				return err
 			}
diff --git a/docs/podman-start.1.md b/docs/podman-start.1.md
index cfd44ac3a..f16a20efa 100644
--- a/docs/podman-start.1.md
+++ b/docs/podman-start.1.md
@@ -35,7 +35,7 @@ to run containers such as CRI-O, the last started container could be from either
 
 **--sig-proxy**=*true*|*false*
 
-Proxy received signals to the process (non-TTY mode only). SIGCHLD, SIGSTOP, and SIGKILL are not proxied. The default is false.
+Proxy received signals to the process (non-TTY mode only). SIGCHLD, SIGSTOP, and SIGKILL are not proxied. The default is *true* when attaching, *false* otherwise.
 
 ## EXAMPLE