update docs

Docker-DCO-1.1-Signed-off-by: Victor Vieux <vieux@docker.com> (github: vieux)

api/client/commands.go

@@ -1693,7 +1693,7 @@ func (cli *DockerCli) CmdLogs(args ...string) error {
 		cmd    = cli.Subcmd("logs", "CONTAINER", "Fetch the logs of a container")
 		follow = cmd.Bool([]string{"f", "-follow"}, false, "Follow log output")
 		times  = cmd.Bool([]string{"t", "-timestamps"}, false, "Show timestamps")
-		tail   = cmd.String([]string{"-tail"}, "all", "Output the specified number of lines at the end of logs(all logs by default)")
+		tail   = cmd.String([]string{"-tail"}, "all", "Output the specified number of lines at the end of logs (defaults to all logs)")
 	)
 
 	if err := cmd.Parse(args); err != nil {

docs/sources/reference/commandline/cli.md

@@ -738,15 +738,15 @@ specify this by adding the server name.
 
       -f, --follow=false        Follow log output
       -t, --timestamps=false    Show timestamps
-      --tail="all"              Output the specified number of lines at the end of logs (all logs by default)
+      --tail="all"              Output the specified number of lines at the end of logs (defaults to all logs)
 
 The `docker logs` command batch-retrieves logs present at the time of execution.
 
 The `docker logs --follow` command will continue streaming the new output from
 the container's `STDOUT` and `STDERR`.
 
-Passing a negative number or a non-integer to --tail is invalid and the
-value is set to all in that case. This behavior may change in the future.
+Passing a negative number or a non-integer to `--tail` is invalid and the
+value is set to `all` in that case. This behavior may change in the future.
 
 ## port