File: engine/reference/builder.md

These points relate to https://docs.docker.com/engine/reference/builder/#shell-form-entrypoint-example. Several points:

1. The following Dockerfile does not build:

FROM ubuntu
ENTRYPOINT top -b
CMD --ignored-param1

# docker build -t top .
Sending build context to Docker daemon  70.14kB
Error response from daemon: Dockerfile parse error line 6: Unknown flag: ignored-param1
#

2. command output conflicts with argument(s?) to docker run in the example given:

$ docker run -it --name test top --ignored-param2

Mem: 1704184K used, 352484K free, 0K shrd, 0K buff, 140621524238337K cached
CPU:   9% usr   2% sys   0% nic  88% idle   0% io   0% irq   0% sirq
Load average: 0.01 0.02 0.05 2/101 7
  PID  PPID USER     STAT   VSZ %VSZ %CPU COMMAND
    1     0 root     S     3168   0%   0% /bin/sh -c top -b cmd cmd2
    7     1 root     R     3164   0%   0% top -b

Command gives --ignored-param2, while output uses cmd cmd2. This is besides the fact that the container's output from top does not reveal the command line arguments for both sh and top; you need to use docker top test for that.

3. The table at https://docs.docker.com/engine/reference/builder/#understand-how-cmd-and-entrypoint-interact needs to be updated. Specifically the ENTRYPOINT exec_entry p1_entry, with CMD exec_cmd p1_cmd entry. I get /bin/sh -c exec_entry p1_entry sh -c exec_cmd p1_cmd

# docker version
Client: Docker Engine - Community
 Version:           19.03.12
 API version:       1.40
 Go version:        go1.13.10
 Git commit:        48a66213fe
 Built:             Mon Jun 22 15:45:44 2020
 OS/Arch:           linux/amd64
 Experimental:      false

Server: Docker Engine - Community
 Engine:
  Version:          19.03.12
  API version:      1.40 (minimum version 1.12)
  Go version:       go1.13.10
  Git commit:       48a66213fe
  Built:            Mon Jun 22 15:44:15 2020
  OS/Arch:          linux/amd64
  Experimental:     false
 containerd:
  Version:          1.2.13
  GitCommit:        7ad184331fa3e55e52b890ea95e65ba581ae3429
 runc:
  Version:          1.0.0-rc10
  GitCommit:        dc9208a3303feef5b3839f4323d9beb36df0a9dd
 docker-init:
  Version:          0.18.0
  GitCommit:        fec3683