a2b529ead2
--help and help are successful commands so output should not go to error.
QE teams have requested this change, also users doing docker help | less
or docker run --help | less would expect this to work.
Usage statement should only be printed when the user asks for it.
Errors should print error message and then suggest the docker COMMAND --help
command to see usage information.
The current behaviour causes the user to have to search for the error message
and sometimes scrolls right off the screen. For example a error on a
"docker run" command is very difficult to diagnose.
Finally erros should always exit with a non 0 exit code, if the user
makes a CLI error.
Docker-DCO-1.1-Signed-off-by: Dan Walsh <dwalsh@redhat.com> (github: rhatdan)
1.1 KiB
% DOCKER(1) Docker User Manuals % Docker Community % JUNE 2014
NAME
docker-save - Save an image(s) to a tar archive (streamed to STDOUT by default)
SYNOPSIS
docker save [--help] [-o|--output[=OUTPUT]] IMAGE [IMAGE...]
DESCRIPTION
Produces a tarred repository to the standard output stream. Contains all parent layers, and all tags + versions, or specified repo:tag.
Stream to a file instead of STDOUT by using -o.
OPTIONS
--help Print usage statement
-o, --output="" Write to a file, instead of STDOUT
EXAMPLES
Save all fedora repository images to a fedora-all.tar and save the latest fedora image to a fedora-latest.tar:
$ sudo docker save fedora > fedora-all.tar
$ sudo docker save --output=fedora-latest.tar fedora:latest
$ ls -sh fedora-all.tar
721M fedora-all.tar
$ ls -sh fedora-latest.tar
367M fedora-latest.tar
HISTORY
April 2014, Originally compiled by William Henry (whenry at redhat dot com) based on docker.com source material and internal work. June 2014, updated by Sven Dowideit SvenDowideit@home.org.au November 2014, updated by Sven Dowideit SvenDowideit@home.org.au