p4u1/docker-cli
0
0
Fork 0
Code Issues Pull Requests Actions Packages Projects Releases Wiki Activity

Make it clear who is doing variable expansion

Browse Source 
Add sentece to RUN, CMD, and ENTRYPOINT exec sections making it clear
that it is the shell doing the environment variable expansion.

Signed-off-by: David Dooling <dooling@gmail.com>
Upstream-commit: e6c152e5ee
Component: cli
This commit is contained in:
David Dooling
2016-08-17 06:31:19 -05:00
committed by Tibor Vass
parent 397cc42a3c
commit 9b96f27cba
1 changed files with 9 additions and 0 deletions
Download Patch File Download Diff File Expand all files Collapse all files

9
components/cli/docs/reference/builder.md
View File

@ -541,6 +541,9 @@ RUN /bin/bash -c 'source $HOME/.bashrc ; echo $HOME'
> `RUN [ "echo", "$HOME" ]` will not do variable substitution on `$HOME`.
> If you want shell processing then either use the *shell* form or execute
> a shell directly, for example: `RUN [ "sh", "-c", "echo $HOME" ]`.
> When using the exec form and executing a shell directly, as in the case for
> the shell form, it is the shell that is doing the environment variable
> expansion, not docker.
>
> **Note**:
> In the *JSON* form, it is necessary to escape backslashes. This is
@ -607,6 +610,9 @@ instruction as well.
> `CMD [ "echo", "$HOME" ]` will not do variable substitution on `$HOME`.
> If you want shell processing then either use the *shell* form or execute
> a shell directly, for example: `CMD [ "sh", "-c", "echo $HOME" ]`.
> When using the exec form and executing a shell directly, as in the case for
> the shell form, it is the shell that is doing the environment variable
> expansion, not docker.
When used in the shell or exec formats, the `CMD` instruction sets the command
to be executed when running the image.
@ -1075,6 +1081,9 @@ sys 0m 0.03s
> `ENTRYPOINT [ "echo", "$HOME" ]` will not do variable substitution on `$HOME`.
> If you want shell processing then either use the *shell* form or execute
> a shell directly, for example: `ENTRYPOINT [ "sh", "-c", "echo $HOME" ]`.
> When using the exec form and executing a shell directly, as in the case for
> the shell form, it is the shell that is doing the environment variable
> expansion, not docker.
### Shell form ENTRYPOINT example