new docker-build-ext2 script

[mikbras]

Simple internal script to build a docker image and then uses mount-docker-image, writing the resulting root file system to an EXT2 file. For example:

# docker-build-ext2 Dockerfile ext2rootfs

[mikbras]

Update PR to address two comments by Paul:

• add trap cleanup EXIT handler
• forward an extraneous arguments to docker (using $*)

The second change gives the command the following syntax

$ docker-build-ext2 ext2_image <docker_build_arguments...>

Where the <docker_build_arguments> are just passed on to the docker build command.

The minimal command looks like this:

$ docker-build-ext2 ext2_image .

Where . is the path of the docker build directory (passed on to docker).

[radhikaj]

Tagging with [REVISIT] and closing for now since this is not being currently worked on. Use the reopen button to reopen any time. Your changes are saved.