Results for “command substitution”
Small, practical examples. Search by task or narrow things down below.
Create a runtime file during the build
Docker / Compose: RUN executes during the build while CMD executes when a container starts.
Docker / Compose✓ Tested
Create a small file at build time
Docker / Compose: Create a small file at build time with a complete introductory Dockerfile.
Docker / Compose✓ Tested
Create a symbolic link
Create a relative symbolic link to a file and inspect its target with readlink.
symlink✓ Tested
Create an annotated release tag
Mark a revision with a readable release description.
tag✓ Tested
Declare a named volume in Compose
Mount persistent storage at a service path.
Compose✓ Tested
Define a first Compose service
Docker / Compose: Define a first Compose service in a small Compose file.
Docker / Compose✓ Tested
Detect an error inside a pipeline
Use pipefail to observe failure before the last pipeline command.
pipefail✓ Tested
Disable a service’s network interfaces
Docker / Compose: network_mode none leaves only the loopback interface.
Docker / Compose✓ Tested
Drop all optional Linux capabilities
Docker / Compose: The effective capability mask becomes zero after cap-drop ALL.
Docker / Compose✓ Tested
Drop capabilities for a Compose service
Docker / Compose: cap_drop ALL removes optional Linux capabilities.
Docker / Compose✓ Tested
Enable an init process for a service
Docker / Compose: init adds a small PID 1 process to forward signals and reap children.
Docker / Compose✓ Tested
Exclude files from the build context
Docker / Compose: A dockerignore file prevents selected local files from being copied.
Docker / Compose✓ Tested