diff --git a/docs/containers-transports.5.md b/docs/containers-transports.5.md index 481bdb73c7..edf9410f33 100644 --- a/docs/containers-transports.5.md +++ b/docs/containers-transports.5.md @@ -9,7 +9,7 @@ containers-transports - description of supported transports for copying and stor ## DESCRIPTION Tools which use the containers/image library, including skopeo(1), buildah(1), podman(1), all share a common syntax for referring to container images in various locations. -The general form of the syntax is _transport:details_, where details are dependent on the specified transport, which are documented below. +The general form of the syntax is _transport_`:`_details_, where details are dependent on the specified transport, which are documented below. The semantics of the image names ultimately depend on the environment where they are evaluated. For example: if evaluated on a remote server, image names @@ -18,14 +18,14 @@ directory of the image consumer. -### **containers-storage**:[**[**storage-specifier**]**]{image-id|docker-reference[@image-id]} +### **containers-storage:**[**[**_storage-specifier_**]**]{_image-id_|_docker-reference_[**@**_image-id_]} An image located in a local containers storage. The format of _docker-reference_ is described in detail in the **docker** transport. -The _storage-specifier_ allows for referencing storage locations on the file system and has the format `[[driver@]root[+run-root][:options]]` where the optional `driver` refers to the storage driver (e.g., overlay or btrfs) and where `root` is an absolute path to the storage's root directory. -The optional `run-root` can be used to specify the run directory of the storage where all temporary writable content is stored. -The optional `options` are a comma-separated list of driver-specific options. +The _storage-specifier_ allows for referencing storage locations on the file system and has the format `[`[_driver_`@`]_root_[`+`_run-root_][`:`_options_]`]` where the optional _driver_ refers to the storage driver (e.g., `overlay` or `btrfs`) and where _root_ is an absolute path to the storage's root directory. +The optional _run-root_ can be used to specify the run directory of the storage where all temporary writable content is stored. +The optional _options_ are a comma-separated list of driver-specific options. Please refer to containers-storage.conf(5) for further information on the drivers and supported options. ### **dir:**_path_ @@ -40,34 +40,34 @@ By default, uses the authorization state in `$XDG_RUNTIME_DIR/containers/auth.js If the authorization state is not found there, `$HOME/.docker/config.json` is checked, which is set using docker-login(1). The containers-registries.conf(5) further allows for configuring various settings of a registry. -Note that a _docker-reference_ has the following format: _name_[**:**_tag_ | **@**_digest_]. +Note that a _docker-reference_ has the following format: _name_[`:`_tag_ | `@`_digest_]. While the docker transport does not support both a tag and a digest at the same time some formats like containers-storage do. Digests can also be used in an image destination as long as the manifest matches the provided digest. -The docker transport supports pushing images without a tag or digest to a registry when the image name is suffixed with **@@unknown-digest@@**. The _name_**@@unknown-digest@@** reference format cannot be used with a reference that has a tag or digest. +The docker transport supports pushing images without a tag or digest to a registry when the image name is suffixed with `@@unknown-digest@@`. The _name_`@@unknown-digest@@` reference format cannot be used with a reference that has a tag or digest. The digest of images can be explored with skopeo-inspect(1). -If `name` does not contain a slash, it is treated as `docker.io/library/name`. -Otherwise, the component before the first slash is checked if it is recognized as a `hostname[:port]` (i.e., it contains either a . or a :, or the component is exactly localhost). -If the first component of name is not recognized as a `hostname[:port]`, `name` is treated as `docker.io/name`. +If _name_ does not contain a slash, it is treated as `docker.io/library/`_name_. +Otherwise, the component before the first slash is checked if it is recognized as a _hostname_[`:`_port_] (i.e., it contains either a `.` or a `:`, or the component is exactly `localhost`). +If the first component of name is not recognized as a _hostname_[`:`_port_], _name_ is treated as `docker.io/`_name_. -### **docker-archive:**_path[:{docker-reference|@source-index}]_ +### **docker-archive:**_path_[`:`{_docker-reference_|`@`_source-index_}] An image is stored in the docker-save(1) formatted file. _docker-reference_ must not contain a digest. -Alternatively, for reading archives, @_source-index_ is a zero-based index in archive manifest +Alternatively, for reading archives, `@`_source-index_ is a zero-based index in archive manifest (to access untagged images). -If neither _docker-reference_ nor @_source_index is specified when reading an archive, the archive must contain exactly one image. +If neither _docker-reference_ nor `@`_source_index is specified when reading an archive, the archive must contain exactly one image. The _path_ can refer to a stream, e.g. `docker-archive:/dev/stdin`. -### **docker-daemon:**_docker-reference|algo:digest_ +### **docker-daemon:**_docker-reference_|_algo_`:`_digest_ An image stored in the docker daemon's internal storage. -The image must be specified as a _docker-reference_ or in an alternative _algo:digest_ format when being used as an image source. -The _algo:digest_ refers to the image ID reported by docker-inspect(1). +The image must be specified as a _docker-reference_ or in an alternative _algo_`:`_digest_ format when being used as an image source. +The _algo_`:`_digest_ refers to the image ID reported by docker-inspect(1). -### **oci:**_path[:reference]_ +### **oci:**_path_[`:`_reference_] An image in a directory structure compliant with the "Open Container Image Layout Specification" at _path_. @@ -75,7 +75,7 @@ The _path_ value terminates at the first `:` character; any further `:` characte The _reference_ is used to set, or match, the `org.opencontainers.image.ref.name` annotation in the top-level index. If _reference_ is not specified when reading an image, the directory must contain exactly one image. -### **oci-archive:**_path[:reference]_ +### **oci-archive:**_path_[`:`_reference_] An image in a tar(1) archive with contents compliant with the "Open Container Image Layout Specification" at _path_. @@ -83,10 +83,10 @@ The _path_ value terminates at the first `:` character; any further `:` characte The _reference_ is used to set, or match, the `org.opencontainers.image.ref.name` annotation in the top-level index. If _reference_ is not specified when reading an archive, the archive must contain exactly one image. -### **ostree:**_docker-reference[@/absolute/repo/path]_ +### **ostree:**_docker-reference_[`@`_/absolute/repo/path_] An image in the local ostree(1) repository. -_/absolute/repo/path_ defaults to _/ostree/repo_. +_/absolute/repo/path_ defaults to `/ostree/repo`. ### **sif:**_path_