CARGO-PKGID(1) General Commands Manual CARGO-PKGID(1)

cargo-pkgid — Print a fully qualified package specification

cargo pkgid [options] [spec]

Given a spec argument, print out the fully qualified package ID specifier for a package or dependency in the current workspace. This command will generate an error if spec is ambiguous as to which package it refers to in the dependency graph. If no spec is given, then the specifier for the local package is printed.

This command requires that a lockfile is available and dependencies have been fetched.

A package specifier consists of a name, version, and source URL. You are allowed to use partial specifiers to succinctly match a specific package as long as it matches only one package. This specifier is also used by other parts in Cargo, such as cargo-metadata(1) and JSON messages https://doc.rust-lang.org/cargo/reference/external-tools.html#json-messages emitted by Cargo.

The format of a spec can be one of the following:

SPEC Structure Example SPEC
name bitflags
name@version bitflags@1.0.4
url https://github.com/rust-lang/cargo
url#version https://github.com/rust-lang/cargo#0.33.0
url#name https://github.com/rust-lang/crates.io-index#bitflags
url#name@version https://github.com/rust-lang/cargo#crates-io@0.21.0

The specification grammar can be found in chapter Package ID Specifications https://doc.rust-lang.org/cargo/reference/pkgid-spec.html.

-p spec, --package spec

Get the package ID for the given package instead of the current package.

-v, --verbose

Use verbose output. May be specified twice for “very verbose” output which includes extra output such as dependency warnings and build script output. May also be specified with the term.verbose config value https://doc.rust-lang.org/cargo/reference/config.html.

-q, --quiet

Do not print cargo log messages. May also be specified with the term.quiet config value https://doc.rust-lang.org/cargo/reference/config.html.

--color when

Control when colored output is used. Valid values:
•auto (default): Automatically detect if color support is available on the terminal.
•always: Always display colors.
•never: Never display colors.

May also be specified with the term.color config value https://doc.rust-lang.org/cargo/reference/config.html.

--manifest-path path

Path to the Cargo.toml file. By default, Cargo searches for the Cargo.toml file in the current directory or any parent directory.

--locked

Asserts that the exact same dependencies and versions are used as when the existing Cargo.lock file was originally generated. Cargo will exit with an error when either of the following scenarios arises:
•The lock file is missing.
•Cargo attempted to change the lock file due to a different dependency resolution.

It may be used in environments where deterministic builds are desired, such as in CI pipelines.

--offline

Prevents Cargo from accessing the network for any reason. Without this flag, Cargo will stop with an error if it needs to access the network and the network is not available. With this flag, Cargo will attempt to proceed without the network if possible.

Beware that this may result in different dependency resolution than online mode. Cargo will restrict itself to crates that are downloaded locally, even if there might be a newer version as indicated in the local copy of the index. See the cargo-fetch(1) command to download dependencies before going offline.

May also be specified with the net.offline config value https://doc.rust-lang.org/cargo/reference/config.html.

--frozen

Equivalent to specifying both --locked and --offline.

--lockfile-path PATH

Changes the path of the lockfile from the default (<workspace_root>/Cargo.lock) to PATH. PATH must end with Cargo.lock (e.g. --lockfile-path /tmp/temporary-lockfile/Cargo.lock). Note that providing --lockfile-path will ignore existing lockfile at the default path, and instead will either use the lockfile from PATH, or write a new lockfile into the provided PATH if it doesn’t exist. This flag can be used to run most commands in read-only directories, writing lockfile into the provided PATH.

This option is only available on the nightly channel https://doc.rust-lang.org/book/appendix-07-nightly-rust.html and requires the -Z unstable-options flag to enable (see #14421 https://github.com/rust-lang/cargo/issues/14421).

+toolchain

If Cargo has been installed with rustup, and the first argument to cargo begins with +, it will be interpreted as a rustup toolchain name (such as +stable or +nightly). See the rustup documentation https://rust-lang.github.io/rustup/overrides.html for more information about how toolchain overrides work.

--config KEY=VALUE or PATH

Overrides a Cargo configuration value. The argument should be in TOML syntax of KEY=VALUE, or provided as a path to an extra configuration file. This flag may be specified multiple times. See the command-line overrides section https://doc.rust-lang.org/cargo/reference/config.html#command-line-overrides for more information.

-C PATH

Changes the current working directory before executing any specified operations. This affects things like where cargo looks by default for the project manifest (Cargo.toml), as well as the directories searched for discovering .cargo/config.toml, for example. This option must appear before the command name, for example cargo -C path/to/my-project build.

This option is only available on the nightly channel https://doc.rust-lang.org/book/appendix-07-nightly-rust.html and requires the -Z unstable-options flag to enable (see #10098 https://github.com/rust-lang/cargo/issues/10098).

-h, --help

Prints help information.

-Z flag

Unstable (nightly-only) flags to Cargo. Run cargo -Z help for details.

See the reference https://doc.rust-lang.org/cargo/reference/environment-variables.html for details on environment variables that Cargo reads.

•0: Cargo succeeded.
•101: Cargo failed to complete.

1.Retrieve package specification for foo package: 
cargo pkgid foo
2.Retrieve package specification for version 1.0.0 of foo: 
cargo pkgid foo@1.0.0
3.Retrieve package specification for foo from crates.io: 
cargo pkgid https://github.com/rust-lang/crates.io-index#foo
4.Retrieve package specification for foo from a local package: 
cargo pkgid file:///path/to/local/package#foo

cargo(1), cargo-generate-lockfile(1), cargo-metadata(1), Package ID Specifications https://doc.rust-lang.org/cargo/reference/pkgid-spec.html, JSON messages https://doc.rust-lang.org/cargo/reference/external-tools.html#json-messages