cargo-fetch(1)
NAME
cargo-fetch — Fetch dependencies of a package from the network
SYNOPSIS
cargo fetch
[options]
DESCRIPTION
If a Cargo.lock
file is available, this command will ensure that all of the
git dependencies and/or registry dependencies are downloaded and locally
available. Subsequent Cargo commands will be able to run offline after a cargo fetch
unless the lock file changes.
If the lock file is not available, then this command will generate the lock file before fetching the dependencies.
If --target
is not specified, then all target dependencies are fetched.
See also the cargo-prefetch
plugin which adds a command to download popular crates. This may be useful if
you plan to use Cargo without a network with the --offline
flag.
OPTIONS
Fetch options
--target
triple- Fetch for the given architecture. The default is all architectures. The general format of the triple is
<arch><sub>-<vendor>-<sys>-<abi>
. Runrustc --print target-list
for a list of supported targets. This flag may be specified multiple times.This may also be specified with the
build.target
config value.Note that specifying this flag makes Cargo run in a different mode where the target artifacts are placed in a separate directory. See the build cache documentation for more details.
Display Options
-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. -q
--quiet
- Do not print cargo log messages.
May also be specified with the
term.quiet
config value. --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.
Manifest Options
--manifest-path
path- Path to the
Cargo.toml
file. By default, Cargo searches for theCargo.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.
May also be specified with the
net.offline
config value. --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 withCargo.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 and requires the
-Z unstable-options
flag to enable (see #14421).
Common Options
+
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 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 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 examplecargo -C path/to/my-project build
.This option is only available on the nightly channel and requires the
-Z unstable-options
flag to enable (see #10098). -h
--help
- Prints help information.
-Z
flag- Unstable (nightly-only) flags to Cargo. Run
cargo -Z help
for details.
ENVIRONMENT
See the reference for details on environment variables that Cargo reads.
EXIT STATUS
0
: Cargo succeeded.101
: Cargo failed to complete.
EXAMPLES
-
Fetch all dependencies:
cargo fetch