table of contents
snap(8) | System Manager's Manual | snap(8) |
NAME¶
snap - Tool to interact with snapsSYNOPSIS¶
snap [OPTIONS]DESCRIPTION¶
The snap command lets you install, configure, refresh and remove snaps. Snaps are packages that work across many different Linux distributions, enabling secure delivery and operation of the latest apps and utilities.OPTIONS¶
Application Options¶
COMMANDS¶
abort¶
Abort a pending changeThe abort command attempts to abort a change that still has pending tasks.
Usage: snap [OPTIONS] abort [abort-OPTIONS]
- --last
- Select last change of given type (install, refresh, remove, try, auto-refresh, etc.). A question mark at the end of the type means to do nothing (instead of returning an error) if no change of the given type is found. Note the question mark could need protecting from the shell.
ack¶
Add an assertion to the systemThe ack command tries to add an assertion to the system assertion database.
The assertion may also be a newer revision of a pre-existing assertion that it will replace.
To succeed the assertion must be valid, its signature verified with a known public key and the assertion consistent with and its prerequisite in the database.
alias¶
Set up a manual aliasThe alias command aliases the given snap application to the given alias.
Once this manual alias is setup the respective application command can be invoked just using the alias.
Usage: snap [OPTIONS] alias [alias-OPTIONS]
- --no-wait
- Do not wait for the operation to finish but just print the change id.
aliases¶
List aliases in the systemThe aliases command lists all aliases available in the system and their status.
$ snap aliases <snap>
Lists only the aliases defined by the specified snap.
An alias noted as undefined means it was explicitly enabled or disabled but is not defined in the current revision of the snap, possibly temporarily (e.g. because of a revert). This can cleared with 'snap alias --reset'.
changes¶
List system changesThe changes command displays a summary of system changes performed recently.
Usage: snap [OPTIONS] changes [changes-OPTIONS]
- --abs-time
- Display absolute times (in RFC 3339 format). Otherwise, display relative times up to 60 days, then YYYY-MM-DD.
check-snapshot¶
Check a snapshotThe check-snapshot command verifies the user, system and configuration data of the snaps included in the specified snapshot.
The check operation runs the same data integrity verification that is performed when a snapshot is restored.
By default, this command checks all the data in a snapshot. Alternatively, you can specify the data of which snaps to check, or for which users, or a combination of these.
If a snap is included in a check-snapshot operation, excluding its system and configuration data from the check is not currently possible. This restriction may be lifted in the future.
Usage: snap [OPTIONS] check-snapshot [check-snapshot-OPTIONS]
- --no-wait
- Do not wait for the operation to finish but just print the change id.
- --users
- Check data of only specific users (comma-separated) (default: all users)
connect¶
Connect a plug to a slotThe connect command connects a plug to a slot. It may be called in the following ways:
$ snap connect <snap>:<plug> <snap>:<slot>
Connects the provided plug to the given slot.
$ snap connect <snap>:<plug> <snap>
Connects the specific plug to the only slot in the provided snap that matches the connected interface. If more than one potential slot exists, the command fails.
$ snap connect <snap>:<plug>
Connects the provided plug to the slot in the core snap with a name matching the plug name.
Usage: snap [OPTIONS] connect [connect-OPTIONS]
- --no-wait
- Do not wait for the operation to finish but just print the change id.
disable¶
Disable a snap in the systemThe disable command disables a snap. The binaries and services of the snap will no longer be available, but all the data is still available and the snap can easily be enabled again.
Usage: snap [OPTIONS] disable [disable-OPTIONS]
- --no-wait
- Do not wait for the operation to finish but just print the change id.
disconnect¶
Disconnect a plug from a slotThe disconnect command disconnects a plug from a slot. It may be called in the following ways:
$ snap disconnect <snap>:<plug> <snap>:<slot>
Disconnects the specific plug from the specific slot.
$ snap disconnect <snap>:<slot or plug>
Disconnects everything from the provided plug or slot. The snap name may be omitted for the core snap.
Usage: snap [OPTIONS] disconnect [disconnect-OPTIONS]
- --no-wait
- Do not wait for the operation to finish but just print the change id.
download¶
Download the given snapThe download command downloads the given snap and its supporting assertions to the current directory with .snap and .assert file extensions, respectively.
Usage: snap [OPTIONS] download [download-OPTIONS]
- --channel
- Use this channel instead of stable
- --edge
- Install from the edge channel
- --beta
- Install from the beta channel
- --candidate
- Install from the candidate channel
- --stable
- Install from the stable channel
- --revision
- Download the given revision of a snap, to which you must have developer access
enable¶
Enable a snap in the systemThe enable command enables a snap that was previously disabled.
Usage: snap [OPTIONS] enable [enable-OPTIONS]
- --no-wait
- Do not wait for the operation to finish but just print the change id.
find¶
Find packages to installThe find command queries the store for available packages in the stable channel.
With the --private flag, which requires the user to be logged-in to the store (see 'snap help login'), it instead searches for private snaps that the user has developer access to, either directly or through the store's collaboration feature.
A green check mark (given color and unicode support) after a publisher name indicates that the publisher has been verified.
Usage: snap [OPTIONS] find [find-OPTIONS]
- Aliases: search
- --private
- Search private snaps
- --narrow
- Only search for snaps in “stable”
- --section [="show-all-sections-please"] <default: "no-section-specified">
- Restrict the search to a given section
- --color <default: "auto">
- Use a little bit of color to highlight some things.
- --unicode <default: "auto">
- Use a little bit of Unicode to improve legibility.
forget¶
Delete a snapshotThe forget command deletes a snapshot. This operation can not be undone.
A snapshot contains archives for the user, system and configuration data of each snap included in the snapshot.
By default, this command forgets all the data in a snapshot. Alternatively, you can specify the data of which snaps to forget.
Usage: snap [OPTIONS] forget [forget-OPTIONS]
- --no-wait
- Do not wait for the operation to finish but just print the change id.
get¶
Print configuration optionsThe get command prints configuration options for the provided snap.
$ snap get snap-name username frank
If multiple option names are provided, a document is returned:
$ snap get snap-name username password { "username": "frank", "password": "..." }
Nested values may be retrieved via a dotted path:
$ snap get snap-name author.name frank
Usage: snap [OPTIONS] get [get-OPTIONS]
- -t
- Strict typing with nulls and quoted strings
- -d
- Always return document, even with single key
- -l
- Always return list, even with single key
help¶
Show help about a commandThe help command displays information about snap commands.
Usage: snap [OPTIONS] help [help-OPTIONS]
- --all
- Show a short summary of all commands
info¶
Show detailed information about snapsThe info command shows detailed information about snaps.
The snaps can be specified by name or by path; names are looked for both in the store and in the installed snaps; paths can refer to a .snap file, or to a directory that contains an unpacked snap suitable for 'snap try' (an example of this would be the 'prime' directory snapcraft produces).
Usage: snap [OPTIONS] info [info-OPTIONS]
- --color <default: "auto">
- Use a little bit of color to highlight some things.
- --unicode <default: "auto">
- Use a little bit of Unicode to improve legibility.
- --abs-time
- Display absolute times (in RFC 3339 format). Otherwise, display relative times up to 60 days, then YYYY-MM-DD.
- --verbose
- Include more details on the snap (expanded notes, base, etc.)
install¶
Install snaps on the systemThe install command installs the named snaps on the system.
To install multiple instances of the same snap, append an underscore and a unique identifier (for each instance) to a snap's name.
With no further options, the snaps are installed tracking the stable channel, with strict security confinement.
Revision choice via the --revision override requires the the user to have developer access to the snap, either directly or through the store's collaboration feature, and to be logged in (see 'snap help login').
Note a later refresh will typically undo a revision override, taking the snap back to the current revision of the channel it's tracking.
Use --name to set the instance name when installing from snap file.
Usage: snap [OPTIONS] install [install-OPTIONS]
- --color <default: "auto">
- Use a little bit of color to highlight some things.
- --unicode <default: "auto">
- Use a little bit of Unicode to improve legibility.
- --no-wait
- Do not wait for the operation to finish but just print the change id.
- --channel
- Use this channel instead of stable
- --edge
- Install from the edge channel
- --beta
- Install from the beta channel
- --candidate
- Install from the candidate channel
- --stable
- Install from the stable channel
- --devmode
- Put snap in development mode and disable security confinement
- --jailmode
- Put snap in enforced confinement mode
- --classic
- Put snap in classic mode and disable security confinement
- --revision
- Install the given revision of a snap, to which you must have developer access
- --dangerous
- Install the given snap file even if there are no pre-acknowledged signatures for it, meaning it was not verified and could be dangerous (--devmode implies this)
- --unaliased
- Install the given snap without enabling its automatic aliases
- --name
- Install the snap file under the given instance name
interface¶
Show details of snap interfacesThe interface command shows details of snap interfaces.
If no interface name is provided, a list of interface names with at least one connection is shown, or a list of all interfaces if --all is provided.
Usage: snap [OPTIONS] interface [interface-OPTIONS]
- --attrs
- Show interface attributes
- --all
- Include unused interfaces
interfaces¶
List interfaces' slots and plugsThe interfaces command lists interfaces available in the system.
By default all slots and plugs, used and offered by all snaps, are displayed.
$ snap interfaces <snap>:<slot or plug>
Lists only the specified slot or plug.
$ snap interfaces <snap>
Lists the slots offered and plugs used by the specified snap.
$ snap interfaces -i=<interface> [<snap>]
Filters the complete output so only plugs and/or slots matching the provided details are listed.
Usage: snap [OPTIONS] interfaces [interfaces-OPTIONS]
- -i
- Constrain listing to specific interfaces
known¶
Show known assertions of the provided typeThe known command shows known assertions of the provided type. If header=value pairs are provided after the assertion type, the assertions shown must also have the specified headers matching the provided values.
Usage: snap [OPTIONS] known [known-OPTIONS]
- --remote
list¶
List installed snapsThe list command displays a summary of snaps installed in the current system.
A green check mark (given color and unicode support) after a publisher name indicates that the publisher has been verified.
Usage: snap [OPTIONS] list [list-OPTIONS]
- --all
- Show all revisions
- --color <default: "auto">
- Use a little bit of color to highlight some things.
- --unicode <default: "auto">
- Use a little bit of Unicode to improve legibility.
login¶
Authenticate to snapd and the storeThe login command authenticates the user to snapd and the snap store, and saves credentials into the ~/.snap/auth.json file. Further communication with snapd will then be made using those credentials.
It's not necessary to log in to interact with snapd. Doing so, however, enables purchasing of snaps using 'snap buy', as well as some some developer-oriented features as detailed in the help for the find, install and refresh commands.
An account can be set up at https://login.ubuntu.com
logout¶
Log out of snapd and the storeThe logout command logs the current user out of snapd and the store.
logs¶
Retrieve logs for servicesThe logs command fetches logs of the given services and displays them in chronological order.
Usage: snap [OPTIONS] logs [logs-OPTIONS]
- -n <default: "10">
- Show only the given number of lines, or 'all'.
- -f
- Wait for new lines and print them as they come in.
okay¶
Acknowledge warningsThe okay command acknowledges the warnings listed with 'snap warnings'.
Once acknowledged a warning won't appear again unless it re-occurrs and sufficient time has passed.
pack¶
Pack the given directory as a snapThe pack command packs the given snap-dir as a snap and writes the result to target-dir. If target-dir is omitted, the result is written to current directory. If both source-dir and target-dir are omitted, the pack command packs the current directory.
The default file name for a snap can be derived entirely from its snap.yaml, but in some situations it's simpler for a script to feed the filename in. In those cases, --filename can be given to override the default. If this filename is not absolute it will be taken as relative to target-dir.
When used with --check-skeleton, pack only checks whether snap-dir contains valid snap metadata and raises an error otherwise. Application commands listed in snap metadata file, but appearing with incorrect permission bits result in an error. Commands that are missing from snap-dir are listed in diagnostic messages.
Usage: snap [OPTIONS] pack [pack-OPTIONS]
- --check-skeleton
- Validate snap-dir metadata only
- --filename
- Output to this filename
prefer¶
Enable aliases from a snap, disabling any conflicting aliasesThe prefer command enables all aliases of the given snap in preference to conflicting aliases of other snaps whose aliases will be disabled (or removed, for manual ones).
Usage: snap [OPTIONS] prefer [prefer-OPTIONS]
- --no-wait
- Do not wait for the operation to finish but just print the change id.
refresh¶
Refresh snaps in the systemThe refresh command updates the specified snaps, or all snaps in the system if none are specified.
With no further options, the snaps are refreshed to the current revision of the channel they're tracking, preserving their confinement options.
Revision choice via the --revision override requires the the user to have developer access to the snap, either directly or through the store's collaboration feature, and to be logged in (see 'snap help login').
Note a later refresh will typically undo a revision override.
Usage: snap [OPTIONS] refresh [refresh-OPTIONS]
- --color <default: "auto">
- Use a little bit of color to highlight some things.
- --unicode <default: "auto">
- Use a little bit of Unicode to improve legibility.
- --abs-time
- Display absolute times (in RFC 3339 format). Otherwise, display relative times up to 60 days, then YYYY-MM-DD.
- --no-wait
- Do not wait for the operation to finish but just print the change id.
- --channel
- Use this channel instead of stable
- --edge
- Install from the edge channel
- --beta
- Install from the beta channel
- --candidate
- Install from the candidate channel
- --stable
- Install from the stable channel
- --devmode
- Put snap in development mode and disable security confinement
- --jailmode
- Put snap in enforced confinement mode
- --classic
- Put snap in classic mode and disable security confinement
- --amend
- Allow refresh attempt on snap unknown to the store
- --revision
- Refresh to the given revision, to which you must have developer access
- --list
- Show the new versions of snaps that would be updated with the next refresh
- --time
- Show auto refresh information but do not perform a refresh
- --ignore-validation
- Ignore validation by other snaps blocking the refresh
remove¶
Remove snaps from the systemThe remove command removes the named snap instance from the system.
By default all the snap revisions are removed, including their data and the common data directory. When a --revision option is passed only the specified revision is removed.
Usage: snap [OPTIONS] remove [remove-OPTIONS]
- --no-wait
- Do not wait for the operation to finish but just print the change id.
- --revision
- Remove only the given revision
restart¶
Restart servicesThe restart command restarts the given services.
If the --reload option is given, for each service whose app has a reload command, a reload is performed instead of a restart.
Usage: snap [OPTIONS] restart [restart-OPTIONS]
- --no-wait
- Do not wait for the operation to finish but just print the change id.
- --reload
- If the service has a reload command, use it instead of restarting.
restore¶
Restore a snapshotThe restore command replaces the current user, system and configuration data of included snaps, with the corresponding data from the specified snapshot.
By default, this command restores all the data in a snapshot. Alternatively, you can specify the data of which snaps to restore, or for which users, or a combination of these.
If a snap is included in a restore operation, excluding its system and configuration data from the restore is not currently possible. This restriction may be lifted in the future.
Usage: snap [OPTIONS] restore [restore-OPTIONS]
- --no-wait
- Do not wait for the operation to finish but just print the change id.
- --users
- Restore data of only specific users (comma-separated) (default: all users)
revert¶
Reverts the given snap to the previous stateThe revert command reverts the given snap to its state before the latest refresh. This will reactivate the previous snap revision, and will use the original data that was associated with that revision, discarding any data changes that were done by the latest revision. As an exception, data which the snap explicitly chooses to share across revisions is not touched by the revert process.
Usage: snap [OPTIONS] revert [revert-OPTIONS]
- --no-wait
- Do not wait for the operation to finish but just print the change id.
- --devmode
- Put snap in development mode and disable security confinement
- --jailmode
- Put snap in enforced confinement mode
- --classic
- Put snap in classic mode and disable security confinement
- --revision
- Revert to the given revision
run¶
Run the given snap commandThe run command executes the given snap command with the right confinement and environment.
Usage: snap [OPTIONS] run [run-OPTIONS]
- --shell
- Run a shell instead of the command (useful for debugging)
- --strace [="with-strace"] <default: "no-strace">
- Run the command under strace (useful for debugging). Extra strace options can be specified as well here. Pass --raw to strace early snap helpers.
- --gdb
- Run the command with gdb
- --trace-exec
- Display exec calls timing data
save¶
Save a snapshot of the current dataThe save command creates a snapshot of the current user, system and configuration data for the given snaps.
By default, this command saves the data of all snaps for all users. Alternatively, you can specify the data of which snaps to save, or for which users, or a combination of these.
If a snap is included in a save operation, excluding its system and configuration data from the snapshot is not currently possible. This restriction may be lifted in the future.
Usage: snap [OPTIONS] save [save-OPTIONS]
- --no-wait
- Do not wait for the operation to finish but just print the change id.
- --abs-time
- Display absolute times (in RFC 3339 format). Otherwise, display short relative times.
- --users
- Snapshot data of only specific users (comma-separated) (default: all users)
saved¶
List currently stored snapshotsThe saved command displays a list of snapshots that have been created previously with the 'save' command.
Usage: snap [OPTIONS] saved [saved-OPTIONS]
- --abs-time
- Display absolute times (in RFC 3339 format). Otherwise, display short relative times.
- --id
- Show only a specific snapshot.
services¶
Query the status of servicesThe services command lists information about the services specified, or about the services in all currently installed snaps.
set¶
Change configuration optionsThe set command changes the provided configuration options as requested.
$ snap set snap-name username=frank password=$PASSWORD
All configuration changes are persisted at once, and only after the snap's configuration hook returns successfully.
Nested values may be modified via a dotted path:
$ snap set author.name=frank
Usage: snap [OPTIONS] set [set-OPTIONS]
- --no-wait
- Do not wait for the operation to finish but just print the change id.
start¶
Start servicesThe start command starts, and optionally enables, the given services.
Usage: snap [OPTIONS] start [start-OPTIONS]
- --no-wait
- Do not wait for the operation to finish but just print the change id.
- --enable
- As well as starting the service now, arrange for it to be started on boot.
stop¶
Stop servicesThe stop command stops, and optionally disables, the given services.
Usage: snap [OPTIONS] stop [stop-OPTIONS]
- --no-wait
- Do not wait for the operation to finish but just print the change id.
- --disable
- As well as stopping the service now, arrange for it to no longer be started on boot.
switch¶
Switches snap to a different channelThe switch command switches the given snap to a different channel without doing a refresh.
Usage: snap [OPTIONS] switch [switch-OPTIONS]
- --no-wait
- Do not wait for the operation to finish but just print the change id.
- --channel
- Use this channel instead of stable
- --edge
- Install from the edge channel
- --beta
- Install from the beta channel
- --candidate
- Install from the candidate channel
- --stable
- Install from the stable channel
tasks¶
List a change's tasksThe tasks command displays a summary of tasks associated with an individual change.
Usage: snap [OPTIONS] tasks [tasks-OPTIONS]
- Aliases: change
- --abs-time
- Display absolute times (in RFC 3339 format). Otherwise, display relative times up to 60 days, then YYYY-MM-DD.
- --last
- Select last change of given type (install, refresh, remove, try, auto-refresh, etc.). A question mark at the end of the type means to do nothing (instead of returning an error) if no change of the given type is found. Note the question mark could need protecting from the shell.
try¶
Test an unpacked snap in the systemThe try command installs an unpacked snap into the system for testing purposes. The unpacked snap content continues to be used even after installation, so non-metadata changes there go live instantly. Metadata changes such as those performed in snap.yaml will require reinstallation to go live.
If snap-dir argument is omitted, the try command will attempt to infer it if either snapcraft.yaml file and prime directory or meta/snap.yaml file can be found relative to current working directory.
Usage: snap [OPTIONS] try [try-OPTIONS]
- --no-wait
- Do not wait for the operation to finish but just print the change id.
- --devmode
- Put snap in development mode and disable security confinement
- --jailmode
- Put snap in enforced confinement mode
- --classic
- Put snap in classic mode and disable security confinement
unalias¶
Remove a manual alias, or the aliases for an entire snapThe unalias command removes a single alias if the provided argument is a manual alias, or disables all aliases of a snap, including manual ones, if the argument is a snap name.
Usage: snap [OPTIONS] unalias [unalias-OPTIONS]
- --no-wait
- Do not wait for the operation to finish but just print the change id.
version¶
Show version detailsThe version command displays the versions of the running client, server, and operating system.
wait¶
Wait for configurationThe wait command waits until a configration becomes true.
warnings¶
List warningsThe warnings command lists the warnings that have been reported to the system.
Once warnings have been listed with 'snap warnings', 'snap okay' may be used to silence them. A warning that's been silenced in this way will not be listed again unless it happens again, _and_ a cooldown time has passed.
Warnings expire automatically, and once expired they are forgotten.
Usage: snap [OPTIONS] warnings [warnings-OPTIONS]
- --abs-time
- Display absolute times (in RFC 3339 format). Otherwise, display relative times up to 60 days, then YYYY-MM-DD.
- --all
- Show all warnings
- --verbose
- Show more information
watch¶
Watch a change in progressThe watch command waits for the given change-id to finish and shows progress (if available).
Usage: snap [OPTIONS] watch [watch-OPTIONS]
- --last
- Select last change of given type (install, refresh, remove, try, auto-refresh, etc.). A question mark at the end of the type means to do nothing (instead of returning an error) if no change of the given type is found. Note the question mark could need protecting from the shell.
whoami¶
Show the email the user is logged in withThe whoami command shows the email the user is logged in with.
6 June 2019 |