asciinema

NAME

asciinema - terminal session recorder

SYNOPSIS

asciinema --version

asciinema command [options] [ args]

asciinema lets you easily record terminal sessions, replay them in a terminal as well as in a web browser and share them on the web. asciinema is Free and Open Source Software licensed under the GNU General Public License v3.

COMMANDS

asciinema is composed of multiple commands, similar to git, apt-get or brew.

When you run asciinema with no arguments a help message is displayed, listing all available commands with their options.

rec [ filename]

Record terminal session.

By running asciinema rec [filename] you start a new recording session. The command (process) that is recorded can be specified with -c option (see below), and defaults to $SHELL which is what you want in most cases.

You can temporarily pause recording of terminal by pressing Ctrl+\. This is useful when you want to execute some commands during the recording session that should not be captured (e.g. pasting secrets). Resume by pressing Ctrl+\ again.

Recording finishes when you exit the shell (hit Ctrl+D or type exit). If the recorded process is not a shell then recording finishes when the process exits.

If the filename argument is omitted then (after asking for confirmation) the resulting asciicast is uploaded to asciinema-server (https://github.com/asciinema/asciinema-server) (by default to asciinema.org), where it can be watched and shared.

If the filename argument is given then the resulting recording (called asciicast) is saved to a local file. It can later be replayed with asciinema play <filename> and/or uploaded to asciinema server with asciinema upload <filename>.

ASCIINEMA_REC=1 is added to recorded process environment variables. This can be used by your shell’s config file (.bashrc, .zshrc) to alter the prompt or play a sound when the shell is being recorded.

Available options:

--stdin: Enable stdin (keyboard) recording (see below)

--append: Append to existing recording

--raw: Save raw STDOUT output, without timing information or other metadata

--overwrite: Overwrite the recording if it already exists

-c, --command=<command>: Specify command to record, defaults to $SHELL

-e, --env=<var-names>: List of environment variables to capture, defaults to SHELL,TERM

-t, --title=<title>: Specify the title of the asciicast

-i, --idle-time-limit=<sec>: Limit recorded terminal inactivity to max <sec> seconds

--cols=<n>: Override terminal columns for recorded process

--rows=<n>: Override terminal rows for recorded process

-y, --yes: Answer “yes” to all prompts (e.g. upload confirmation)

-q, --quiet: Be quiet, suppress all notices/warnings (implies -y)

Stdin recording allows for capturing of all characters typed in by the user in the currently recorded shell. This may be used by a player (e.g. asciinema-player (https://github.com/asciinema/asciinema-player)) to display pressed keys. Because it’s basically a key-logging (scoped to a single shell instance), it’s disabled by default, and has to be explicitly enabled via –stdin option.

play < filename>

Replay recorded asciicast in a terminal.

This command replays a given asciicast (as recorded by rec command) directly in your terminal. The asciicast can be read from a file or from stdin (`-'):

Playing from a local file:

asciinema play /path/to/asciicast.cast

Playing from HTTP(S) URL:

asciinema play https://asciinema.org/a/22124.cast
asciinema play http://example.com/demo.cast

Playing from asciicast page URL (requires <link rel="alternate" type="application/x-asciicast" href="/my/ascii.cast"> in page’s HTML):

asciinema play https://asciinema.org/a/22124
asciinema play http://example.com/blog/post.html

Playing from stdin:

cat /path/to/asciicast.cast | asciinema play -
ssh user@host cat asciicast.cast | asciinema play -

Playing from IPFS:

asciinema play dweb:/ipfs/QmNe7FsYaHc9SaDEAEXbaagAzNw9cH7YbzN4xV7jV1MCzK/ascii.cast

Available options:

-i, --idle-time-limit=<sec>: Limit replayed terminal inactivity to max <sec> seconds (can be fractional)

-s, --speed=<factor>: Playback speed (can be fractional)

While playing the following keyboard shortcuts are available:

Space: Toggle pause

.: Step through a recording a frame at a time (when paused)

Ctrl+C: Exit

Recommendation: run `asciinema play' in a terminal of dimensions not smaller than the one used for recording as there’s no “transcoding” of control sequences for the new terminal size.

cat < filename>

Print full output of recorded asciicast to a terminal.

While asciinema play replays the recorded session using timing information saved in the asciicast, asciinema cat dumps the full output (including all escape sequences) to a terminal immediately.

asciinema cat existing.cast >output.txt gives the same result as recording via asciinema rec --raw output.txt.

upload < filename>

Upload recorded asciicast to asciinema.org site.

This command uploads given asciicast (recorded by rec command) to asciinema.org, where it can be watched and shared.

asciinema rec demo.cast + asciinema play demo.cast + asciinema upload demo.cast is a nice combo if you want to review an asciicast before publishing it on asciinema.org.

auth

Link and manage your install ID with your asciinema.org user account.

If you want to manage your recordings (change title/theme, delete) at asciinema.org you need to link your “install ID” with your asciinema.org user account.

This command displays the URL to open in a web browser to do that. You may be asked to log in first.

Install ID is a random ID (UUID v4 (https://en.wikipedia.org/wiki/Universally_unique_identifier)) generated locally when you run asciinema for the first time, and saved at $HOME/.config/asciinema/install-id. It’s purpose is to connect local machine with uploaded recordings, so they can later be associated with asciinema.org account. This way we decouple uploading from account creation, allowing them to happen in any order.

Note: A new install ID is generated on each machine and system user account you use asciinema on. So in order to keep all recordings under a single asciinema.org account you need to run asciinema auth on all of those machines. If you’re already logged in on asciinema.org website and you run `asciinema auth' from a new computer then this new device will be linked to your account.

While you CAN synchronize your config file (which keeps the API token) across all your machines so all use the same token, that’s not necessary. You can assign new tokens to your account from as many machines as you want.

Note: asciinema versions prior to 2.0 confusingly referred to install ID as “API token”.

EXAMPLES

Record your first session:

asciinema rec first.cast

End your session:

exit

Now replay it with double speed:

asciinema play -s 2 first.cast

Or with normal speed but with idle time limited to 2 seconds:

asciinema play -i 2 first.cast

You can pass -i 2 to asciinema rec as well, to set it permanently on a recording. Idle time limiting makes the recordings much more interesting to watch, try it.

If you want to watch and share it on the web, upload it:

asciinema upload first.cast

The above uploads it to <https://asciinema.org>, which is a default asciinema-server (<https://github.com/asciinema/asciinema-server>) instance, and prints a secret link you can use to watch your recording in a web browser.

You can record and upload in one step by omitting the filename:

asciinema rec

You’ll be asked to confirm the upload when the recording is done, so nothing is sent anywhere without your consent.

Tricks

Record slowly, play faster:: First record a session where you can take your time to type slowly what you want to show in the recording:

asciinema rec initial.cast

Then record the replay of `initial.cast' as `final.cast', but with five times the initially recorded speed, with all pauses capped to two seconds and with a title set as “My fancy title”::

asciinema rec -c "asciinema play -s 5 -i 2 initial.cast" -t "My fancy title" final.cast

Play from stdin:

cat /path/to/asciicast.json | asciinema play -

Play file from remote host accessible with SSH:

ssh user@host cat /path/to/asciicat.json | asciinema play -

ENVIRONMENT

ASCIINEMA_API_URL: This variable allows overriding asciinema-server URL (which defaults to https://asciinema.org) in case you’re running your own asciinema-server instance.

ASCIINEMA_CONFIG_HOME: This variable allows overriding config directory location. Default location is $XDG_CONFIG_HOME/asciinema (when $XDG_CONFIG_HOME is set) or $HOME/.config/asciinema.