tlog-play(8)

📦 version 14, in centos-stream 10, centos-stream 9, debian bookworm, fedora 43, fedora 44, ubuntu jammy, ubuntu noble, ubuntu questing, ubuntu resolute, ubuntu stonking

💖 tlog-play(8) — the System Manager's Manual glow-up 💖

okay bestie, so this is tlog-play, part of the tlog family, and it lives in section 8 of the System Manager's Manual. Think of it as the rewind button for your terminal. Let's get into it 🎀

✨ NAME ✨

tlog-play — play back terminal I/O recorded by tlog-rec(8)

🦋 SYNOPSIS 🦋

tlog-play [OPTION...]

💅 DESCRIPTION 💅

So tlog-play is the playback program for terminal I/O that got recorded with tlog-rec(8). It re-plays the recording on whatever terminal you run it under, and here's the tea: it can't change its own size. So for playback to look right, your playback terminal size has to match the recorded terminal size. No cap, that's just how it is 😭

tlog-play pulls its parameters from the system-wide config file /etc/tlog/tlog-play.conf, and you can override any of that with the command-line options listed below. Iconic behaviour, honestly.

⭐ OPTIONS ⭐

🌸 General options 🌸

  • -h, --help — prints a command-line usage message and then dips. bye ✌️
  • -v, --version — spits out version info and exits.
  • --configuration — dumps the program configuration as JSON and exits. very demure, very mindful.
  • -s, --speed=NUMBER — sets the playback speed multiplier to NUMBER.
    • NUMBER is a floating-point number, and the playback speed gets multiplied by it. You can literally adjust this mid-playback, it's giving live DJ 🎧
    • Value minimum: 0
  • -f, --follow — wait for new messages and play them back.
    • If you specify this, when playback hits the end of the recorded session it just... waits 🫶, and when new messages get added it plays them as they show up. obsessive follow energy.
  • -g, --goto=STRING — fast-forward to STRING time (start/end/HH:MM:SS.sss).
    • STRING is a logical location, or a time to fast-forward the recording to. It can be the string "start", the string "end", or a timestamp formatted as HH:MM:SS.sss, where any part can be left out to mean zero. yes bestie, you can absolutely just skip to the good part ✨
  • -p, --paused — start playback paused.
    • If specified, playback starts out in a paused state. frozen. statue. 💀
  • -r, --reader=STRING — use the STRING log reader (file/journal/es, default file).
    • STRING is the type of "log reader" used for retrieving log messages. The reader you pick has to be configured with its own dedicated parameters, so don't forget those.
    • Value should be one of: "file", "journal", "es"
  • --persist — ignore the quit key and signals from the keyboard.
    • If specified, ignore any keyboard-generated signals and the quit key. it simply will not be stopped 😤
  • --lax — ignore missing (dropped) log messages.
    • If specified, ignore missing (dropped, or lost) log messages. Otherwise it reports an error and aborts when a message is missing. so like, strict mode is the default, keep that in mind.

📁 File reader options 📁

  • -i, --file-path=FILE — read the log from the FILE file.
    • FILE is the path to the file the "file" reader should read logs from.
  • -m, --file-match=STRING — playback the explicit recording id specified in STRING.
    • STRING is the recording id of the recording the "file" reader should seek to for playback.

🔍 Elasticsearch reader options 🔍

  • --es-baseurl=STRING — Elasticsearch URL without query or fragment parts.
    • STRING is the base URL to request Elasticsearch through. Should not contain query (?...) or fragment (#...) parts.
  • --es-query=STRING — Elasticsearch query.
    • STRING is the query string to send to Elasticsearch.
  • --es-verbose — enable verbose output on the Elasticsearch HTTP client.
    • If specified, enable verbose output on the Elasticsearch HTTP client. it's giving loud and proud 📢

🗂️ Systemd journal reader options 🗂️

  • -S, --journal-since=SECONDS — start searching the journal at SECONDS since epoch.
    • SECONDS is the number of seconds since epoch to seek to before searching for the first matching log entry.
    • Value minimum: 0
  • -U, --journal-until=SECONDS — stop searching the journal at SECONDS since epoch.
    • SECONDS is the number of seconds since epoch at which searching for log entries should stop.
    • Value minimum: 0
  • -M, --journal-match=STRING — add STRING to the journal match symbol list.
  • -N, --journal-namespace=STRING — search for the records in the STRING namespace only.
    • STRING is the Specifies a specific journal namespace to use.

🎮 CONTROLS 🎮

You can drive playback with these keys, bestie. keyboard main character energy 👑

  • SPACE, p — pause/resume playback.
  • } — double the playback speed. Maximum is 16x.
  • { — halve the playback speed. Minimum is 1/16x.
  • BACKSPACE — reset playback to normal, 1x speed.
  • . — output the next packet immediately, without delay, regardless if paused or not. Press it when paused to step through the recording. Press it once to skip a long pause. Hold it to skip through the recording at constant speed (the keyboard repeat rate).
  • G — fast-forward the recording to the end, or to a specified time. Works while playing and on pause. You can specify the time by typing in a timestamp before pressing 'G'. The timestamp should follow the format of the -g/--goto option value, but without the fractions of a second. The command has no effect if the specified time location has already been reached.
    • E.g. pressing just 'G' would fast-forward to the end, which is useful with following enabled. Pressing '3', '0', 'G' (typing "30G") would fast-forward to 30 seconds from the start of the recording. Typing "30:00G" would fast-forward to 30 minutes, and so would "30:G", and "1800G". Typing "2::G" would fast-forward to two hours into the recording, the same as "120:G" and "7200G".
  • q — stop playing and quit.

🗃️ FILES 🗃️

  • /etc/tlog/tlog-play.conf — The system-wide configuration file

💀 BUGS 💀

okay so this part is important, listen up. Recordings can include control sequences attempting to communicate with the terminal, and the playback terminal would dutifully reply to them. tlog-play tries to filter these responses out, but since it's not a full terminal emulator itself, and since there's a great variety of such control sequences, it can sometimes fail, and interpret some of these as the playback control keys described above, with corresponding effects. 🫠

This is going to be fixed in future releases, possibly by embedding a proper terminal emulator in tlog-play. For now, most recordings would reproduce correctly, but some might exhibit erratic behavior, and it is possible to e.g. make a recording which would skip (hide) a part of itself on playback. However, there are other, easier ways to hide actions on a terminal, of course.

bestie. do not rely on this to hide your secrets. it's not even good at hiding them 💅

🌈 EXAMPLES 🌈

Play back contents of a file written with tlog-rec's "file" writer:

tlog-play -r file --file-path=recording.log

Play back a recording from Journal:

tlog-play -r journal -M TLOG_REC=6071524bb44d403991a00413ab7c8596-53bd-378c5d9

Play back a recording from Elasticsearch:

tlog-play -r es --es-baseurl=http://localhost:9200/tlog/tlog/_search --es-query=session:121

👀 SEE ALSO 👀

tlog-play.conf(5), tlog-rec(8)

🫶 AUTHOR 🫶

Nikolai Kondrashov <spbnick@gmail.com>

and that's the whole page, no notes 💖 this was brought to you by Tlog, dated March 2016, and yeah the date is giving vintage but the vibes are forever. mwah 💋✨

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