Settings

Edit → Settings… (Ctrl+,), or Logsift → Settings on macOS (⌘,). Changes apply at once. Four tabs: General, Log Formats, Source Code, Agents.

General

Setting	Default	What it does
Font and size	Automatic (the first installed of JetBrains Mono, Cascadia Mono, Consolas, Menlo, SF Mono, DejaVu Sans Mono, Liberation Mono, Ubuntu Mono), 13	The font of logs. Ctrl+= / Ctrl+- also change the size
Tab width	4	How wide a tab character is
Stripe every other line	on	A faint stripe on every other line (also View → Line Stripes)
Show the timeline	on	The timeline above logs
Dark mode	off	Also View → Dark Mode
Text that isn’t UTF-8	Windows-1252	How to read files that aren’t UTF-8 or UTF-16 (Latin-1, Cyrillic, Shift_JIS, EUC-JP, GB18030, Big5, EUC-KR, KOI8-R…). View → Encoding changes it for one file
Check files for changes	Twice a second	Less often uses less power with many open files, or files on network drives
Two files dropped	Ask each time	Two files dropped on the window: ask, compare them, or open each in its own tab
At start: Reopen the files that were open last time	on	Reopens the last session when Logsift starts without a file
Check for new versions once a day	on	Asks GitHub for the latest version number only; nothing about you or your logs is sent. A button appears in the status bar when a new version is out

Log formats

When Logsift doesn’t know a log’s layout, the Columns view says so and offers Define Its Format…. Formats are also under View → Log Format → New Format from This Log…. There are three ways to make one:

Drop a log file here (or Open a Log File…). Logsift guesses the layout from its lines (time, level, [thread], logger, separators) and how its times are written.
Or paste how your program logs, then Create Format: a log4j, Log4j 2 or logback pattern such as %d{HH:mm:ss.SSS} [%thread] %-5level %logger{36} - %msg%n, a whole logback.xml, log4j2.xml or log4j.properties, Spring Boot’s layout, a java.util.logging SimpleFormatter.format, or a Python logging format, logging.conf or basicConfig(…). When a config has several layouts, each becomes a format.
Write a Pattern Yourself…: {time} {level} [{thread}] {logger} - {message}. Columns go in braces; everything else is matched as written. {*} skips a part. A regex with named groups like (?<level>…) works too.

Each format has a Name, a Line pattern, a Time format (empty for any common timestamp), and Always use for (file names like app*.log; *.trace). A preview shows sample lines split into columns.

A format is used when most of a log’s lines fit it, or always for the file names you give. The log’s bar shows the format each log is read with (Format: …▾, on the right); click it to choose another for that file, or Plain text. Levels in your format’s level column drive the colours, the error marks and the E W I D T buttons.

Formats are saved in ~/.logsift/formats.properties; copy it to use them on another computer.

Source code

For opening a stack frame in your editor (see Exceptions):

Source folders: your projects’ source code. Add Folder…, Remove.
Open with: Automatic (IntelliJ IDEA or PyCharm when installed, else Visual Studio Code), IntelliJ IDEA, PyCharm, Visual Studio Code, The system’s app for the file (without the line), or My own command.
Command (for My own command): for example myeditor --goto {file}:{line}. {file} and {line} are filled in; put quotes around a path with spaces.

Other settings in the menus

Help → Check for Updates Automatically: the same as the update setting above.
View → Encoding: reopens one log in another encoding.
View → Log Format: the format for one log.
Each log’s view buttons (Wrap, Columns, Tree, Timeline, Follow, Reload Automatically) are remembered as the default for the next log you open.

Where Logsift keeps its files

In ~/.logsift (your home folder):

File or folder	Holds
`formats.properties`	Your log formats
`files/`	What each log remembers: filters, position, view
`bookmarks/`	Bookmarks and their notes
`errors.log`	Unexpected errors, every session (Help → Open Error Log; this session’s in Help → Show Errors…)
`stdin/`	Piped output, kept a week
`heap-index/`	Indexes of big heap dumps, removed when their tab closes
`agent.properties`	Settings → Agents: what is masked, which folders agents may read
`agent.log`	Each call coding agents made (never the answers)

Other preferences (window size, recent files, last folders, servers and users, never passwords) are kept in Java’s preferences store for your user.

Logsift never sends your logs anywhere. Its only network connections are the daily update check (if on) and the servers you choose: SSH servers, JMX ports, and web addresses you open. When you set up a coding agent, what Logsift answers it goes to the agent’s AI provider.

Agents

How to let a coding agent such as GitHub Copilot ask Logsift about your logs, what is masked in its answers, and which folders it may read. See Coding agents.

← All guide pages