rog

Halfway between tail -f and lnav. A log reader for filtering, monitoring, and serving log data.

Modes

• Tail mode — Monitor files in real-time: rog app.log error.log
• FIFO mode — Create and read from a named pipe: rog -f /tmp/myfifo. Useful with server mode.
• Server mode — Read from any source and serve over TCP to clients: some_program | rog -s or rog -s -f /tmp/myfifo
• Client mode — Connect to a rog server: rog -k (localhost) or rog -I 10.0.0.4

Filtering

• -g REGEX — Only show matching lines
• -w REGEX — Whole-word matching
• -v REGEX — Invert match (show non-matching lines)
• -i — Case-insensitive matching
• -C NUM / -A NUM / -B NUM — Context lines around matches

Formatting

• -r F1,F2,... — Remove fields matching key=value from output
• -m THEME — Syntax highlighting theme (13 themes available; use -c to disable)
• -u — Truncate lines to terminal width
• -o NUM — Limit bytes per row

Other Options

• -d PORT — TCP port (default: 19888)
• -x REGEX — Exclude files matching pattern
• -H — Parse tail-style headers (==> file <==) in stdin/socket input
• -p CHARS — Use preset args from ~/.config/rogrc
• -P — Skip loading presets

Examples

# Tail multiple files, grep for errors with context
rog *.log -g "^ERROR" -C3

# Pipe output through server, connect remotely
some_program | rog -s
rog -I 10.0.0.4

# Create a FIFO and tail it
rog -f /tmp/myfifo
# Then: echo "log line" > /tmp/myfifo

# Remove sensitive fields while monitoring
rog app.log -r password,token -m Nord

Config

Config at ~/.config/rogrc. Lines follow the format key = args, where key can be:

• default — Always applied
• A log filename — Applied when that file is passed as an argument
• A single letter — Invoked with -p (e.g., -p ab combines presets a and b)

default = -m Dracula -u
myapp.log = -g "^ERROR|^WARN" -C2
a = /var/log/app.log
b = -Hk

Sudo / Doas

When run under sudo or doas, rog resolves the invoking user's home directory (via SUDO_USER and /etc/passwd) so that ~/.config/rogrc is read from your own home, not root's.

For doas to work correctly, add the following to /etc/doas.conf:

setenv SUDO_USER $LOGIN

Build

cargo build --release

Static binary (musl)

pacman -S musl
rustup target add x86_64-unknown-linux-musl
cargo build --release --target x86_64-unknown-linux-musl

Debug logging

cargo build --features debug_log

Tests

cargo test