comb

A small, fast terminal log viewer in plain C; libc only.

When lnav is too much, and you'd like a bit more than less.

Features

• severity highlighting (FATAL/PANIC/CRIT magenta, ERROR red, WARN yellow, DEBUG/TRACE dim)
• colored highlighting: a loose heuristic tries its best to pick up common patterns in logs and applies a rotating color palette to make it easier to parse and read
• incremental / filter: literal by default with smart case; ^/$ anchor to line start/end; Ctrl-R in the prompt switches to POSIX ERE, Ctrl-V excludes matching lines instead (grep -v). Simple alternations of plain literals run on the SIMD literal path
• highlight-only search: \ colors matches in place without narrowing; n/N jump between them
• live follow with poll(), handles file truncation/rotation
• w toggles soft line wrap (h/l/$ horizontal scrolling applies when wrap is off)
• mark lines with Space (x unmarks), copy them all with c/y via OSC 52 (works over ssh); falls back to xclip / wl-copy / pbcopy / termux-clipboard-set
• survives file truncation and rotation

Build & install

make
make install        # to /usr/local/bin (PREFIX=... to change)

This also installs the manual page (man comb).

Usage

comb [-e REGEX] [-t N] [--color=MODE] [FILE]

Reads FILE or piped/redirected stdin. Plain text only. For systemd journal or compressed logs, pipe them:

journalctl -o short-precise | comb, zcat error.log.gz | comb

Documentation

More info is included in the manual:

man comb

While running, Ctrl-h shows a compact in-program version of the key reference.

Config

Comb has no runtime configuration, but various things like keybinds or colors are easily changeable via config.h.

Tests

make check                                  # selftests + behavior assertions
python3 tests/harness.py --check ./comb     # end-to-end assertions (pty)
python3 tests/harness.py --compare OLD NEW  # byte-diff two builds

License

0BSD (see LICENSE).