kv: A page viewer written in Ruby

kv is a page viewer designed for streaming data written in Ruby.

Installation

Install it yourself as:

$ gem install kv

kv requires recent Ruby and curses gem.

Use kv

# View [FILE]
$ kv [OPTIONS] [FILE]

# View [URI] source code
$ kv [URI]

# View results of [CMD]
$ [CMD] | kv [OPTIONS]

# View command help
$ kv --help

Usage: kv [options]
    -f                               following mode like "tail -f"
    -n, --line-number LINE           goto LINE
    -N                               Show lines
    -T, --time-stamp                 Enable time stamp
    -e CMD                           Run CMD as a child process
    -p, --pipe                       Open named pipe
    -s                               Separation mode (tsv)
    -w                               Watch mode: Reload on file changed
        --filter-command=FILTER_COMMAND
                                     Apply filter command

Note that --pipe option creates a named pipe (~/.kv_pipe or a specified file) if there is not a fifo file.

Command on a pager

kv: A pager by Ruby Command list

  ?: show the help message
  q: quit

  # Moving
  k, j, [UP], [DOWN]:           move cursor (y)
  h, l, [LEFT], [RIGTH]:        move cursor (x)
  Ctrl-U, [PAGE UP]:            page up
  Ctrl-D, [PAGE DOWN], [SPACE]: page down

  g: Goto first line
  G: Goto last line (current last line)
  \d+: Goto specified line

  # Loading
  You can load a huge file or infinite input from a pipe.
  10,000 lines ahead current line will be loaded.
  If you want to load further lines the follwoing commands will help you.

  F: Load remaining data or monitor a specified file and scroll forward.
     Pushing any keys stops loading.
     If a search string (specified by commadn "/") is specified,
     stop scroll if the further input lines contains the string.

  L: Toggle unlimited input mode

  # Searching
  /: search
    When you enter a search string, you can choose
    the following mode by Control key combination:
      Ctrl-R: toggle Regexp mode (Ruby's regexp)
      Ctrl-I: toggle ignore case mode
    To clear search string, research with an empty string.
  n: search next
  p: search preview
  f: filter mode (show only matched lines)

  # Output
  s: Save screen buffer to file
  P: gist -p

  # Child process
  You can run child process using -e command line option like -e CMD
  and you can send a meesage to the child process with x command.

  x: send a message to the child process

  # Modes
  N: toggle line mode
  T: toggle time stamp mode
  m: toggle mouse mode
  t: terminal (REPL) mode
  v: vi ("vi filename +[LINE]")
  H: show HTTP response header

G is notable feature, less doesn't have. This feature jumps to "current" last line even if the pipe source command does not close output (== input for kv). You can refresh the last line by putting any command.

Mouse mode

Not yet.

Terminal (REPL) mode

Not yet.

Contributing

Bug reports and pull requests are welcome on GitHub at https://github.com/ko1/kv.

Credit

Created by Koichi Sasada at 2020.