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|
#!/usr/bin/env ruby
require "curses"
include Curses
unless ARGV.size == 1
puts "usage: #{$0} file"
exit
end
begin
data_lines = File.readlines(ARGV[0])
rescue
raise "cannot open file: #{ARGV[0]}"
end
init_screen
#keypad(stdscr, true)
nonl
cbreak
noecho
#scrollok(stdscr, true)
lptr = 0
loop do
lines.times do |i|
setpos(i, 0)
#clrtoeol
addstr(data_lines[lptr + i] || "")
end
refresh
explicit = false
n = 0
c = nil
loop do
c = getch
if c =~ /[0-9]/
n = 10 * n + c.to_i
explicit = true
else
break
end
end
n = 1 if !explicit && n == 0
case c
when "n" #when KEY_DOWN
i = 0
n.times do
if lptr + lines < data_lines.size
lptr += 1
else
break
end
i += 1
end
#wscrl(i)
when "p" #when KEY_UP
i = 0
n.times do
if lptr > 0
lptr -= 1
else
break
end
i += 1
end
#wscrl(-i)
when "q"
break
end
end
close_screen
|
