grep每隔X分钟记录最后X分钟

Question

我想每隔X分钟grep一次最后X分钟的日志（例如：每5分钟最后5分钟的grep日志），而不是更老的东西。最简单的方法是什么？

Answer 1

Ruby 1.9.3解决方案

你需要的第二部分，我还没有测试过它:(

注意：如果您知道＆＃39; ruby​​＆＃39;的位置。改变shebang（脚本的第一行）， 出于安全考虑。

#! /usr/bin/env ruby

require 'date'
require 'pathname'

if ARGV.length != 4
        $stderr.print "usage: #{$0} -d|-h|-m|-s time expression log_file\n"
        exit 1
end
begin
        total_amount = Integer ARGV[1]
rescue ArgumentError
        $stderr.print "error: parameter 'time' must be an Integer\n"
        $stderr.print "usage: #{$0} -d|-h|-m|-s time expression log_file\n"
end

if ARGV[0] == "-m"
        gap = Rational(60, 86400)
        time_str = "%b %d %H:%M"
        until_next_search = total_amount * 60
elsif ARGV[0] == "-s"
        gap = Rational(1, 86400)
        time_str = "%b %d %H:%M:%S"
        until_next_search = total_amount 
elsif ARGV[0] == "-h"
        gap = Rational(3600, 86400)
        time_str = "%b %d %H"
        until_next_search = total_amount * 3600
elsif ARGV[0] == "-d"
        time_str = "%b %d"
        gap = 1
        until_next_search = total_amount * 86400
else
        $stderr.print "usage: #{$0} -d|-h|-m|-s time expression log_file\n"
        exit 1
end

pn = Pathname.new(ARGV[3])
if pn.exist?
        log = (pn.directory?) ? ARGV[3] + "/*" : ARGV[3]
else
        $stderr.print "error: file '" << ARGV[3] << "' does not exist\n"
        $stderr.print "usage: #{$0} -d|-h|-m|-s time expression log_file\n"
end

search_str = ARGV[2]
now = DateTime.now

while true
        total_amount.times do
                now -= gap
                system "cat " << log << " | grep '" << now.strftime(time_str) << ".*" << search_str << "'"
        end
        sleep until_next_search
end