DZone Snippets: unix code

Inspect a website like a string in Ruby

ntk () — Wed, 09 Jul 2008 21:13:48 GMT

Put the following function into your ~/.bash_login (or alternatives).



unset -f inspect_url



function inspect_url() { 

   /usr/bin/curl -L -s --max-time 10 "${@}" | ruby -n -e 'p $_.to_s'

   return 0

}



inspect_url http://www.ruby-forum.com

Compile & install Nginx web server

ntk () — Wed, 18 Jun 2008 20:03:18 GMT

Requirement on Mac OS X: Xcode



# See:

# - http://en.wikipedia.org/wiki/Nginx

# - http://wiki.codemongers.com/NginxGettingStarted

# - http://wiki.codemongers.com/NginxInstallOptions

# - http://wiki.codemongers.com/NginxCommandLine

# - http://wiki.codemongers.com/NginxConfiguration



export PATH="/usr/local/bin:/usr/local/sbin:/usr/bin:/bin:/usr/sbin:/sbin"



mkdir -p ~/Desktop/Nginx

cd ~/Desktop/Nginx



curl -L -O http://sysoev.ru/nginx/nginx-0.7.2.tar.gz

tar -xzf nginx-0.7.2.tar.gz



curl -L -O http://downloads.sourceforge.net/pcre/pcre-7.7.tar.gz

tar -xzf pcre-7.7.tar.gz



cd ~/Desktop/Nginx/nginx-0.7.2

./configure --help

./configure --prefix=/usr/local/nginx --sbin-path=/usr/local/sbin --with-debug --with-http_ssl_module --with-pcre=../pcre-7.7

make

sudo make install





which nginx

otool -L /usr/local/sbin/nginx

open /usr/local/nginx

open -e /usr/local/nginx/conf/nginx.conf



nginx -v

nginx -V

sudo nginx   # start server

sudo nginx -t



open http://localhost:80

open http://localhost:80/50x.html



sudo nano /usr/local/nginx/conf/nginx.conf   # editing ... server {  listen  8080; ... 



# reload configuration

sudo kill -HUP `cat /usr/local/nginx/logs/nginx.pid`  



# stop server

sudo kill -15 $(ps -auxxx | egrep "[n]ginx.*master" | awk '{ print $2 }') 2>/dev/null

Shell script to make lists of certain file types in a web site file system

johnloy (John Loy) — Sat, 31 May 2008 20:00:15 GMT

mkdir file_lists
find . -name '*.pdf' -o -name '*.PDF' > ./file_lists/all_pdf_files.txt
find . -name '*.pdf' -o -name '*.PDF' -mtime +365 > ./file_lists/pdf_files_mtime_gt_1yr.txt

find . -name '*.jpg' -o -name '*.JPG' -o -name '*.gif' -o -name '*.GIF' -o -name '*.png' -o -name '*.PNG' > ./file_lists/all_image_files.txt

find . -name '*.log' -o -name '*.LOG' > ./file_lists/all_log_files.txt

find . -name '*.css' -o -name '*.CSS' -o -name '*.js' -o -name '*.JS' > ./file_lists/all_design_assets_files.txt

find . -name '*.ram' -o -name '*.RAM' -o -name '*.aif' -o -name '*.AIF' -o -name '*.mp3' -o -name '*.MP3' > ./file_lists/all_audio_files.txt
find . -name '*.ram' -o -name '*.RAM' -o -name '*.aif' -o -name '*.AIF' -o -name '*.mp3' -o -name '*.MP3' -mtime +365 > ./file_lists/audio_files_mtime_gt_1yr.txt

find . -name '*.html' -o -name '*.HTML' -o -name '*.htm' -o -name '*.HTM' > ./file_lists/all_html_files.txt
find . -name '*.html' -o -name '*.HTML' -o -name '*.htm' -o -name '*.HTM' -mtime +365 > ./file_lists/html_files_mtime_gt_1yr.txt

Inplace substitutions

remvee (Remco van 't Veer) — Wed, 28 May 2008 07:52:09 GMT

Place all occurrences of "old value" with "new value" in all txt files.



ruby -p -i -e '$_.gsub!("old value", "new value")' *.txt

One-line web server in Ruby

ntk () — Wed, 23 Apr 2008 13:22:36 GMT





# From: http://www.ntecs.de/blog/articles/2008/02/09/the-worlds-smallest-webserver

# Author: Michael Neumann

# ... point your browser to http://localhost:3125/etc/motd



ruby -rsocket -e 's=TCPServer.new(5**5);loop{_=s.accept;_<<"HTTP/1.0 200 OK\r\n\r\n#{File.read(_.gets.split[1])rescue nil}";_.close}'

process email files like unix find

nicferrier (Nic Ferrier) — Tue, 18 Mar 2008 16:54:19 GMT

I call this program whitelist. It lets you run a command on a bunch of files depending on whether the file is an email and has a from address in a whitelist.

It's useful for maintaining whitelisted mailboxes and analysing mailboxes. With a few more tests it might be a generically useful tool.



#!/usr/bin/python

# Copyright (C) 2008 by Tapsell-Ferrier Limited



# This program is free software; you can redistribute it and/or modify

# it under the terms of the GNU General Public License as published by

# the Free Software Foundation; either version 2, or (at your option)

# any later version.



# This program is distributed in the hope that it will be useful,

# but WITHOUT ANY WARRANTY; without even the implied warranty of

# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the

# GNU General Public License for more details.



# You should have received a copy of the GNU General Public License

# along with this program; see the file COPYING.  If not, write to the

# Free Software Foundation, Inc.,   51 Franklin Street, Fifth Floor,

# Boston, MA  02110-1301  USA



import commands

import email.Parser

import sys

import re

import getopt

import os

import os.path



try:

    from email.utils import parseaddr

except:

    from rfc822 import parseaddr





def help():

    print """whitelist.py -h

whitelist.py [-v] [-f whitelist filename] command ; filelist [-]



Execute the specified command (which must be shell escaped if calling

from shell) on all the files in the filelist or, if - is present in

the filelist, read from stdin (like xargs) whenever the file is an

email that contains a from address specified in the whitelist.



Like xargs, or find, the command can include {} as a replacement token

for the matched filename.



The command can also be a header reference, for example:



  $FROM



will print the specified mails From address.



Options:



 -v   specifies that the test is to be negated, executing the action if

      the file does NOT contain a from address in the whiltelist.



 -f   specifies a whitelist, the default is $HOME/.addresses



For example:



 whitelist.py -f .wlist wc \{} \: maildir/cur/*



runs wc on each file in maildir/cur with a FROM address matching

something in the whitelist; or:



 find maildir/INBOX/cur -type f | whitelist.py -v mv \{} mailbox/TRASH/cur \; -



mv's all files in the INBOX with FROMs not matching the whitelist into

a TRASH folder.



  find maildir/Greylist/new -type f | whitelist.py -v $TO \; -



displays the TO address of all messages where the from didn't match

the whitelist.

"""





def read_whitelisted(filename):

    fd = open(filename)

    data = fd.read()

    fd.close()

    return data.split()



def get_msg(filename):

    fd = open(filename)

    try:

        msg = email.Parser.HeaderParser().parse(fd, True)

        return msg

    finally:

        fd.close()



action_re = re.compile("\{}")



def handle(filenames_fn, action, whitelist, negate=False):

    for filename in filenames_fn():

        msg = get_msg(filename)

        realname, addr = parseaddr(msg["from"])

        result = addr in whitelist



        if negate:

            result = not result



        if result:

            try:

                m = re.match("\$(.+)", action)

                result = msg[m.group(1)]

            except Exception:

                cmd_str = action_re.sub(filename, action)

                os.system(cmd_str)

            else:

                print result





def main(args):

    negate = False

    whitelist_filename = os.path.join(os.environ["HOME"], ".addresses")

    opts, args = getopt.getopt(args, "hv")

    for o,a in opts:

        if o == "-h":

            help()

            sys.exit(0)



        elif o == "-v":

            negate = True



        elif o == "-f":

            whitelist_filename = a



    if not os.access(whitelist_filename, os.F_OK):

        print >>sys.stderr, "whitelist.py   -  no whitelist filename\n"

        help()

        sys.exit(1)



    cmdstr = " ".join(args)

    m = re.match("(.*) ;([ ]*.*)", cmdstr)

    if not m:

        sys.exit(1)



    cmd = m.group(1)

    files = m.group(2).strip().split(" ")



    def ffn():

        for f in files:

            if f == "-":

                for innerf in sys.stdin:

                    yield innerf.strip()

            else:

                yield f

        return



    whitelist = read_whitelisted(whitelist_filename)

    handle(ffn, cmd, whitelist, negate)





if __name__ == "__main__":

    main(sys.argv[1:])



# End

Morse decode using sed

scvalex (Alexandru Scvortov) — Fri, 15 Feb 2008 13:54:22 GMT

This is a short Morse code decoder written as a shellscript using sed.

The Morse coded text should be in $text, and should be written with spaces between the letters.



echo $text\  | tr . 0 | sed -e {s/0----\ /1/g} -e {s/00---\ /2/g} -e {s/000--\ /3/g} -e {s/000-\ /4/g} -e {s/00000\ /5/g} -e {s/-0000\ /6/g} -e {s/--000\ /7/g} -e {s/---00\ /8/g} -e {s/----0\ /9/g} -e {s/-----\ /0/g} \

	| sed -e {s/-0-0\ /c/g} -e {s/-000\ /b/g} -e {s/00-0\ /f/g} -e {s/0000\ /h/g} -e {s/0---\ /j/g} -e {s/0-00\ /l/g} -e {s/0--0\ /p/g} -e {s/--0-\ /q/g} -e {s/000-\ /v/g} -e {s/-00-\ /x/g} -e {s/-0--\ /y/g} -e {s/--00\ /z/g} \

	| sed -e {s/0--\ /w/g} -e {s/-00\ /d/g} -e {s/--0\ /g/g} -e {s/-0-\ /k/g} -e {s/---\ /o/g} -e {s/0-0\ /r/g} -e {s/000\ /s/g} -e {s/00-\ /u/g} \

	| sed -e {s/0-\ /a/g} -e {s/00\ /i/g} -e {s/--\ /m/g} -e {s/-0\ /n/g} \

	| sed -e {s/0\ /e/g} -e {s/-\ /t/g}

Untill keypressed / conio.h

ptr128 (Mariusz) — Wed, 23 Jan 2008 03:29:25 GMT

Turbo Pascal and conio.h allowed immediate character reading, without wainting for enter. Following code does the same under unix terminals:



#include 

#include 



char getch(void) {

        char buf = 0;

        struct termios old = {0};

        if (tcgetattr(0, &old) < 0)

                perror("tcsetattr()");

        old.c_lflag &= ~ICANON;

        old.c_lflag &= ~ECHO;

        old.c_cc[VMIN] = 1;

        old.c_cc[VTIME] = 0;

        if (tcsetattr(0, TCSANOW, &old) < 0)

                perror("tcsetattr ICANON");

        if (read(0, &buf, 1) < 0)

                perror ("read()");

        old.c_lflag |= ICANON;

        old.c_lflag |= ECHO;

        if (tcsetattr(0, TCSADRAIN, &old) < 0)

                perror ("tcsetattr ~ICANON");

        return (buf);

}



int main() {

        char key;

        printf("Press 'x' to exit...\n");

        while((key=getch()) && (key != 'x'))

                printf ("you pressed %c\n", key);

        return(0);

}

Unix Console Styler

kedare (Mathieu Poussin) — Wed, 28 Nov 2007 19:21:49 GMT

This modue can be used to apply many style on Unix* terminals



# Unix Console Style

# You can use this module to apply a style on the terminal

#

# DON'T WORK ON WINDOWS (Only on *nix Terminal)



module UnixConsoleStyler

  class StyleNotFoundException < Exception; end

  

  # Availables Styles

  STYLE = {

      :default    =>    "\033[0m",

    	# styles

    	:bold       =>    "\033[1m",

    	:underline  =>    "\033[4m",

    	:blink      =>    "\033[5m",

    	:reverse    =>    "\033[7m",

    	:concealed  =>    "\033[8m",

    	# font colors

    	:black      =>    "\033[30m", 

    	:red        =>    "\033[31m",

    	:green      =>    "\033[32m",

    	:yellow     =>    "\033[33m",

    	:blue       =>    "\033[34m",

    	:magenta    =>    "\033[35m",

    	:cyan       =>    "\033[36m",

    	:white      =>    "\033[37m",

    	# background colors

    	:on_black   =>    "\033[40m", 

    	:on_red     =>    "\033[41m",

    	:on_green   =>    "\033[42m",

    	:on_yellow  =>    "\033[43m",

    	:on_blue    =>    "\033[44m",

    	:on_magenta =>    "\033[45m",

    	:on_cyan    =>    "\033[46m",

    	:on_white   =>    "\033[47m" }

  

  # Methods to use if you want to apply a style

  def UnixConsoleStyler::apply_style(style)

    if STYLE.has_key? style

      STDOUT.write STYLE[style]

    else

      raise StyleNotFoundException, "Style #{style} not found"

    end

  end

  

end

Unix shell script providing Ruby on Rails enhanced String methods

HotFusionMan (Al Chou) — Sun, 18 Nov 2007 04:49:21 GMT

Assuming you have Rails installed as a gem, the following Unix shell script (which I named String, but you can name anything you want when you save the following into a file) allows you to call Ruby String methods (including, importantly, the methods that the Rails ActiveSupport extensions add) on an arbitrary number of arguments, and it will print out the results, e.g.,

$ String camelize snake_case_example another_snake_case_example

The output is:

SnakeCaseExample
AnotherSnakeCaseExample



#!/usr/bin/env ruby



if ARGV.size > 1 then

  gem 'activesupport'

  require 'active_support/core_ext/string/inflections'



  class String

    include ActiveSupport::CoreExtensions::String::Inflections

  end



  command = ARGV.shift

  ARGV.each { |argument|

    puts argument.send( command )

  }

else

  # Print usage information

  puts "Usage: #{File.basename( __FILE__ )}   [ ...]"

end