DZone Snippets: cli code

Simple way to check command line arguments in a C program

jmftrindade (Joana M. F. da Trindade) — Mon, 25 Feb 2008 22:49:18 GMT

A simple way to check command line arguments.

Author: Joana Matos Fonseca da Trindade
Date: 2008.02.25



#include 

#include 

#include 



/* minimum required number of parameters */

#define MIN_REQUIRED 2



/* display usage */

int help() {

   printf("Usage: myprogram [-s ] [-n ] [-true]\n");

   printf("\t-s: a string a\n");

   printf("\t-n: a number\n");

   printf("\t-true: a single parameter\n");



   return 1;

}



/* main */

int main(int argc, char *argv[]) {

   if (argc < MIN_REQUIRED) {

      return help();

   }

   int i;



   /* iterate over all arguments */

   for (i = 1; i < (argc - 1); i++) {

       if (strcmp("-s", argv[i]) == 0) {

          /* do something with it */ 

          printf("string = %s\n", argv[++i]);

          continue;

       }

       if (strcmp("-n", argv[i]) == 0) {

          /* do something with it. for example, convert it to an integer */

          printf("number = %i\n", atoi(argv[++i]));

          continue;

       }

       if (strcmp("-true", argv[i]) == 0) {

          printf("true activated\n");

          continue;

       }

       return help();

   }

   return 0;

}

ARGV Parser

Black_H (Black_H) — Sun, 03 Feb 2008 20:24:59 GMT

This function parse ARGV and return a string.
See exemples for more informations :

// Go : http://blackh.badfile.net/wordz/

Function :



  def options(param)

  

	i = 0

		ARGV.each  { |valeur|

		

    		if (valeur == '-' + param.to_s)

				return ARGV[i+1]

			elseif (valeur != '-' + param.to_s)

				return false

			end

		i += 1

		}

		

   end

Usage :

// cmd> ruby test.rb -o foo





	out =  self.options('o')



	if (out != false and out.empty? == false)

                   puts out # print -> foo

	end

MySQL Database Size

willcodeforfoo () — Fri, 08 Jun 2007 14:51:07 GMT

mysql -uroot -D sfcnet_development -e "show table status\G"| egrep "(Index|Data)_length" | awk 'BEGIN { rsum = 0 } { rsum += $2 } END { print rsum }'

Mount SSH using MacFUSE

willcodeforfoo () — Sun, 21 Jan 2007 23:14:06 GMT

This will also list the voume in the Finder, thanks to the volname option (I think)

mkdir -p ~/mnts/formandfx

sshfs kmarsh@formandfx.com: ~/mnts/formandfx -oping_diskarb,volname=formandfx

Bandwidth Monitoring From the Console Using 'pktstat'

nihilist (David) — Wed, 01 Feb 2006 01:30:18 GMT

Pktstat, http://www.adaptive-enterprises.com.au/~d/software/pktstat/, displays a real-time summary of packet activity on an interface. Each line displays the data rate associated with a particular class of packets. The class is determined by the packet header.

For example, 'pktstat -w1' will refresh once per second showing the average bandwidth usage and active connections:



# pktstat -w1



  interface: eth0 

  load averages: 285.9k 167.3k 67.3k bps 



    bps    % desc 

  466.8   0% arp 

             tcp 205.188.1.192:5190 <-> c-24-21-74-176:1472 

   6.0k   0% tcp c-24-21-74-176:3933 <-> host75:3724 

  63.5k   1% tcp c-24-21-74-176:4662 <-> p50906304:61951 

  27.4k   0% udp 10.141.192.1:bootps <-> 255.255.255.255:bootpc

Correcting a command

nihilist (David) — Wed, 01 Feb 2006 01:27:28 GMT

If you've run a command that you discover needs a path, you can do something like this on the following line:



$ psql -U postgres mydb_here

bash: psql: command not found



$ /usr/local/pgsql/bin/!!

/usr/local/pgsql/bin/psql -U postgres mydb_here



Welcome to psql 7.3.5, the PostgreSQL interactive terminal.

mydb_here=#

Or if you mistyped the path:



$ /usr/loca/pgsql/bin/psql -U postgres mydb_here

-bash: /usr/loca/pgsql/bin/psql: No such file or directory



$ ^loca^local

usr/local/pgsql/bin/psql -U postgres mydb_here



Welcome to psql 7.3.5, the PostgreSQL interactive terminal.

mydb_here=#

Model, View, Controller HOWTO

kbrooks () — Wed, 04 Jan 2006 15:19:01 GMT

MVC howto
Original vrsion can be found at http://kbrooks.ath.cx/mvchowto/intro.py



#!/usr/bin/python



# MVC Howto - Introduction & code

# What is "MVC"?

#   MVC stands for "Model", "View" & "Controller", a way of seperating your code into

#   manageable and independent chunks that can be changed easily.

# Why use MVC?

#   Because code is independent from each other, it becomes easier for you to change part of the code to do what you want.

#   For example, you could change where data is shown without changing anything else!

# Copyright (c) 2006 Kyle Brooks. Licensed under the Creative Commons Attribution License.

# We will be creating a command line calculator in this HOWTO.

import sys

# Model: a object that interfaces with the real world and returns information.



class Model:

    def calculate(self, left, op, right):

        if op == "+":

            return left + right

        elif op == "-":

            return left - right

# As you see in the code above, the model has the action "calculate".



# View: a object that gets passed the result from the model via the controller. Displays data.

class View:

    def display_data(self, result):

        print result

# As you see in the code above, ALL the view does is display data from the controller.



# Controller: a object that holds a reference to the model and view. Communicates with the model and view. Handles data from the user.

class Controller:

    operands = ["+", "-"]

    def __init__(self, model, view):

        self.model = model

        self.view = view

    def run(self):

        sys.stdout.write(">> ")

        sys.stdout.flush()

        # read a line

        line = sys.stdin.readline()

        line = line.strip()

        if line == "":

            sys.stdout.write("\n>> ")

            sys.stdout.flush()

            return

        for operand in self.operands:

            larray = line.split(operand)

            if larray[0] == line:

                continue

            else:

                break

        else:

            sys.stdout.write("NaN\n")

            sys.stdout.flush()

            return

        larray[0] = int(larray[0])

        larray[2] = int(larray[0])

        result = self.model.calculate(*larray)

        self.view.display_data(result)

Testã? ã‚ˆï½ž

test1111 (test1111) — Thu, 24 Nov 2005 16:13:50 GMT

arectwevw

Mail a file as an attachment from the UNIX prompt

peter (Peter Cooperx) — Mon, 22 Aug 2005 03:34:44 GMT

uuencode file.txt file.txt | mail email@address.com

Easy file encryption and decryption from the shell

peter (Peter Cooperx) — Fri, 27 May 2005 11:17:25 GMT

Works on OS X, Linux, anywhere with OpenSSL installed:

To encrypt a file:
openssl des3 -salt -in infile.txt -out encryptedfile.txt

To decrypt the file:
openssl des3 -d -salt -in encryptedfile.txt -out normalfile.txt

Do not specify the same file as input and output on encryption.. I have noticed weird effects on OS X (it eats the file). Remove the -in * stuff if you want to pipe data into it (e.g. a tarred folder). Omit the -out * stuff if you want it to pipe data out on STDOUT.