Upgrade to Fedora 17 from 16.

As usual time in couple of days to upgrade to Fedora 17. Release schedule is for 05/22 and so its just around the corner. So, if you are looking at upgrading using yum, then make sure that you visit this page.

There are some changes in latest version that will not allow you to upgrade without executing few commands manually and that page lists them. And if you are too brave and just want the steps and the command then here it is:

Array of all possible colors in bash script

Sometime back, we had looked at using colors in bash script and here is a way to create a array of all the colors.

#!/bin/bash - 
#===============================================================================
#
#          FILE:  colorarray.sh
# 
#         USAGE:  ./colorarray.sh 
# 
#   DESCRIPTION:  
# 
#       OPTIONS:  ---
#  REQUIREMENTS:  ---
#          BUGS:  ---
#         NOTES:  ---
#        AUTHOR: Amit Agarwal (aka), amit.agarwal@roamware.com
#       COMPANY: Roamware India Pvt Ltd
#       CREATED: 16/04/12 17:24:09 IST
# Last modified: Mon Apr 16, 2012  05:39PM
#      REVISION:  ---
#===============================================================================
count=0
for i in 40m 41m 42m 43m 44m 45m 46m 47m
do
    for l in 0 1
    do
        echo -n "l=$l "
        for k in 0 1
        do
            # echo -n "k=$k "
            for j in {30..37}
            do
                carr[$count]="\033[$k;$j;$l;$i"
                echo -ne "${carr[$count]}$count \033[00m"
                ((count++))
            done
        done
        echo
    done
    echo
done

You can add this script to any script of your choice and you have all the 256 colors available to you in the script without additional coding. Happy coding.

Display X applications from virtual terminals

Here is a script that can help you set the proper envirionment to start a gnome-shell from one of the terminals.

#!/bin/bash - 
#===============================================================================
#
# FILE: xenv.sh
# 
# USAGE: ./xenv.sh 
# 
# DESCRIPTION: http://live.gnome.org/GnomeShell/Debugging
#
# 
# OPTIONS: ---
# REQUIREMENTS: ---
# BUGS: ---
# NOTES: ---
# AUTHOR: Amit Agarwal (aka), amit.agarwal@roamware.com
# CREATED: 09/14/2011 04:45:31 PM IST
# Last modified: Wed Sep 14, 2011 04:45PM
# REVISION: ---
#===============================================================================

gnome_session=$(pgrep -u $USER gnome-session)
eval export$(sed's/\o000/\n/g;' < /proc/$gnome_session/environ |grep DISPLAY)
eval export$(sed's/\o000/\n/g;' < /proc/$gnome_session/environ |grep XAUTHORITY)
eval export$(sed's/\o000/\n/g;' < /proc/$gnome_session/environ |grep DBUS_SESSION_BUS_ADDRESS)

So, once you have done that you have the correct environment to use the X display and thus you can start the gnome-shell as well or do any other fancy thing that you want 🙂

colors in bash scripts

I have been trying to understand the color codes for bash for a pretty long time, but somehow never got time to understand this clearly. So this time around when I was writing a script to analyze some logs. I thought I will give it a go and finally understood some part of this.

So, first we will start with this script. This is taken from here.

systemadm – simpler way to manage the service files for systemd

Once the systemd unit and service files have come into being, understanding of the system services have changed a little bit and it might require some time to understand the cli tools for managing these services and units. That being the case, systemadm comes to rescue. This is a simple tool which :

Graphical front-end for systemd.

For installation :

sudo yum install systemd-gtk

And here’s a screenshot::

Convert string to hex.

If you want to use snoop or tcpdump with advanced search in the packet, then you would need to convert the string to hex string. For this, either you can use a web search and find some web application to do that or you can use a simple C program like this 🙂

/*
* =====================================================================================
*
*       Filename:  ascii.c
*
*    Description:  ascii to dec
*
*        Version:  1.0
*        Ceated:  03/02/2012 12:08:49 PM
*       Revision:  none
*       Compiler:  gcc
*
*         Author:  Amit Agarwal (aka), amit.agarwal@roamware.com
*  Last modified: Thu Mar 08, 2012  08:47PM
*
* =====================================================================================
*/
void main (int argc, char **argv){
    int i=0;
    char a[200]="",b[200]="";
    printf("String - %s, Length - %d\n",argv[1],strlen(argv[1]));
    /*printf("%x\n 0x",argv[1]);*/
    while (i < strlen(argv[1])){
        /*printf("%c",argv[1][i]);*/
        sprintf(a,"%s%x",a,argv[1][i]);
        /*printf("a=%s\n",a);
        printf("b=%s\n",b);*/
        sprintf(b,"%s%d",b,argv[1][i]);
        i++;
    }
    printf ("\n");
    printf ("String : %s\n",argv[1]);
    printf ("Hex    : 0x%s\n", a);
    printf ("Dec    : %s\n", b);

}

Related articles

• Re: iis bug (seclists.org)
• Problem of file transfer in socket programming (daniweb.com)
• [Unix C] ECHO Implementation (jetcracker.wordpress.com)
• Character Stuffing in C (sourcecode4all.wordpress.com)

Your own local search engine.

There are times when you would want to have a local search engine capable of indexing even pdf and doc files. So here is a solution.

You can use “Omega” and here are the instructions.

download omega from http:// xapian.org/download

yum install xapian libuuid-devel

And then make and install omega and for this you can follow the instructions.

Create index using command omindex
and then you can use quest or search.py to search or you can setup the cgi way so that you can use local browser to search.