There are more than 400 replies and most of its content is “please send me the project report to my email address”.

jMail++ is a webmail written in JSP. You can create new Account here like yahoo, gmail etc…The Session is handled by Single page Auto Invalidate Method..That will increase Your Mail Security. A simple 4 entry Registration process is required.. And your Password will be handle using RSA Encryption method…There is a Fast Search Mechanism included with Google APIs. The Very Important and Unique Feature is You can Check Your Rediff, Hotmail , Gmail account from this Webmail without login into the respective sites. It means this Webpage act as an Email Client Also (Like OutLook Express). The Protocols (SMTP,POP3) all are implement from Scrach without any API’s…Its is a Pure JSP Project.

This was the post on ProjectGuidance.com

Here i included the full project report as zip file.

Jmail-Project-Report.zip

See screen short of this project:

(Screenshot 1)

(Screen shot 2)

The most interesting and useful command i ever used is tail in unix. As the name indicate its duty is to show the last lines of a particular file. When take the case of log files such as error logs, always we have to know the last lines or last updations instead of reading from top to bottom or search a full text file.

for its option try this tail –help

tail -n 10 error.log

shows last 10 lines of error.log

The very interesting option is -f , means open the file and follow the last lines.

This is very useful for debugging purpose. For example if you want to check error.log lively, use this option

tail -f error.log

it displays last lines and also automatically updates when any changes happens in error.log file. So you can check other operation by tailing and following a particular file .

Try today itself. You will be very much interested, thats my guarantee

(There is also a similar function ‘head’, you can guess what its use, google it for more)

Regards

Sajith

Steps:

1) sudo apt-get install ntfs-3g

Installs ntfs-3g library
2) sudo fdisk -l

Shows all the disk drives
3) sudo mkdir /media/windowsC

Create a directory for mounting your NTFS file system

4) sudo cp /etc/fstab /etc/fstab.bak

Take a backup of old conf file

5) gksudo gedit /etc/fstab

Edit the configuration file

6) /dev/sda2 /media/windowsC ntfs-3g defaults,locale=en_US.utf8 0 0

Add the above line to the end of that file. (Here sda2 is the ntfs partition, getting from fdisk -l )

Restart ubuntu and you can see the ntfs filesystem mounted on /media/windowsC

One day , while i am viewing my website, i got the error message is that, your mysql table has been corrupted. I wonder what happened to my database. I used phpmyadmin for its repair. But no use. Gone is gone !!!

All this happened only because of the lack perfect backup of mysql database. You can backup your mysql database in some simple step. I think you know the mysql command mysqldump. This will create an sql file for your database. See example,

mysqldump -u<your_db_username> -p<your_db_password> databasename > /path/to/backup.sql

If you want to save this sql backup in a remote server, use scp command

scp /path/to/bakup.sql root@yourserverip:/path/to/remote/server

This will ask for your current useraccount’s password and remote server password. Thus your backup file is saved to a remote server

If you want to take backup periodically , add this command to your cron and execute as you wish , daily, weekly or monthly .

Go and enjoy programming , dont worry about backup, its already taken

Trac is an issue tracking system with wiki support. It also provide interface to subversion. It can be used as Web Subversion.

Installation of trac >

use
apt-get install trac
or
yum install trac

depends on your operating system.

user this link for more installation help :http://trac.edgewall.org/wiki/TracDownload

After the installation, you have to setup the trac Environment Directory. For that create a folder any where in you system.

(mkdir myenv) and give full permission to that environment (chmod -R 777 myenv)

To make this directory as your trac environment , use the following command.

trac-admin /path/to/myenv initenv

It will ask for name of your project, mysql connection string, type of subverstion, repository path, and template of your trac.

1) Provide a name for your project

2) If you are not using mysql, the trac by default use Sqlite database . Just enter the option for blank

3) Enter type of subversion there. Just type ‘svn’ if you are using svn subversion.

4) Enter the path to your repository

5) Leave the template option blank. Lets change that later.

Now your trac environment is ready.

You can change the above configuration form the trac.ini file in the trac environment folder.

Some useful links :

http://trac.edgewall.org/wiki/TracAdmin
http://trac.edgewall.org/wiki/TracIni
http://trac.edgewall.org/wiki/TracEnvironment

Now lets start trac as standalone . (There are two more option to start trac)

http://trac.edgewall.org/wiki/TracStandalone

For that you can use tracd

eg: tracd -p 8080 /path/to/projectenv

here -p is your portnumber.

If you want to set your hostname also use,

tracd –hostname=localhost -p 8080 /path/to/project

For starting tracd as a daemon , use -d option
eg: tracd -d -p 8080 /path/to/projectenv

if you want to add more than one project through a single port , use

tracd -p 8080 /path/to/project1 /path/to/project2

another way to start multiple project trac is :

tracd -p 8080 -e /path/to/parentenv

Setting trac Authentication >>>

tracd -p 8080 –auth /path/to/project1env,/path/to/users.htdigest,mycompany.com /path/to/project1env

where users.htdigest is the password digest file of user accounts, and mycompany.com is the realm which set when creating the password digest.

How can i create the users.htdigest file.

this link will help you for that : http://httpd.apache.org/docs/2.0/programs/htdigest.html

the command for creating user htdigest file is :

htdigest [ -c ] passwdfile realm username

where -c option is for creating new file, by overwriting old one (if exists)

for adding more users avoid the -c part

Setting Permission >>

trac-admin /path/to/projenv permission add bob TRAC_ADMIN

For giving permission to users you can use this link:

http://trac.edgewall.org/wiki/TracPermissions
http://lists.nexusformat.org/pipermail/nexus-developers/2006/000696.html

Mail me for any queris to: admin@sajithmr.com

Thanks and Regards
Sajith.M.R

Setup Subversion (svn) >>

Depends on your linux version use package managers
apt-get install subversion
or
yum install subversion

How can i create respository ?

Create a folder which you want to make as repository.

svnadmin create /path/to/folder

If you check the folder after this comment, you can see some files there viz
conf dav db format hooks locks README.txt

Your Repository is okay now. For more http://subversion.tigris.org/project_packages.html

How can i set a port and host for checkin/checkout and commit the project , simply add contents to respository ?

You can use svnserve for this purpose.

svnserve -d -r /path/to/repository

This will listen the default port 3690. You can access this repository via svn://hostname.com

You can use options –listen-port and –listen-host for changing the port and host .

Then the svn checkout action will be like this : svn checkout svn://host.example.com/project1

How can I set Authentication to this repository ??

You can see a conf directory in your repository folder. There you can see three files
authz, passwd, svnserve.conf

edit svnserve.conf

Uncomment the following for setting access control:

anon-access = read // This means anybody can read the repository (checkout)
auth-access = write // Only authorized member can write / update repository

anon-access = none // This means only authorized member can read the repository

How can i set Access Control ?

uncomment the following line

password-db = passwd

where userfile is the file which contains username and passwords for the repository

eg of passwd :

[users]
sajith = pass123
jilmon = mypassword
vivian = passworrd
balu = testpass

Then come to the last part of configuration file. It is

authz-db = authz (svnserve.conf)

lets see what is inside authz

eg:

folder wise permission

[/]
sajith = rw
vivian = r
jilmon = r
balu = rw

(above permission is for whole the repository)
You can use * for all

eg:
[/]
* = rw

For more : http://svnbook.red-bean.com/en/1.0/ch06s03.html

A sample svn client : http://tortoisesvn.tigris.org/

Operating system level programming has a different taste than any other
programming. It is very simple to understand the operating systems layers if
you do os programming in linux. You can start that with system calls such as
fork, pipe, memget, kill etc .

For example, you know pipe. In linux command prompt ‘|’
is using for pipe. For example ls is the command for list the directory …
ls | more means ?? It means give the output of ls command to more command. “more”
command’s input will be the output of “ls” command. Here the
output and input are piped. Standard input and output are changed.
(“more” command is using for showing page by page data)

Example Code:

Click read more for sample code

#include 
#include 
#include 
#include 

int main(){

pid_t pid;
int rv;
int commpipe[2]; /* This holds the fd for the input & output of the pipe
*/

/* Setup communication pipeline first */
if(pipe(commpipe)){
fprintf(stderr,"Pipe error!\n");
exit(1);
}

/* Attempt to fork and check for errors */
if( (pid=fork()) == -1){
fprintf(stderr,"Fork error. Exiting.\n"); /* something went wrong
*/
exit(1);
}

if(pid){
/* A positive (non-negative) PID indicates the parent process */
dup2(commpipe[1],1); /* Replace stdout with out side of the pipe */
close(commpipe[0]); /* Close unused side of pipe (in side) */
setvbuf(stdout,(char*)NULL,_IONBF,0); /* Set non-buffered output on stdout */
sleep(2);
printf("Hello\n");
sleep(2);
printf("Goodbye\n");
sleep(2);
printf("exit\n");
wait(&rv); /* Wait for child process to end */
fprintf(stderr,"Child exited with a %d value\n",rv);
}
else{
/* A zero PID indicates that this is the child process */
//dup2(commpipe[0],0); /* Replace stdin with the in side of the pipe */
close(commpipe[1]); /* Close unused side of pipe (out side) */
/* Replace the child fork with a new process */
if(execl("child","child",NULL) == -1){
fprintf(stderr,"execl Error!");
exit(1);
}
}
return 0;
}