Linux

How to configure libstdc++ with GCC 4.8?

You need to tell your dynamic linker (it’s executed when you run your program) where to find the library. Set LD_LIBRARY_PATH to the path of the library (probably somewhere under /app/gcc/4.8.0/lib or something).

Use find /app/gcc/4.8.0 -name “libstdc++.so.6”. Add the directory to your LD_LIBRARY_PATH. e.g with the path I mentioned:

export LD_LIBRARY_PATH=$LD_LIBRARY_PATH:/app/gcc/4.8.0/lib (if you’re using a bourne-like shell which the default on Linux).

Then try to run your program.

Voila!!

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Linux

Setup Pure-FTPd Daemon in Linux

Install Pure-FTPd
In a Linux shell run the following:
Ubuntu –
apt-get install pure-ftpd-common pure-ftpd

Red Hat, Centos-
yum install pure-ftpd-common pure-ftpd

Now we need to create a new system group for pureftpd:

groupadd ftpgroup

Now we add a user for the group and give that user no permission to a home directory or a shell:

useradd -g ftpgroup -d /dev/null -s /etc ftpuser

Create a new user
Lets create our first FTP user. In this example our user will be “justin”:

pure-pw useradd justin -u ftpuser -g ftpgroup -d /home/pubftp/justin -N 10

In the above command we gave him a limit of 10 MB disk space with the option “-N 10”. Now you have to enter justin’s new password twice.
By default your users will be saved in /etc/pure-ftpd/pureftpd.passwd, but first we have to update the pureftpd Database:

pure-pw mkdb

The “Database” here is simply a binary file but it is ordered and has an index for quick access.
User Information
To get some user details enter the following to get a complete list of all pureftpd users:

pure-pw list

If you want to show information about a specific user:

pure-pw show justin

This will show you detailed information about the user “justin”.
You will notice that the line “Directory: /home/pubftp/justin/./” has a trailing ./ but you shouldn’t worry as this is simply the chroot for the user, which means he can’t go “above” his directory.
Resetting a password
If you forget the password for a user, you can reset it as follows:

pure-pw passwd justin

After a password reset update your database:

pure-pw mkdb

Starting the FTP Server
To test the server let’s start it:

/usr/sbin/pure-ftpd -S 127.0.0.1,21 -c 30 -C 1 -l puredb:/etc/pureftpd.pdb -x -E -j -R

The shell will open up a new pure-ftpd session and you should be able to connect to your FTP server. Use an FTP client to test whether or not you are able to login with your user details you created.
Once you are happy close the session off:

ctrl z

Configuring Pure-FTPd
Right so by now you have created a user and been able to connect to your FTP server. We now want to setup a few things so that we can run Pure-FTPd as a daemon.
First you need to set Pure-FTPd as a standalone server:

vim /etc/default/pure-ftpd-common

Replace this:

STANDALONE_OR_INETD=inetd

With this:

STANDALONE_OR_INETD=standalone

Now we want to ensure that the standalone server checks our usernames and passwords against the pureftpd database file:

cd /etc/pure-ftpd/conf
vim PureDB

Add the following to that file (if it doesn’t exist):

/etc/pure-ftpd/pureftpd.pdb

Now we need to create a symbolic link to the PureDB file:

cd /etc/pure-ftpd/auth
ln -s /etc/pure-ftpd/conf/PureDB 50pure
ls -ls

You should now see a new file “50pure” linking to ../conf/PureDB.
Restart Pure-FTPd:

/etc/init.d/pure-ftpd restart

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Linux

Linux Open Port 80 (HTTP Web Server Port)

Login as root user and type:

# vi /etc/sysconfig/iptables
Append rule as follows:
-A RH-Firewall-1-INPUT -m state --state NEW -m tcp -p tcp --dport 80 -j ACCEPT
Save and close the file. Restart iptables:
# /etc/init.d/iptables restart

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