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HowTo: Linux / UNIX Unset TMOUT ( AutoLogOut )

I've set the the TMOUT in the ~/.profile of the user account as well as in /etc/profile file on my UNIX or Linux servers. How do I unset the TMOUT variable? How to unset TMOUT temporarily under UNIX like operating systems?
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Bash Shell Script Function Examples

How do I create a shell script function using Bash under UNIX / Linux operating systems?
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How do I add a new path to $PATH variable under Linux and UNIX like operating system? What is my path, and how do I set or modify it using csh/tcsh or bash/ksh/sh shell?
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I just need a help to show me how to setup java path on Linux. How can I set JAVA_HOME and PATH variables for every user under my Linux system?
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OpenBSD Install MySQL Server

Q. How do I install and run MySQL version 5 database Server under OpenBSD UNIX operating system?

A. OpenBSD has pkg_add command. It is used to install packages created with the pkg_create command. Selected packages containing pre-compiled applications from the /usr/ports tree can be found on the OpenBSD FTP site or on the official OpenBSD CD. pkg_add is the easiest way to install new packages, to replace existing packages with other flavors (option -r) or to update packages to newer versions option -u).

Install MySQL Database Server on OpenBSD

First setup installation mirror i.e. PKG_PATH using export command:
$ export PKG_PATH=ftp://mirror.planetunix.net/pub/OpenBSD/4.1/packages/`machine -a`/
Next install MySQL server, using pkg_add command, enter:
$ sudo pkg_add -i -v mysql-server
OR
# pkg_add -i -v mysql-server
Output:

parsing mysql-server-5.0.33
Dependencies for mysql-server-5.0.33 resolve to: p5-DBD-mysql-3.0008, mysql-client-5.0.33 (todo: mysql-client-5.0.33,p5-DBD-mysql-3.0008)
mysql-server-5.0.33:parsing mysql-client-5.0.33
mysql-server-5.0.33:mysql-client-5.0.33: complete
mysql-server-5.0.33:parsing p5-DBD-mysql-3.0008
Dependencies for p5-DBD-mysql-3.0008 resolve to: mysql-client-5.0.33, p5-DBI-1.53 (todo: p5-DBI-1.53)
mysql-server-5.0.33:parsing p5-DBI-1.53
Dependencies for p5-DBI-1.53 resolve to: p5-PlRPC-0.2018p0 (todo: p5-PlRPC-0.2018p0)
mysql-server-5.0.33:parsing p5-PlRPC-0.2018p0
Dependencies for p5-PlRPC-0.2018p0 resolve to: p5-Net-Daemon-0.39 (todo: p5-Net-Daemon-0.39)
mysql-server-5.0.33:parsing p5-Net-Daemon-0.39
mysql-server-5.0.33:p5-Net-Daemon-0.39: complete
mysql-server-5.0.33:p5-PlRPC-0.2018p0: complete
mysql-server-5.0.33:p5-DBI-1.53: complete
mysql-server-5.0.33:p5-DBD-mysql-3.0008: complete
adding group _mysql
adding user _mysql
installed /etc/my.cnf from /usr/local/share/mysql/my-medium.cnf****************************************************************************************************     | 97%
mysql-server-5.0.33: complete
--- mysql-server-5.0.33 -------------------
The mysql-server package doesn't initialize a default database.
Please run /usr/local/bin/mysql_install_db to create one.

Install default MySQL database

By default MySQL database is not initialized, enter the following command to create a default database:
# /usr/local/bin/mysql_install_db
Output:

Installing all prepared tables
Fill help tables
PLEASE REMEMBER TO SET A PASSWORD FOR THE MySQL root USER !
To do so, start the server, then issue the following commands:
/usr/local/bin/mysqladmin -u root password 'new-password'
/usr/local/bin/mysqladmin -u root -h openbsd.nixcraft.in password 'new-password'
See the manual for more instructions.

Start MySQL server

Now you have MySQL server installed. Start the server daemon, enter:
# /usr/local/bin/mysqld_safe &
Output:

[1] 7750
Starting mysqld daemon with databases from /var/mysql

Connect to MySQL server

Run mysql command to test if everything is working fine, enter:
# mysql
Output:

Welcome to the MySQL monitor.  Commands end with ; or \g.
Your MySQL connection id is 1
Server version: 5.0.33-log OpenBSD port: mysql-server-5.0.33
Type 'help;' or '\h' for help. Type '\c' to clear the buffer.
mysql> quit
Bye

Set root password

You must set a password for the MySQL root user, enter:
# /usr/local/bin/mysqladmin -u root password 'YOUR-Secret-Password'
To access the MySQL server with password, enter:
$ mysql -u root -p

Create MySQL startup and stop script

Finally, you need a script to start and stop MySQL Server. In order to start MySQL server at boot time, enter following command in /etc/rc.conf.local file:
# vi /etc/rc.conf.local
Append following line:
mysql=YES
Save and close the file. Now you need to edit /etc/rc.local file. It is use to specify site-specific startup actions, daemons, and other things which can be done AFTER your system goes into securemode:
# vi /etc/rc.local
Find out line which read as follows:
# Add your local startup actions here.
Append following code:

# MySQL startup
if [ X"${mysql}" == X"YES" -a -x /usr/local/bin/mysqld_safe ]; then
   echo -n " mysqld "
   /usr/local/bin/mysqld_safe --user=_mysql &
fi

Save and close the file.

How do I stop MySQL server under OpenBSD?

Use mysqladmin command:
# mysqladmin -u root -p shutdown

Display or print UNIX / Linux path ~ $PATH variable

Q. How do I print current path settings under BASH shell? I’m using Debian Linux.

A. In UNIX / Linux file systems, the human-readable address of a resource is defined by PATH. On Unix / Linux like operating systems, (as well as on DOS / Windows and its descendants), PATH is an environment variable listing a set of paths to directories where executables may be found.

Display current PATH

Use echo command:
$ echo $PATH
Output:

/usr/local/sbin:/usr/local/bin:/usr/sbin:/usr/bin:/sbin:/bin:/usr/bin/X11:/usr/games

Modify current PATH

Use export command to add /opt/games to PATH, enter:
export PATH=$PATH:/opt/games

To format your PATH variable for easy viewing, add following code to your bash startup file (such as ~/.bashrc or ~/.bash_profile) :

function path(){
    old=$IFS
    IFS=:
    printf "%s\n" $PATH
    IFS=$old
}

(Function credit: usenet archive)

Now just run path:
$ path
Output:

/usr/local/sbin
/usr/local/bin
/usr/sbin
/usr/bin
/sbin
/bin
/usr/bin/X11
/usr/games

Q. I find vi hard to use. How do I change my default text editor from vim / vi to Pico under Debian Linux?

A. To use and change an editor to edit your text message, set the variable EDITOR to the pathname of the vi / vim binary file. You need to use export or set command for the same purpose.

Many Linux / UNIX command read shell EDITOR environment variable to determine which editor to use for editing a text file.

Set default text editor to pico

Type the command as follows:
$ which pico
Output:

/usr/bin/pico

Now setup a new text editor:
export EDITOR=/usr/bin/pico
OR
export EDITOR=pico

Add above line to ~/.bashrc file:
$ vi ~/.bashrc
Append text as follows:
export EDITOR=pico
Close and save the file. There is no no need to reboot system.

Also you can add alias if you want:
alias vi=/usr/bin/pico