All posts by Mehrad

Install wget on Mac OS X

When you are a Linux user, you are so familiar to wget command. In simple words, it is a command to download file from a given URL and port. Most Linux users and some windows users are familiar to this handy command download tool and on most Linux distributions it is pre-installed, but on Max OSX it is not installed and Apple does not offer it in AppStore, so the suer should install it manually, which is so straightforward, fast and easy.

In this tutorial I want to describe how to install wget on Mac OS X.

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Limit application CPU usage in Mac

This problem occurred to me when I was contributing with Folding@Home project of Stanford University. Their application (also known as fahclient) was using all my computers CPU and the temperature of my Mac’s graphic card was around 89 degrees centigrade. So I tried to limit the CPU usage of this application within it’s preferences menu, but it was not working at all, so I searched Internet and I found that this is a common problem an the solution was not that well-known ! So in this post I’m going to describe how to limit application CPU usage in Mac OSx. In this tutorial I’m going to use cputhrottle which is a small OS X command-line utility designed to limit the CPU usage of a process to which it attaches.

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Install KeePass on Linux

Most professionals use multiple highly complex passwords for every purpose  so the only problem usually occurs is saving password somewhere safe and accessible. There are few good choices for storing passwords, some are online such as LastPass and some are off-line in which the passwords will be encrypted and stored in files. The best password manager application I know and ever tested is KeePass.

The main reason why KeePass 2.x  is not so popular in Linux base operating system community is because this software does not have Linux or Mac version, but it is easy to run it on Linux. Mind that there are some native Linux applications such as KeePassX that can handle .kdb files which is used for KeePass 1.x but the KeePass2.x uses another file format which is .kdbx

In this tutorial, I’m going to write the best way to install KeePass on Linux. Also you can find how to install KeePass on Mac OSX in this website.

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Edit Grub timeout setting

When you have multiple operating system on your computer, you should use an boot loader (OS-Selecctor) to switch between your different OS while booting up your system. There are several different boot loaders available now a days, but the most common one in Linux world perhaps is GRUB.

While using a boot loader (in this case, GRUB), you may want to change the default amount of timout before the boot loader choose the default selection. So i’m going to tutor how to change this setting.

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Working with .rar files in Linux

Usually I don’t face .rar files and if I did, there were many online websites that would handle those files for me. But finally i got to this point that I need to take care of these files my self because of security issues and sometimes the size of files (sometimes more than 50MB per file). so I dived into finding the best solution.

There are many Linux based application out there that you can try, some will provide you GUI and some has TUI and some of theme have both. In this article i’m going to introduce the most suitable application I found:

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Find and replace a string in entire mysql database

Most of the time when you want to copy a website for another use or even when you are changing your URL, you face this problem that you should search for the old URL among all records of database and then replace it with new one.

There are many ways and many scripts designed for this issue and each has a disadvantage.

I faced this problem and tested few of these ways but they are mostly causing more problem, specially when you have too many tables and too many columns. So I found the following way and it worked like charm:

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Error: “Error getting a Request Token: Bad Request”

Q: Why do I receive this error “Error getting a Request Token: Bad Request” when I try to add Online Account to my Linux?


A: This Error pops up when your computer time is not acceptable by Google server. This issue can be solved by setting your computers time and region.

In below you can see the link of RedHat Bugzilla post about such a problem.:

Setup MySQL Server on CentOS or RHEL

One of the most common databases is MySQL and the best medium for this database type is Linux. To setup this database, you should follow the following steps in order to install it easily and securely.

These steps contains:

1. Installing MySQL server daemon
2. Installing MySQL module for PHP
3. Starting MySQL daemon
4. Follow security wizard
5. Set MySQL daemon to run at boot

These 5 steps are the most basic things you should do before using your server for business.

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