Unix time is defined as the number of seconds that have elapsed since midnight Coordinated Universal Time (UTC), 1 January 1970,not counting leap seconds. It is used widely in Unix-like and many other operating systems and file formats. It is neither a linear representation of time nor a true representation of UTC. Unix time may be checked on some Unix systems by typing date +%s on the command line.Sometimes it's a bit difficult to compare times stored in different applications or systems with different formats. For example, if we want to compare a DATE in Oracle with a date string in Unix, we...

Microsoft announced on its official blog the price to upgrade to Windows 8 Pro would increase from $40 to $200 starting from February 1.According to the data released by Microsoft at the CES conference, since on sales in October last year, 60 million copies of Windows 8 licenses are sold, but they did not disclose the specific amount of activation. In order to attract users to upgrade to Windows 8, Microsoft set the upgrade fee to $39.99.Microsoft said that the price would change as follows from February 1:Windows 8 Pro upgrade price of $199.99Windows 8 upgrade version price of $119.99Windows ...

A small development team in the intranet will frequently transfer codes, share files. Here are some command we use frequently to release some of our work. They are not applicable to Windows users.1. Output program execution output through GTalk.Sometimes we may need to send the program execution result and log to teammates for debugging using IM. These outputs are very troublesome to copy and send while in command line mode. So we could have a program called gpipe.py which can put GTalk as a pipe after one program. For example:make 2>&1 | gpipe tinyfoolWith this line, The GTalk client o...

It's very common that we need to transfer files between two different hosts such as backups. It is also an very simple task, we can use scp or rsync to complete the task well. But what if the file is very big, it may take some time to transfer it. How can we transfer a big file with high speed? Here we propose one solution.Copy fileIf we copy one uncompressed file, then we should follow below steps:Compress dataSend it to another hostUncompress the dataVerify the data integrityThis will be very efficient and it also saves bandwidth.With ZIP+SCPWe can combine ZIP and SCP to achieve this.gzip -c...

In PC era, Microsoft is the world's largest software service provider, its revenue  is mainly from selling operating systems and other software services.With the advent of the era of mobile Internet, the free software service concept has been widely accepted, Microsoft has been forced to explore new business models.According to ZDNet, Microsoft's next-generation OS Windows Blue is expected to be released in mid of 2013. The biggest difference between the new version of the OS and the previous version is not the changes in the features, but he strategy of low-price or even free. Microsoft ...

On *nix, some processes may not be able to start up, software runs very slowly suddenly and software's "Segment Fault" are some issues faced by many *nix users. Here we show you how to use truss to trace why Vim becomes slow suddenly.Operating system : FreeBSD-5.2.1-releasvim version is 6.2.154, after typing vim on command line, sometimes we need to wait for a few minutes to get into the edit interface and there is no error output. After carefully checking .vimrc and all vim settings, there are no error configuration. Also there are no similar solutions online. Do we need to hack the source co...

Shell is also called command line interface, it is the interface between *nix users and computer. Shell is a program which provides service to access OS kernel services.This article is to introduce some not so well known but useful and interesting knowledge about shell.Wikishell was born almost at the same time as Unix. The first UNIX shell was written by Ken Thompson in 1971 and its name is Thompson sh. It's older than Linux kernel.The default Shell in most *nix and MacOS is bash, bash was created by Brian Fox in 1987, the full name is Bourne Again shell(bash).There are other shells except ba...

ext3 is a journaled file system that is commonly used by the Linux kernel. It is the default file system for many popular Linux distributions, including Debian. Stephen Tweedie. On June 28, 2006, Theodore Ts'o, the principal developer of ext3, announced an enhanced version, called ext4. Today, we will show how to convert ext3 to ext4 format on CentOS.System environment:Release version : CentOS release 5.4(Final)Kernel:  Linux localhost.localdomain 2.6.18-164.el5 #1 SMP Thu Sep 3 03:28:30 EDT 2009 x86_64 x86_64 x86_64 GNU/LinuxAssume the pa...