Crea sito

Archivio per la categoria Linux_Note

How to get information about process memory usage

Each process running on a machine uses some memory, allocating memory on a heap or in the stack. In linux system there is a way to know how to get information about process memory usage, so that you can control how much memory a process is using and also check if there is any memory […]

GRUB, a missing partition

A little introduction: When in your system you have different operating system you need something that allows you to chose which operating system to use every time you boot your machine. This “thing” is called a boot loader.  The greatest loader for booting Linux and practically any other OS open source or otherwise is probably […]

How to convert .chm to .pdf files

Here it is a simple guide that shows how to convert .chm to .pdf files. First of all, a little introduction: CHM (Microsoft Compiled HTML Help) is a Microsoft proprietary online help format, that consists of a collection of HTML pages and an index and that is often used for software documentation PDF (Portable Document […]

How to count the files inside a directory and the subdirectories

Count the files Here there is the problem: given a directory, we need to get the number of the files (not directory) inside this directory (and the subdirectory). Plus, we need to count the numbers of the files for each subdirectory, in the same way. For example, if we have a directory like this: directory1: […]

How to know which version of Ubuntu you are running

There are a lot of versions of Ubuntu spread all over the years, but which one are you running? It’s easy, the information that you need is stored into /etc/issue. So, just type:            cat /etc/issue and you’ll see which version of Ubuntu you’re running. For example, in my case, that’s […]

How to convert .nrg to .iso

How to convert .nrg to .iso : If you want to convert .nrg file to .iso file there is a simple tool that you can use: nrg2iso. This tool extract SO9660 data from Nero “.nrg” CD-ROM image files. Here there are the steps that you need to follow to install and use nrg2iso: Installation (with […]

How to nat a PC with an other PC

Here is the situation: you have 2 (or more) PCs with Linux system. One PC has at least 2 network interface and with one on them it is connected on Internet. The second PC instead has no access to the internet. If you want that also the second PC gets a connection, you can use […]

How to limit the CPU usage of a process: cpulimit

How to limit the CPU usage of a certain process of a Unix System: cpulimit. cpulimit is a program that attempts to limit the cpu usage of a process. This limit is a percentage of real cpu usage and not a cpu time. cpulimit is also able to adapt itself to the overall system load, dynamically and quickly. How […]


How to reduce PDF file size

If you want to reduce PDF file size using command line on Linux System you can use ghostscript. Ghostscript is used for PostScript/PDF preview and printing. First of all, you have to install the gs command: sudo apt-get install ghostscript After that, you can simply execute the following command to reduce the size of a PDF […]

Tags: , , ,

How to extract audio (mp3) from a video (flv or mp4)

If you have a mp4 or flv video (for example a video that you downloaded from youtube) and you want to get only the audio (mp3), here there is a simple solution. Before you start, you have to install on your Linux system ffmpeg and lame Here there is the command list: ffmpeg -i video.mp4 […]