Introduction Removing empty lines in a text file from the Unix shell is quite easy. There are a couple of ways to do that. Let us explore a few… Remove empty lines using sed command The stream editor (sed) can be used to filter and transform text. Removing empty lines using sed can be done
Introduction To check service port numbers on a Unix based operating system, you may use one of the following methods… netstat command netstat command is used to display network related data. It is available on most Unix flavors including MacOS. The syntax may vary so it is recommended to check the manual (ex. man netstat
Introduction Assume we have a directory structure (ex. product source code) and we want to share it with someone. To do that on Unix, we can tar the directory structure (convert to a single file archive) then compress the file. If we do not pay due attention, original file and directory paths can be retained
Introduction Before we start, I recommend that you read this post first. It talks about concurrency in operating systems and clarifies the main difference between multitasking, multithreading, multiprogramming and multiprocessing. If you are done, let us proceed and define some relevant terms so that things are put into perspective. In this article, I am targeting
System Call In order to better understand the difference between different call types, let us set some context for discussion. We are referring here to modern operating system (OS) design concepts. So, what are the main goals of having an OS in the first place ? Well, the OS achieves two primary goals for users.
Introduction A YouTube video can be either public (anyone can watch), private (only the owner can watch) or unlisted (anyone with a link can watch). I like the third option because I can share the links with whoever I want and at the same time my videos do not show up in search results. If
The rsync command can be used to sync files between Unix machines or between a Unix machine and Mac computer. Here is the syntax What if you want to copy files from a Unix machine to a local Windows machine. Here is how: Install http://sourceforge.net/projects/grsync-win on the windows Machine then launch it and fill as
This is my cheat sheet for SCCS the UNIX source code control system SCCS Commands To edit a file: sccs edit To unedit a file: sccs unedit To check in a file: sccs delget To list all the files that are checked out: sccs info To see the history of a file: sccs prt To
Problem You have a log file on UNIX operating system. Each line in the log file contains an IP address in the 10th column where columns (or fields) are separated by a space. How can you print the unique IP addresses in the log file using UNIX shell Solution This is the same problem as
