The grep command is a search command built into a variety of Unix based operating systems. This command line utility, whose name stems from the original Unix term which means “search globally for lines matching the regular expression, and print them,” can be accessed using the command line or terminal from anywhere in the Unix operating system. When given a particular list of files to search through, the grep command becomes especially useful, as it can search through any amount of text to find exactly what you are looking for. Read More

The total number of Unix commands is immense. No normal user or system administrator would ever need to know them all. The Unix commands available to you will vary based upon several factors: The version of Unix you are using (FreeBSD, Linux, Solaris, AIX, HP-UX, OpenBSD, etc…) The Unix shell you are using (sh, csh, tcsh, ksh, bash, etc…) The packages installed on the system and the way the system is configured Your access level on the system This list of basic Unix commands will get you started using and Read More

Unix Shell Scripting Tutorials This Unix shell scripting tutorial provides samples and instructional materials that are easy to understand and useful for Unix shell scripting. It also offers illustrated samples that will helps users explore different avenues of Unix shell scripting.   Bourne Shell Programming Tutorial Learn how to use the Unix shell with this comprehensive Bourne Shell Programming/Scripting Tutorial. It contains many example codes with explanations. Heiner’s SHELLdorado This Unix shell scripting resource contains numerous coding examples. It has a section on “Good Coding” as well as a long Read More

For those computer users that have both Unix and Window’s operating systems, you should know that you can easily copy your Unix files from a Unix computer and transfer them to a Windows computer. Using Client for NFS, you can transfer any existing Unix files from your Unix server to a Windows based server. It should also be noted that once you send the file system or folder from the Unix server to the Window’s server, you can then move either whole folder trees in just one single step. Transferring Read More

Unix users write, edit, list, and remove cron jobs using the `crontab` command. `crontab -e` takes users into their default editor to edit their crontab entries. `crontab -l` lists their crontab. `crontab -r` removes their crontab. crontab Security If the cron.allow file exists, then the user must be listed in that file in order to be allowed to use the `crontab` command. If the cron.allow file does not exist but the cron.deny file does, then the user must not be listed in the cron.deny file in order to use this Read More

Solaris makes it unreasonably difficult to change an installed server’s hostname. To change the hostname on a Solaris system, edit all of these files: /etc/hosts /etc/nodename /etc/hostname.* /etc/inet/ipnodes When file editing is complete, reboot the server to test the changes and ensure that they operate correctly. Note that changing the hostname only changes the name by which the machine refers to itself. This does not change the DNS name or names of the host.

Unix provides hundreds of useful commands for all sorts of purposes, but it is sometimes difficult to find the specific command you are looking for. To assist you with this task, most versions of Unix provide the `man -k` command. The `man -k` command searches the online manual pages to help you find the Unix command for which you are looking. For example, suppose you forgot the command to backup your Unix system. You might search for the word backup: $ man -k backup dump(8), rdump(8) – file system backup Read More

The Unix sort command is a command for the Unix family of operating systems. It is designed to sort whatever information you give it. The command can be used for a variety of purposes, but it is most frequently employed when there are a number of different files which need to be ordered in some particular way. When the command is executed, the files which were sorted will be printed to the screen in an easy to view box with the files sorted per your instructions. Using the Unix sort Read More

Tar refers to a tape archiving file format and the program that creates them. Tar stands for tape archive. It combines multiple files together so that they can be used for programs, applications, and critical system files. While Tar does not directly install files to a user’s hard drive, it is responsible for compiling the files together so that they can be transferred from one computer to another while preserving important information such as directory structures, user permissions, and dates. Tar can be used on its own to archive and/or Read More

UNIX is one of the most important operating systems ever developed. What made Unix stand out in the crowd of countless other operating systems is that it was a competent operating system that was extremely affordable and worked on low cost hardware. Economics definitely played a large part in UNIX’s popularity and today it is still known as a low cost solution to running personal computers, network servers or large commercial servers. UNIX was originally created in 1969 at AT&T Bell Labs by Ken Thompson, Douglas Ritchie and Douglas Mcllroy. Read More