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 …
The Unix find command, as the name implies, is a command that you can enter into the command line, or terminal, of a Unix operating system, allowing you to process any given set of files or directories. It is a highly useful command that you can take advantage of on Unix based operating system, making …
umask is a Unix shell built-in command that automatically sets file permissions on newly created files. The umask command can be confusing to use because it does work as a mask. In other words, the user sets the permissions that he/she does not want in the umask. To calculate permissions that will result from specific …
Bootable distributions of the Linux operating system are becoming very popular for use in securing networks, testing network security, and conducting forensics after suspected intrusions. Local Area Security Linux Local Area Security Linux is a ‘Live CD’ distribution with a small footprint. Containing over 200 information security and administration related tools, as well as a …
The idea of a restricted shell first arose in the Unix operating system in order to prevent the end-user from doing as many operations as a normal shell allows. A restricted shell lets the administrator control the end-user’s computing environment by only permitting explicitly used commands to be used. The Linux restricted shell (rssh) is …
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 …
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 …
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 …
List Logged In Unix Users Unix has many commands to list users who are logged in. These commands include ‘w,’ ‘who,’ and ‘users:’ $ w 9:51PM up 99 days, 5:39, 2 users, load averages: 0.83, 0.90, 0.90 USER TTY FROM LOGIN@ IDLE WHAT will p0 c-66-164-235-73. 8:11AM – w spencer p3 c-66-164-235-73. 8:26PM 1:24 pine …
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 …