A restricted shell is a Unix shell that has been modified to allow the Unix shell user to do fewer things than a normal shell would allow him to do. It may allow the user to run only certain programs. It may stop the user from changing directories. Many sites run their own restricted shells …
One of the best methods to capture a Unix terminal session is to use the `script` command. In this example we start a script session, run a couple of commands, and then use the `exit` command to stop capturing the terminal session: $ script Script started, output file is typescript $ pwd /home/will $ ps …
A computer process is a computer program that is executing and has a unique process identification or PID. On the Unix Operating System (OS), a process may be running in the background, foreground, or be in a suspended state. On Unix, the OS shell will not return the prompt to the end-user until the current …
One way that a small business that requires a file server can save thousands of dollars per year is to set up a Linux file server. Linux is an open source software platform that, in many ways, is just as good as or better than other types of platforms including Microsoft and Sun. Small businesses …
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 …
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 …
Linux is a free, open source operating system that competes with the Windows Operating Systems and Mac OS X. Linux is widely used on a number of devices such as servers, desktops, laptops, smartphones, PDAs, game consoles, tablet computers, supercomputers, and mainframes. Linux controls only about 4.9% of the market share of desktop computers while …
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 …
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 …
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 …