ops102_1_2.pdf

Introduction OPS102 Week 1 Class 2 Tiayyba Riaz/Chris Tyler May 5, 2024 Seneca Polytechnic Outline Recap From Last Class A Bit of History cont’d Command Line and Commands Open Source and Proprietary Software OPS102 W1C2 - Introduction Part 2 1/21 Recap From Last...

Introduction OPS102 Week 1 Class 2 Tiayyba Riaz/Chris Tyler May 5, 2024 Seneca Polytechnic Outline Recap From Last Class A Bit of History cont’d Command Line and Commands Open Source and Proprietary Software OPS102 W1C2 - Introduction Part 2 1/21 Recap From Last Class Recap From Last Class Course introduction and overview Operating system basics, components, and interfaces A bit of history OPS102 W1C2 - Introduction Part 2 2/21 A Bit of History cont’d A Bit of History cont’d Recall we talked a little bit about the history of UNIX And PC-DOS / MS-DOS And PC-DOS / MS-DOS 2.0 added hierarchical filesystems With backslash as the pathname separator OPS102 W1C2 - Introduction Part 2 3/21 Operating Systems get GUIs GUIs were added to Unix systems starting in 1984 with the introduction of the X Window System from Project Athena at MIT. DOS received multi-tasking abilities and a GUI with the introduction of Windows 1.0 in 1985. Windows NT 3.1, released in 1993, was a new 32-bit operating system that combined features from DOS/Windows and a jointly-developed Microsoft-IBM operating system named OS/2. Not based on MS-DOS, but compatible with MS-DOS All modern versions of Windows are derived from Windows NT. Other early GUI systems include Xerox Star (1981), Apollo DN100 (1981), Sun Sun-1 (1982), Apple Lisa (1983), Apple Macintosh (1984) OPS102 W1C2 - Introduction Part 2 4/21 Unix Evolves from Product to Standard Unix was originally a proprietary product of Bell Labs / AT&T. Eventually, it became a family of related operating systems customized by various vendors and sold under many different names (XENIX, AIX, Ultrix, HP/UX, and more). Various standard bodies, including the IEEE, The Open Group, and ISO created standards to define what a “Unix-like” operating system should contain and how it should operate. Ultimately, Unix became a trademark rather than a product, and any operating system that was tested and proven to conform to the Unix standards was granted permission to use the Unix trademark. OPS102 W1C2 - Introduction Part 2 5/21 The Post-Unix World While originally considered valuable, the importance of the Unix trademark is no longer as significant as it once was. Many contemporary operating systems are regarded as Unix-like, although few have gone through official conformance testing. Apple’s MacOS is officially a Unix system Linux is not officially a Unix system OPS102 W1C2 - Introduction Part 2 6/21 Unix-Like Operating Systems Linux Mac OS and iOS Though generally only “under the covers” FreeBSD and OpenBSD and NetBSD And many others! OPS102 W1C2 - Introduction Part 2 7/21 Operating Systems In this Course We’re going to focus on two operating systems: Windows (version 10), a common proprietary operating system Linux, representing Unix-like operating systems Windows 10 is installed on the lab computers. A Linux CLI is available by remote connection (through a tool called SSH) to a large server system called Matrix. OPS102 W1C2 - Introduction Part 2 8/21 Command Line and Commands Command Line Interfaces A CLI is provided by two components: A terminal program which accepts user input from a keyboard and displays text output. A shell which interprets commands, starts and stops programs, displays the output of those programs, and enables the user to interact with those programs. These programs are separate so they can be mixed-and-matched for different contexts. OPS102 W1C2 - Introduction Part 2 9/21 Common Shells Bash – a shell widely used on Linux systems, also available on Windows PowerShell – a shell widely used on Windows systems, also available on Linux CMD – a shell available only on Windows systems In this course, we’re going to focus on Bash and CMD. OPS102 W1C2 - Introduction Part 2 10/21 What is a Command? A small number of commands are built into the shell All other commands are separate programs, each contained in its own file. Any GUI or CLI program, including things like the Chrome web browser, git version control tool, or the LibreOffice Writer word processor are also commands! Commands may also be called programs, utilities, applications, or executables – the terms are largely interchangeable. OPS102 W1C2 - Introduction Part 2 11/21 Command Structure Most commands have a smilar structure: command_name arguments... "command_name" is the name of a built-in command, or a separate external program. "arguments..." are zero or more tokens for the command, which could be options, or values for the command to use OPS102 W1C2 - Introduction Part 2 12/21 Type of Arguments Option (also called a Switch or Control Argument) – these alter the operation of the command Option with a Value – as the name indicates, these consist of an option immediately followed by a value Positional Arguments – these are all other arguments, and their position (sequence) may be significant OPS102 W1C2 - Introduction Part 2 13/21 Options – Examples ls # Linux command to list files ls -l # The -l option selects "long" output dir # Windows command to list files dir /b # The /b option selects "bare" output OPS102 W1C2 - Introduction Part 2 14/21 Options – Long and Short Versions (Linux) ls -l -h # Show human-readable sizes ls -l --human-readable # Same thing ls -lh # Same thing OPS102 W1C2 - Introduction Part 2 15/21 Option with a Value ls -l -sort=size # Show files sorted by size (Linux) ls -l -sort time # Show files sorted by time (Linux) dir -o:s # Show files sorted by size (Win10) dir -o t # Show files sorted by time (Win10) dir /o:s # Show files sorted by size (Win10) dir /o t # Show files sorted by time (Win10) OPS102 W1C2 - Introduction Part 2 16/21 Positional Arguments cp old new # Copy file "old" to "new" (Linux) copy old new # Copy file "old" to "new" (Win10) OPS102 W1C2 - Introduction Part 2 17/21 Open Source and Proprietary Software Open Source and Proprietary Software Software is generally protected by copyright, an international legal mechanism that controls how written works may be used. The party which controls these works – either the employer of the author, or the author themselves if outside of an employment context – is the copyright holder. The copyright holder can license the software to another party. OPS102 W1C2 - Introduction Part 2 18/21 Open Source and Proprietary Software There are two broad categories of software licenses in use: Proprietary licenses – the copyright holder provides the software to other parties on a limited basis, often for a fee. The human-readable source code for the software is usually not provided. Open Source Licenses – the copyright holder permits other parties to use the software under one of the licenses that conform to the Open Source Definition (https://opensource.org/osd/). This enables other parties to alter, adapt, change, rebuild, use, and sell the software, subject to certain restrictions. OPS102 W1C2 - Introduction Part 2 19/21 Types of Open Source Licenses Open Source Licenses are further divided into two categories Free Software Licenses – these licenses require anyone redistributing the software to do so under the same terms as the software was received. (https://www.gnu.org/philosophy/free-sw.html.en) Permissive Licenses – these licenses allow the open source software to be redistributed without the same permissions as the software was received under. What are the advantages and disadvantages of each approach? OPS102 W1C2 - Introduction Part 2 20/21 End of Week One! Lots of new ideas and concepts to digest You likely haven’t use the command line much (if at all!) Lots more to come! OPS102 W1C2 - Introduction Part 2 21/21