GPL-3-Free Replacements of Coreutils 1 Contents
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At—At, Batch—Execute Commands at a Later Time
at—at, batch—execute commands at a later time at [–csm] [–f script] [–qqueue] time [date] [+ increment] at –l [ job...] at –r job... batch at and batch read commands from standard input to be executed at a later time. at allows you to specify when the commands should be executed, while jobs queued with batch will execute when system load level permits. Executes commands read from stdin or a file at some later time. Unless redirected, the output is mailed to the user. Example A.1 1 at 6:30am Dec 12 < program 2 at noon tomorrow < program 3 at 1945 pm August 9 < program 4 at now + 3 hours < program 5 at 8:30am Jan 4 < program 6 at -r 83883555320.a EXPLANATION 1. At 6:30 in the morning on December 12th, start the job. 2. At noon tomorrow start the job. 3. At 7:45 in the evening on August 9th, start the job. 4. In three hours start the job. 5. At 8:30 in the morning of January 4th, start the job. 6. Removes previously scheduled job 83883555320.a. awk—pattern scanning and processing language awk [ –fprogram–file ] [ –Fc ] [ prog ] [ parameters ] [ filename...] awk scans each input filename for lines that match any of a set of patterns specified in prog. Example A.2 1 awk '{print $1, $2}' file 2 awk '/John/{print $3, $4}' file 3 awk -F: '{print $3}' /etc/passwd 4 date | awk '{print $6}' EXPLANATION 1. Prints the first two fields of file where fields are separated by whitespace. 2. Prints fields 3 and 4 if the pattern John is found. -
Unix Introduction
Unix introduction Mikhail Dozmorov Summer 2018 Mikhail Dozmorov Unix introduction Summer 2018 1 / 37 What is Unix Unix is a family of operating systems and environments that exploits the power of linguistic abstractions to perform tasks Unix is not an acronym; it is a pun on “Multics”. Multics was a large multi-user operating system that was being developed at Bell Labs shortly before Unix was created in the early ’70s. Brian Kernighan is credited with the name. All computational genomics is done in Unix http://www.read.seas.harvard.edu/~kohler/class/aosref/ritchie84evolution.pdfMikhail Dozmorov Unix introduction Summer 2018 2 / 37 History of Unix Initial file system, command interpreter (shell), and process management started by Ken Thompson File system and further development from Dennis Ritchie, as well as Doug McIlroy and Joe Ossanna Vast array of simple, dependable tools that each do one simple task Ken Thompson (sitting) and Dennis Ritchie working together at a PDP-11 Mikhail Dozmorov Unix introduction Summer 2018 3 / 37 Philosophy of Unix Vast array of simple, dependable tools Each do one simple task, and do it really well By combining these tools, one can conduct rather sophisticated analyses The Linux help philosophy: “RTFM” (Read the Fine Manual) Mikhail Dozmorov Unix introduction Summer 2018 4 / 37 Know your Unix Unix users spend a lot of time at the command line In Unix, a word is worth a thousand mouse clicks Mikhail Dozmorov Unix introduction Summer 2018 5 / 37 Unix systems Three common types of laptop/desktop operating systems: Windows, Mac, Linux. Mac and Linux are both Unix-like! What that means for us: Unix-like operating systems are equipped with “shells”" that provide a command line user interface. -
A Postgresql Development Environment
A PostgreSQL development environment Peter Eisentraut [email protected] @petereisentraut The plan tooling building testing developing documenting maintaining Tooling: Git commands Useful commands: git add (-N, -p) git ls-files git am git format-patch git apply git grep (-i, -w, -W) git bisect git log (-S, --grep) git blame -w git merge git branch (--contains, -d, -D, --list, git pull -m, -r) git push (-n, -f, -u) git checkout (file, branch, -b) git rebase git cherry-pick git reset (--hard) git clean (-f, -d, -x, -n) git show git commit (--amend, --reset, -- git status fixup, -a) git stash git diff git tag Tooling: Git configuration [diff] colorMoved = true colorMovedWS = allow-indentation-change [log] date = local [merge] conflictStyle = diff3 [rebase] autosquash = true [stash] showPatch = true [tag] sort = version:refname [versionsort] suffix = "_BETA" suffix = "_RC" Tooling: Git aliases [alias] check-whitespace = \ !git diff-tree --check $(git hash-object -t tree /dev/null) HEAD ${1:-$GIT_PREFIX} find = !git ls-files "*/$1" gtags = !git ls-files | gtags -f - st = status tags = tag -l wdiff = diff --color-words=[[:alnum:]]+ wshow = show --color-words Tooling: Git shell integration zsh vcs_info Tooling: Editor Custom settings for PostgreSQL sources exist. Advanced options: whitespace checking automatic spell checking (flyspell) automatic building (flycheck, flymake) symbol lookup ("tags") Tooling: Shell settings https://superuser.com/questions/521657/zsh-automatically-set-environment-variables-for-a-directory zstyle ':chpwd:profiles:/*/*/devel/postgresql(|/|/*)' profile postgresql chpwd_profile_postgresql() { chpwd_profile_default export EMAIL="[email protected]" alias nano='nano -T4' LESS="$LESS -x4" } Tooling — Summary Your four friends: vcs editor shell terminal Building: How to run configure ./configure -C/--config-cache --prefix=$(cd . -
UNIX Cheat Sheet – Sarah Medland Help on Any Unix Command List a Directory Change to Directory Make a New Directory Remove A
THE 2013 INTERNATIONAL WORKSHOP ON STATISTICAL METHODOLOGY FOR HUMAN GENOMIC STUDIES UNIX cheat sheet – Sarah Medland Help on any Unix command man {command} Type man ls to read the manual for the ls command. which {command} Find out where a program is installed whatis {command} Give short description of command. List a directory ls {path} ls -l {path} Long listing, with date, size and permisions. ls -R {path} Recursive listing, with all subdirs. Change to directory cd {dirname} There must be a space between. cd ~ Go back to home directory, useful if you're lost. cd .. Go back one directory. Make a new directory mkdir {dirname} Remove a directory/file rmdir {dirname} Only works if {dirname} is empty. rm {filespec} ? and * wildcards work like DOS should. "?" is any character; "*" is any string of characters. Print working directory pwd Show where you are as full path. Copy a file or directory cp {file1} {file2} cp -r {dir1} {dir2} Recursive, copy directory and all subdirs. cat {newfile} >> {oldfile} Append newfile to end of oldfile. Move (or rename) a file mv {oldfile} {newfile} Moving a file and renaming it are the same thing. View a text file more {filename} View file one screen at a time. less {filename} Like more , with extra features. cat {filename} View file, but it scrolls. page {filename} Very handy with ncftp . nano {filename} Use text editor. head {filename} show first 10 lines tail {filename} show last 10 lines Compare two files diff {file1} {file2} Show the differences. sdiff {file1} {file2} Show files side by side. Other text commands grep '{pattern}' {file} Find regular expression in file. -
Introduction to Linux – Part 1
Introduction to Linux – Part 1 Brett Milash and Wim Cardoen Center for High Performance Computing May 22, 2018 ssh Login or Interactive Node kingspeak.chpc.utah.edu Batch queue system … kp001 kp002 …. kpxxx FastX ● https://www.chpc.utah.edu/documentation/software/fastx2.php ● Remote graphical sessions in much more efficient and effective way than simple X forwarding ● Persistence - can be disconnected from without closing the session, allowing users to resume their sessions from other devices. ● Licensed by CHPC ● Desktop clients exist for windows, mac, and linux ● Web based client option ● Server installed on all CHPC interactive nodes and the frisco nodes. Windows – alternatives to FastX ● Need ssh client - PuTTY ● http://www.chiark.greenend.org.uk/~sgtatham/putty/download.html - XShell ● http://www.netsarang.com/download/down_xsh.html ● For X applications also need X-forwarding tool - Xming (use Mesa version as needed for some apps) ● http://www.straightrunning.com/XmingNotes/ - Make sure X forwarding enabled in your ssh client Linux or Mac Desktop ● Just need to open up a terminal or console ● When running applications with graphical interfaces, use ssh –Y or ssh –X Getting Started - Login ● Download and install FastX if you like (required on windows unless you already have PuTTY or Xshell installed) ● If you have a CHPC account: - ssh [email protected] ● If not get a username and password: - ssh [email protected] Shell Basics q A Shell is a program that is the interface between you and the operating system -
Lecture 7 Network Management and Debugging
SYSTEM ADMINISTRATION MTAT.08.021 LECTURE 7 NETWORK MANAGEMENT AND DEBUGGING Prepared By: Amnir Hadachi and Artjom Lind University of Tartu, Institute of Computer Science [email protected] / [email protected] 1 LECTURE 7: NETWORK MGT AND DEBUGGING OUTLINE 1.Intro 2.Network Troubleshooting 3.Ping 4.SmokePing 5.Trace route 6.Network statistics 7.Inspection of live interface activity 8.Packet sniffers 9.Network management protocols 10.Network mapper 2 1. INTRO 3 LECTURE 7: NETWORK MGT AND DEBUGGING INTRO QUOTE: Networks has tendency to increase the number of interdependencies among machine; therefore, they tend to magnify problems. • Network management tasks: ✴ Fault detection for networks, gateways, and critical servers ✴ Schemes for notifying an administrator of problems ✴ General network monitoring, to balance load and plan expansion ✴ Documentation and visualization of the network ✴ Administration of network devices from a central site 4 LECTURE 7: NETWORK MGT AND DEBUGGING INTRO Network Size 160 120 80 40 Management Procedures 0 AUTOMATION ILLUSTRATION OF NETWORK GROWTH VS MGT PROCEDURES AUTOMATION 5 LECTURE 7: NETWORK MGT AND DEBUGGING INTRO • Network: • Subnets + Routers / switches Time to consider • Automating mgt tasks: • shell scripting source: http://www.eventhelix.com/RealtimeMantra/Networking/ip_routing.htm#.VvjkA2MQhIY • network mgt station 6 2. NETWORK TROUBLES HOOTING 7 LECTURE 7: NETWORK MGT AND DEBUGGING NETWORK TROUBLESHOOTING • Many tools are available for debugging • Debugging: • Low-level (e.g. TCP/IP layer) • high-level (e.g. DNS, NFS, and HTTP) • This section progress: ping trace route GENERAL ESSENTIAL TROUBLESHOOTING netstat TOOLS STRATEGY nmap tcpdump … 8 LECTURE 7: NETWORK MGT AND DEBUGGING NETWORK TROUBLESHOOTING • Before action, principle to consider: ✴ Make one change at a time ✴ Document the situation as it was before you got involved. -
Unix Command Line; Editors
Unix command line; editors Karl Broman Biostatistics & Medical Informatics, UW–Madison kbroman.org github.com/kbroman @kwbroman Course web: kbroman.org/AdvData My goal in this lecture is to convince you that (a) command-line-based tools are the things to focus on, (b) you need to choose a powerful, universal text editor (you’ll use it a lot), (c) you want to be comfortable and skilled with each. For your work to be reproducible, it needs to be code-based; don’t touch that mouse! Windows vs. Mac OSX vs. Linux Remote vs. Not 2 The Windows operating system is not very programmer-friendly. Mac OSX isn’t either, but under the hood, it’s just unix. Don’t touch the mouse! Open a terminal window and start typing. I do most of my work directly on my desktop or laptop. You might prefer to work remotely on a server, instead. But I can’t stand having any lag in looking at graphics. If you use Windows... Consider Git Bash (or Cygwin) or turn on the Windows subsystem for linux 3 Cygwin is an effort to get Unix command-line tools in Windows. Git Bash combines git (for version control) and bash (the unix shell); it’s simpler to deal with than Cygwin. Linux is now accessible in Windows 10, but you have to enable it. If you use a Mac... Consider Homebrew and iTerm2 Also the XCode command line tools 4 Homebrew is a packaging system; iTerm2 is a Terminal replacement. The XCode command line tools are a must for most unixy things on a Mac. -
Making Linux Protection Mechanisms Egalitarian with Userfs
Making Linux Protection Mechanisms Egalitarian with UserFS Taesoo Kim and Nickolai Zeldovich MIT CSAIL ABSTRACT firewall rules, forcing applications to invent their own UserFS provides egalitarian OS protection mechanisms protection techniques like system call interposition [15], in Linux. UserFS allows any user—not just the system binary rewriting [30] or analysis [13, 45], or interposing administrator—to allocate Unix user IDs, to use chroot, on system accesses in a language runtime like Javascript. and to set up firewall rules in order to confine untrusted This paper presents the design of UserFS, a kernel code. One key idea in UserFS is representing user IDs as framework that allows any application to use traditional files in a /proc-like file system, thus allowing applica- OS protection mechanisms on a Unix system, and a proto- tions to manage user IDs like any other files, by setting type implementation of UserFS for Linux. UserFS makes permissions and passing file descriptors over Unix do- protection mechanisms egalitarian, so that any user—not main sockets. UserFS addresses several challenges in just the system administrator—can allocate new user IDs, making user IDs egalitarian, including accountability, re- set up firewall rules, and isolate processes using chroot. source allocation, persistence, and UID reuse. We have By using the operating system’s own protection mecha- ported several applications to take advantage of UserFS; nisms, applications can avoid race conditions and ambi- by changing just tens to hundreds of lines of code, we guities associated with system call interposition [14, 43], prevented attackers from exploiting application-level vul- can confine existing code without having to recompile or nerabilities, such as code injection or missing ACL checks rewrite it in a new language, and can enforce a coherent in a PHP-based wiki application. -
Sandboxing 2 Change Root: Chroot()
Sandboxing 2 Change Root: chroot() Oldest Unix isolation mechanism Make a process believe that some subtree is the entire file system File outside of this subtree simply don’t exist Sounds good, but. Sandboxing 2 2 / 47 Chroot Sandboxing 2 3 / 47 Limitations of Chroot Only root can invoke it. (Why?) Setting up minimum necessary environment can be painful The program to execute generally needs to live within the subtree, where it’s exposed Still vulnerable to root compromise Doesn’t protect network identity Sandboxing 2 4 / 47 Root versus Chroot Suppose an ordinary user could use chroot() Create a link to the sudo command Create /etc and /etc/passwd with a known root password Create links to any files you want to read or write Besides, root can escape from chroot() Sandboxing 2 5 / 47 Escaping Chroot What is the current directory? If it’s not under the chroot() tree, try chdir("../../..") Better escape: create device files On Unix, all (non-network) devices have filenames Even physical memory has a filename Create a physical memory device, open it, and change the kernel data structures to remove the restriction Create a disk device, and mount a file system on it. Then chroot() to the real root (On Unix systems, disks other than the root file system are “mounted” as a subtree somewhere) Sandboxing 2 6 / 47 Trying Chroot # mkdir /usr/sandbox /usr/sandbox/bin # cp /bin/sh /usr/sandbox/bin/sh # chroot /usr/sandbox /bin/sh chroot: /bin/sh: Exec format error # mkdir /usr/sandbox/libexec # cp /libexec/ld.elf_so /usr/sandbox/libexec # chroot /usr/sandbox -
General Education and Liberal Studies Course List
GELS 2020–2021 General Education/Liberal Studies/Minnesota Transfer Curriculum 2020–2021 Course List This course list is current as of March 25, 2021. For the most current information view the Current GELS/MnTC list on the Class Schedule page at www.metrostate.edu. This is the official list of Metropolitan State University courses that meet the General Education and Liberal Studies (GELS) requirements for all undergraduate students admitted to the university. To meet the university’s General Education and Liberal Studies (GELS) requirements, students must complete each of the 10 goal areas of the Minnesota Transfer Curriculum (MnTC) and complete 48 unduplicated credits. Eight (8) of the 48 credits must be upper division (300-level or higher) to fulfill the university’s Liberal Studies requirement. Each course title is followed by a number in parenthesis (4). This number indicates the number of credits for that course. Course titles followed by more than one number, such as (2-4), indicate a variable-credit course. Superscript Number: • Superscript number (10) indicates that a course meets more than one goal area requirement. For example, NSCI 20410 listed under Goal 3 meets Goals 3 and 10. Although the credits count only once, the course satisfies the two goal area requirements. • Separated by a comma (3,LS) indicates that a course will meet both areas indicated. • Separated by a forward slash (7/8) indicates that a course will meet one or the other goal area but not both. Superscript LS (LS): • Indicates that a course will meet the Liberal Studies requirement. Asterisk (*): • Indicates that a course can be used to meet goal area requirements, but cannot be used as General Education or Liberal Studies Electives. -
Penndot Form MV-409
MV-409 (3-18) www.dmv.pa.gov APPLICATION FOR CERTIFICATION OF For Department Use Only BureauP.O. Box of Motor 68697 Vehicles Harrisburg, • Vehicle PAInspection 17106-8697 Division OFFICIAL VEHICLE SAFETY INSPECTOR • PRINT OR TYPE ALL INFORMATION - MUST BE SUBMITTED TO AN APPROVED EDUCATIONAL FACILITY Applicant must be 18 years of age and have a valid operator’s license for each class of vehicle he/she intends to inspect. Applicant must also complete a lecture course at an approved educational facility, pass a written test and satisfactorily perform a complete inspection of a vehicle. upon successful completion of these courses, you will receive your certified safety inspection certification card in approximately 6 to 8 weeks from the date your class ended. The school has 35 days from the class ending date to submit the paperwork for processing. You may not begin inspecting until you receive your certification card. A APPLICANT INFORMATION Last Name First Name Middle Name Sex birth Date Driver’s License Number State r M r F Street Address City State County Zip Code Work Telephone Number Home Telephone Number Do you currently hold a valid out-of-state driver’s license? (If yes, attach a copy.) . r Yes r No *Contact PennDOT’s Vehicle Inspection Division at 717-787-2895 to establish an out-of-state mechanic record prior to completion of this class. List any restrictions on your driver’s license (if applicable): ______________________________________________________________ Do you currently hold a valid Pennsylvania driver’s license? . r Yes r No Have you held a Pennsylvania driver’s license in the past? . -
LINUX INTERNALS LABORATORY III. Understand Process
LINUX INTERNALS LABORATORY VI Semester: IT Course Code Category Hours / Week Credits Maximum Marks L T P C CIA SEE Total AIT105 Core - - 3 2 30 70 100 Contact Classes: Nil Tutorial Classes: Nil Practical Classes: 36 Total Classes: 36 OBJECTIVES: The course should enable the students to: I. Familiar with the Linux command-line environment. II. Understand system administration processes by providing a hands-on experience. III. Understand Process management and inter-process communications techniques. LIST OF EXPERIMENTS Week-1 BASIC COMMANDS I Study and Practice on various commands like man, passwd, tty, script, clear, date, cal, cp, mv, ln, rm, unlink, mkdir, rmdir, du, df, mount, umount, find, unmask, ulimit, ps, who, w. Week-2 BASIC COMMANDS II Study and Practice on various commands like cat, tail, head , sort, nl, uniq, grep, egrep,fgrep, cut, paste, join, tee, pg, comm, cmp, diff, tr, awk, tar, cpio. Week-3 SHELL PROGRAMMING I a) Write a Shell Program to print all .txt files and .c files. b) Write a Shell program to move a set of files to a specified directory. c) Write a Shell program to display all the users who are currently logged in after a specified time. d) Write a Shell Program to wish the user based on the login time. Week-4 SHELL PROGRAMMING II a) Write a Shell program to pass a message to a group of members, individual member and all. b) Write a Shell program to count the number of words in a file. c) Write a Shell program to calculate the factorial of a given number.