Introduction to Linux Commands

1. Introduction to Linux Commands

2. Shells • Create processes that execute user commands. • bash • sh • csh • tcsh • ksh

3. Commands • Typically, programs. Format: $ command [command-options(s)] arguments … Some commands options have their own arguments. • Ex. ls –l *.dat fgrep –i foot f1.dat f2.dat f3.dat • Help is available. man ls

4. Categories • Files/file system • Processes • Networking • Program development • Misc.

5. cat cd chmod cp fgrep find gzip/gunzip head ls mkdir more mv od pwd rm tail tar wc Files/file system

6. Processes • & • ctrl-z, bg, fg • kill • nice, renice • ps • top

7. Networking • ftp • hostname • ping • ssh • traceroute

8. Program development • g++ • gdb • gprof • make • sccs, cvs • talk • vi

9. Misc. • date • echo • exit • history • man • sort • which • who • whoami

10. Pipes and I/O redirection • Programs (including commands) typically read from stdin (typically the keyboard) and write to stdout (typically the screen/window).

11. Input redirection • Input redirection is used to make input come from a file. sort 12 1 19 ctrl-d sort < junk.data sort junk.data

12. Output redirection • Output redirection is used to make output go to a file. sort junk.data sort junk.data > junk-sorted.data

13. Pipes • Chain the output of one program to the input of another. • Ex. fgrep –i xray f1.dat f2.data … fn.dat | more ls -l | fgrep –i chest | fgrep –i xray > results.txt

14. Windows • Windows has a rudimentary shell called the command prompt. • It supports pipes and I/O redirection as well (using the exact same characters: |, <, and >).