Linux Command-Line for Analysts and Operators

Getting Around

• • The Linux file system

• • cd, pwd, and ls

• • Relative vs absolute pathnames

• • Tab completion

• • <<LAB>> Directory Jeopardy!

Basic Commands

• • File manipulation (cp, mv, and rm)

• • Getting to know ls

• • Getting help

• • Command history searching and editing

• • cat and less

• • Effective use of wildcards

• • su and sudo

• • <<LAB>> Only Seven Commands? No Worries!

Building Blocks

• • The Unix/Linux command design

• • Slicing and dicing (cut and awk)

• • Selecting (grep)

• • Sorting and collecting (sort and uniq)

• • Sampling (head, tail, wc)

• • <<LAB>> Learning to Linux

Output Redirection

• • stdin, stdout, stderr

• • Best practices

• • Output splitting (tee)

• • Argument substitution (“$(…)”)

• • <<LAB>> Redirect This!

Loops

• • The humble echo statement

• • Simple wildcard loops

• • Loops in pipelines

• • Other argument lists

• • Reading from files

• • Field splitting

• • <<LAB>> Get in the Loop

Conditionals

• • “if … then”

• • Short-circuit operations

• • Test operator (“[[…]]”)

• • <<LAB>> Choose Your Own Adventure

Other Iterators

• • Implicit loop operations (awk, grep)

• • find command

• • Adding xargs

• • Dealing with whitespace in file names

• • <<LAB>> Find All the Things!

Regular Expressions

• • Basic regular expressions

• • Extended regular expression syntax

• • When to use which syntax

• • <<LAB>> Express Yourself

AWK, sed, and tr

• • Advanced selection with awk

• • Transforming strings with sed

• • Easy transforms with tr

• • <<LAB>> Transformers

Processes

• • The different modes of ps

• • Seeing network information (netstat)

• • Terminating processes (kill, pkill)

• • Process priority (renice)

• • All hail lsof

• • Best of /proc

• • <<LAB>> Processing

Users, Groups, and Permissions

• • Understanding users and groups

• • Command interface (id, who, whoami, groups)

• • File ownership

• • File permissions

• • With chown, chgrp, chmod, and find

• • About umask

• • <<LAB>> Mine, Ours, Theirs