This document provides an overview of various commands used in the terminal and shell for navigating directories, manipulating files and directories, viewing files, remote connections, variables, and scripts. It lists common commands, their syntax, and what they are used for across these categories to serve as an introduction and reference for using the terminal and shell.

1. Titel
Onderwerp
Verantwoordelijke afdeing, personen.
Datum
JTech Accelerator Program 2019
CI-CD DevOps – Deep Dive
Bert Koorengevel - Java Software Engineer / CodeSmith, Ordina OSD - JTech
@BertKoor

2. 2
 Please tell me …
Why you still need the terminal these days

3. 3
Hardware
Operating System Kernel
CLI GUI Apps
Unix-like Architecture

4. 4
Running sh / bash on a Windows machine
• C:Program Files (x86)Git
• cmd
• git.exe
• git-gui.exe
• bin
• bash.exe
• git.exe
• sh.exe

5. 5
/bin
/dev
/etc
/lib
/tmp
/usr/bin
/usr/lib
/home/bertkoor
~
File System Structure

6. 6
 man [command]
 Google “introduction to unix ohio state university”
 https://devdocs.io/bash/
For help …

7. 7
Command/Syntax What it will do
cd [directory] change directory
ls [options] [directory or file] list directory contents or file permissions
mkdir [options] directory make a directory
pwd print working (current) directory
rmdir [options] directory remove a directory (must be empty)
Directory Navigation

8. 8
Command/Syntax What it will do
chgrp [options] group file change the group of the file
chmod [options] file change file or directory access permissions
chown [options] owner file change the ownership of a file; can only be done by the superuser
cp [options] file1 file2
copy file1 into file2; file2 shouldn't already exist. This command
creates or overwrites file2.
mv [options] file1 file2 move file1 into file2
rm [options] file
remove (delete) a file or directory (-r recursively deletes the directory
and its contents) (-i prompts before removing files)
File Maintenance Commands

9. 9
Command/Syntax What it will do
cat [options] file concatenate (list) a file
echo [text string] echo the text string to stdout
head [-number] file display the first 10 (or number of) lines of a file
more (or less or pg) [options] file page through a text file
tail [options] file display the last few lines (or parts) of a file
Display Commands

10. 10
Command/Syntax What it will do
date [options] report the current date and time
df [options] [resource] report the summary of disk blocks and inodes free and in use
du [options] [directory or file] report amount of disk space in use
hostname/uname display or set (super-user only) the name of the current machine
kill [options] [-SIGNAL] [pid#] [%job]
send a signal to the process with the process id number (pid#) or job
control number (%n). The default signal is to kill the process.
man [options] command show the manual (man) page for a command
passwd [options] set or change your password
ps [options] show status of active processes
which command reports the path to the command or the shell alias in use
who or w report who is logged in and what processes are running
System Resource commands

11. 11
 sh – Bourne shell
 bash – Bourne Again shell
 ksh – Korn shell
 csh – C shell
 fish – Friendly Interface shell
The server is probably not yours, so nothing to choose
Command Line Interfaces

12. 12
Some Bourne shell builtin commands
Command/Syntax What it will do
eval evaluate the given arguments
test evaluate an expression to true or false
set name=value set a variable
exit exit the current shell
if conditional execution
exec execute given command, replacing current shell

13. 13
File Redirection
Symbol Redirection
> redirect output
2> redirect error output
>> append output
| pipe output to another command
< input redirection

14. 14
Command/Syntax What it will do
awk/nawk [options] file scan for patterns in a file and process the results
grep/egrep/fgrep [options] 'search string' file
search the argument (in this case probably a file) for all
occurrences of the search string, and list them.
sed [options] file
stream editor for editing files from a script or from the
command line
Text processing commands

15. 15
Command/Syntax What it will do
cmp [options] file1 file2
compare two files and list where differences occur (text or
binary files)
diff [options] file1 file2
compare the two files and display the differences (text files
only)
find directory [options] [actions] find files matching a type or pattern
sort [options] file sort the lines of the file according to the options chosen
tee [options] file copy stdout to one or more files
touch [options] [date] file
create an empty file, or update the access time of an existing
file
uniq [options] file remove repeated lines in a file
wc [options] [file(s)] display word (or character or line) count for file(s)
File Utilities

16. 16
Command/Syntax What it will do
finger [options]
user[@hostname]
report information about users on local and remote machines
ftp [options] host transfer file(s) using file transfer protocol
rcp [options] hostname remotely copy files from this machine to another machine
rlogin [options] hostname login remotely to another machine
rsh [options] hostname remote shell to run on another machine
telnet [host [port]] communicate with another host using telnet protocol
Remote Connection Commands

17. 17
Variable Usage
$# number of arguments on the command line
$- options supplied to the shell
$? exit value of the last command executed
$$ process number of the current process
$! process number of the last command done in background
$n
argument on the command line, where n is from 1 through
9, reading left to right
$0 the name of the current shell or program
$* all arguments on the command line ("$1 $2 ... $9")
Special Shell Variables

18. 18
#!/bin/sh
if [ $# -ge 2 ]
then
echo $2
elif [ $# -eq 1 ]; then
echo $1
else
echo No input
fi
Scripts