Bash programming - Revision history

wikademia>Wikademia at 08:02, 15 April 2009

2009-04-15T08:02:24Z

← Older revision		Revision as of 08:02, 15 April 2009
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	==The Bash Shell==		==The Bash Shell==
	One of the most powerful tools when using any Unix is the Bash Shell. It is available as either an optional or default shell on most Unix variants. When writing scripts for the Bash Shell, you are creating a file that will be executed by the shell. Bash Scripts are similar in nature to Batch scripts in Microsoft Windows, but allow for much greater functionality.		One of the most powerful tools when using any Unix is the Bash Shell. It is available as either an optional or default shell on most Unix variants. When writing scripts for the Bash Shell, you are creating a file that will be executed by the shell. Bash Scripts are similar in nature to Batch scripts in Microsoft Windows, but allow for much greater functionality.
			{{ntnes}}
	==What does it look like?==		==What does it look like?==
	A sample bash script can be as simple as this:		A sample bash script can be as simple as this:

wikademia>Wikademia: 14 revisions

2009-04-11T05:40:32Z

14 revisions

← Older revision	Revision as of 05:40, 11 April 2009
(No difference)

wikademia>Coffebug: bad contraction or missing word

2009-02-26T15:33:27Z

bad contraction or missing word

← Older revision		Revision as of 15:33, 26 February 2009
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	==The Bash Shell==		==The Bash Shell==
	One of the most powerful tools when using any Unix is the Bash Shell. It is available as either an optional or default shell on most Unix variants. When writing scripts for the Bash Shell, you ~~area~~ file that will be executed by the shell. Bash Scripts are similar in nature to Batch scripts in Microsoft Windows, but allow for much greater functionality.		One of the most powerful tools when using any Unix is the Bash Shell. It is available as either an optional or default shell on most Unix variants. When writing scripts for the Bash Shell, you are creating a file that will be executed by the shell. Bash Scripts are similar in nature to Batch scripts in Microsoft Windows, but allow for much greater functionality.

	==What does it look like?==		==What does it look like?==

wikademia>ChrisSlade: missing '.' inserted into local IP address

2009-02-23T17:12:35Z

missing '.' inserted into local IP address

← Older revision		Revision as of 17:12, 23 February 2009
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	#!/bin/bash		#!/bin/bash
	alias nmp="nmap -vv -T Insane -P0 -O"		alias nmp="nmap -vv -T Insane -P0 -O"
	nmp 127.0.01		nmp 127.0.0.1
	</source>		</source>

192.117.106.24: /* Loops */

2008-12-02T18:30:58Z

Loops

← Older revision		Revision as of 18:30, 2 December 2008
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	read NAMES		read NAMES
	for i in $NAMES; do		for i in $NAMES; do
	echo "Hi there $i, pleased to meet you."		echo "Hi there $i, pleased to meet you."
	done		done
	</source>		</source>

wikademia>Pdufautl: Updated some terminology, changed the examples to be a bit more specific. Still don't like the nmap reference here, but can't think of a better example right now.

2008-02-12T01:28:00Z

Updated some terminology, changed the examples to be a bit more specific. Still don't like the nmap reference here, but can't think of a better example right now.

← Older revision		Revision as of 01:28, 12 February 2008
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	==The Bash Shell==		==The Bash Shell==
	One of the most powerful tools when using any Unix is the Bash Shell. It is available as either an optional or default shell on most Unix variants. When ~~coding~~ for the Bash Shell, you ~~are writing scripts~~ that will be executed by the shell. Bash Scripts are similar in nature to Batch scripts in Windows, but go much ~~deeper into the operation of the OS~~.		One of the most powerful tools when using any Unix is the Bash Shell. It is available as either an optional or default shell on most Unix variants. When writing scripts for the Bash Shell, you area file that will be executed by the shell. Bash Scripts are similar in nature to Batch scripts in Microsoft Windows, but allow for much greater functionality.

	==What does it look like?==		==What does it look like?==
	~~The Bash Shell syntax works very much like Batch, in that you use terminal commands.~~ A sample script can be as simple as		A sample bash script can be as simple as this:
	<source lang="bash">		<source lang="bash">
	#!/bin/bash		#!/bin/bash
	echo "~~hello world~~!"		echo "Hello World!"
	</source>		</source>
	~~and~~ can be as complex as script designed to ~~ping a DNS server to retrieve an IP~~. A typical Bash Script is used to automate monotonous tasks like scanning ~~folders~~ and deleting automatically backed up files, or setting permissions to new files.		Alternatively, it can be as complex as script designed to install and configure whole operating systems or troubleshoot problematic servers. A typical Bash Script is used to automate monotonous tasks like scanning directories and deleting automatically backed up files, or setting permissions to new files.

	==How do you make a Bash Script?==		==How do you make a Bash Script?==
	To begin the coding of a Bash Script, all one needs is a text editor (such as Gedit or VI). ~~Head~~ the file ~~off~~ with: <source lang="bash">#!/bin/bash</source> (~~this~~ varies by Unix variant, and depends on the placement of the bash binary). Then one would write the commands or arguments that need to be performed, such as: <source lang="bash">alias nmp="nmap -vv -T Insane -P0 -O"</source>		To begin the coding of a Bash Script, all one needs is a text editor (such as Gedit or vi/vim, emacs, nano, jed, etc). Start off the file with:
	That example makes a script that eases the use of the Nmap Port Scanner. It uses a function called aliasing, which allows complex commands to be simplified by using another sequence, ~~and are commonly~~ used ~~in startup scripts~~. ~~The~~ finished ~~product~~ would look something like:		<source lang="bash">#!/bin/bash</source>
			(This varies by Unix variant, and depends on the placement of the bash binary. To find out what the path to the bash binary is, use this command: which bash ).
			Then one would write the commands or arguments that need to be performed, such as:
			<source lang="bash">alias nmp="nmap -vv -T Insane -P0 -O"</source>
			That example makes a script that eases the use of the Nmap Port Scanner. It uses a function called aliasing, which allows complex commands to be simplified by using another sequence. Next, you can call the alias to do work -- an alias is used like a constant from other programming languages, except it's used to execute programs. So, for a finished script to scan your own computer, it would look something like this:
	<source lang="bash">		<source lang="bash">
	#!/bin/bash		#!/bin/bash
	alias nmp="nmap -vv -T Insane -P0 -O"		alias nmp="nmap -vv -T Insane -P0 -O"
			nmp 127.0.01
	</source>		</source>

	==Interactive Input==		==Interactive Input==
	Taking user input is invaluable when writing an application. ~~Recieving~~ and interpreting a user's input is a simple task in Bash scripting. All that is needed is to declare a variable to read, and use it for something. An easy way to explain this would be to ask for a user's name, and display it:		Taking user input is invaluable when writing an application. Receiving and interpreting a user's input is a simple task in Bash scripting. All that is needed is to declare a variable to read, and use it for something. An easy way to explain this would be to ask for a user's name, and display it:
	<source lang="bash">		<source lang="bash">
	#!/bin/bash		#!/bin/bash
	echo ~~enter~~ your name please:		echo "Enter your name please:"
	read NAME		read NAME
	echo ~~your name is~~ $NAME		echo "Hi there $NAME, pleased to meet you."
	</source>		</source>

Line 29:		Line 36:
	<source lang="bash">		<source lang="bash">
	#!/bin/bash		#!/bin/bash
	~~while true; do~~		echo "Please enter a list of names to greet"
	echo enter ~~an address~~ to ~~scan:~~		read NAMES
	read ~~ADDR~~		for i in $NAMES; do
	~~nmap -vv -T Insane -P0 -O~~ $~~ADDR~~		echo "Hi there $i, pleased to meet you."
	done		done
	</source>		</source>

			==More complicated stuff==
	[[Category:Linux]]		[[Category:Linux]]
	[[Category:Programming]]		[[Category:Programming]]

wikademia>HappyCamper: Bash Programming moved to Bash programming: casing

2008-01-05T22:32:18Z

Bash Programming moved to Bash programming: casing

← Older revision		Revision as of 22:32, 5 January 2008
(No difference)

wikademia>Historybuff at 20:12, 24 November 2007

2007-11-24T20:12:43Z

← Older revision		Revision as of 20:12, 24 November 2007
Line 1:		Line 1:
	==Bash Shell==		==The Bash Shell==
	One of the most powerful tools when using any Unix is the Bash Shell. It is available as either an optional or default shell on most Unix variants. When coding for the Bash Shell, you are writing scripts that will be executed by the shell. Bash Scripts are similar in nature to Batch scripts in Windows, but go much deeper into the operation of the OS.		One of the most powerful tools when using any Unix is the Bash Shell. It is available as either an optional or default shell on most Unix variants. When coding for the Bash Shell, you are writing scripts that will be executed by the shell. Bash Scripts are similar in nature to Batch scripts in Windows, but go much deeper into the operation of the OS.
	==What does it look like?==		==What does it look like?==

wikademia>Historybuff: /* Input */ talk to the user

2007-11-16T21:39:56Z

Input: talk to the user

← Older revision		Revision as of 21:39, 16 November 2007
Line 16:		Line 16:
	</source>		</source>

	==Input==		==Interactive Input==
	Taking user input is invaluable when ~~making~~ an application. Recieving and interpreting a user's input is a simple task in Bash scripting. All that is needed is to declare a variable to read, and use it for something. An easy way to explain this would be to ask for a user's name, and display it:		Taking user input is invaluable when writing an application. Recieving and interpreting a user's input is a simple task in Bash scripting. All that is needed is to declare a variable to read, and use it for something. An easy way to explain this would be to ask for a user's name, and display it:
	<source lang="bash">		<source lang="bash">
	#!/bin/bash		#!/bin/bash
Line 24:		Line 24:
	echo your name is $NAME		echo your name is $NAME
	</source>		</source>

	==Loops==		==Loops==
	Loops are an essential part to many programming languages, and this holds true for Bash scripting as well. A simple way to incorporate a loop into a Bash script would look like this:		Loops are an essential part to many programming languages, and this holds true for Bash scripting as well. A simple way to incorporate a loop into a Bash script would look like this:

wikademia>Historybuff: /* How do you make a Bash Script? */

2007-11-16T21:36:59Z

How do you make a Bash Script?

← Older revision		Revision as of 21:36, 16 November 2007
Line 10:		Line 10:
	==How do you make a Bash Script?==		==How do you make a Bash Script?==
	To begin the coding of a Bash Script, all one needs is a text editor (such as Gedit or VI). Head the file off with: <source lang="bash">#!/bin/bash</source> (this varies by Unix variant, and depends on the placement of the bash binary). Then one would write the commands or arguments that need to be performed, such as: <source lang="bash">alias nmp="nmap -vv -T Insane -P0 -O"</source>		To begin the coding of a Bash Script, all one needs is a text editor (such as Gedit or VI). Head the file off with: <source lang="bash">#!/bin/bash</source> (this varies by Unix variant, and depends on the placement of the bash binary). Then one would write the commands or arguments that need to be performed, such as: <source lang="bash">alias nmp="nmap -vv -T Insane -P0 -O"</source>
	That example makes a script that eases the use of the Nmap Port Scanner. The finished product would look something like:		That example makes a script that eases the use of the Nmap Port Scanner. It uses a function called aliasing, which allows complex commands to be simplified by using another sequence, and are commonly used in startup scripts. The finished product would look something like:
	<source lang="bash">		<source lang="bash">
	#!/bin/bash		#!/bin/bash
	alias nmp="nmap -vv -T Insane -P0 -O"		alias nmp="nmap -vv -T Insane -P0 -O"
	</source>		</source>

	==Input==		==Input==
	Taking user input is invaluable when making an application. Recieving and interpreting a user's input is a simple task in Bash scripting. All that is needed is to declare a variable to read, and use it for something. An easy way to explain this would be to ask for a user's name, and display it:		Taking user input is invaluable when making an application. Recieving and interpreting a user's input is a simple task in Bash scripting. All that is needed is to declare a variable to read, and use it for something. An easy way to explain this would be to ask for a user's name, and display it: