Shell scripting - Revision history

Lilith2: /* Hello World */

2015-09-23T22:09:46Z

‎Hello World

Lilith2: /* Hello World */

2015-09-23T22:09:09Z

‎Hello World

Lilith2: /* Shells */

2015-09-23T20:54:07Z

‎Shells

Lilith2: /* Hello World */

2015-09-23T20:51:31Z

‎Hello World

Lilith2: /* Hello World */

2015-09-23T20:49:44Z

‎Hello World

Alex at 08:34, 11 September 2015

2015-09-11T08:34:48Z

Lilith2 at 08:31, 22 August 2015

2015-08-22T08:31:12Z

Lilith2 at 10:56, 15 July 2015

2015-07-15T10:56:21Z

Lilith2 at 15:18, 13 July 2015

2015-07-13T15:18:12Z

Lilith2: /* Testing */

2015-07-11T16:33:01Z

‎Testing

@@ Line 43: / Line 43: @@
   /usr/local/bin:/usr/bin:/bin:/usr/local/games:/usr/games:/home/user/bin</pre>
-Not you can just call your script with:
+Not you can just call your script from anywhere in your file system with:
   $ helloworld.sh

@@ Line 10: / Line 10: @@
 == Hello World ==
 Shell scripts are text files that can be created with your favourite text editor.
@@ Line 41: / Line 40: @@
 Check that it is in your path with:
- $ echo $PATH
+<pre>$ echo $PATH
-  /usr/local/bin:/usr/bin:/bin:/usr/local/games:/usr/games:/home/user/bin
+  /usr/local/bin:/usr/bin:/bin:/usr/local/games:/usr/games:/home/user/bin</pre>
 That <code>PATH</code> is a socalled environment variable.
 ''Note: Do not put a dot <code>.</code> in the <code>PATH</code> environment variable to indicate commands can be run from the current directory. It can override well known commands if the name of your script is the same. A major security issue.
 == Print system related information ==

@@ Line 2: / Line 2: @@
 == Shells ==
-Unix has variety of Shells. Bourne shell (sh), Bourne again shell (bash), C shell (csh), Korn shell (ksh), Tenex C shell (tcsh). Use the which or whereis unix commands to find out where a specific shell is located:
+Unix has variety of Shells. Bourne shell (sh), Bourne again shell (bash), C shell (csh), Korn shell (ksh), Tenex C shell (tcsh). Use the <code>which</code> or <code>whereis</code> unix commands to find out where a specific shell is located:
- # which bash
+<pre># which bash
- /bin/bash
+/bin/bash</pre>
 or:
- # whereis bash
+<pre># whereis bash
- bash: /bin/bash /etc/bash.bashrc /usr/share/man/man1/bash.1.gz
+bash: /bin/bash /etc/bash.bashrc /usr/share/man/man1/bash.1.gz</pre>
 == Hello World ==

@@ Line 30: / Line 30: @@
 Now you can run it with:
- $ ./helloworld.sh
+<pre>$ ./helloworld.sh
-Hello World
+Hello World</pre>
 And that only works if you are in the directory that contains the script. By putting the directory containing executable scripts in your <code>PATH</code>, it can be identified by its full or relative path and you can run it from anywhere in your system.

← Older revision		Revision as of 20:49, 23 September 2015
Line 10:		Line 10:

	== Hello World ==		== Hello World ==
		+
		+	Shell scripts are text files that can be created with your favourite text editor.
		+
		+	$ geany helloworld.sh
		+
		+	In the file have this:
		+
		+	<pre>#!/bin/bash
		+	echo "Hello World"</pre>
		+
		+	The first line should always have that <code>#!/bin/bash</code>. The <code>#</code> starts a comment. The <code>#!</code> syntax acts as a comment for shells that do not understand this syntax. The <code>/bin/bash</code> tells any running shell, bash or other, which program to use to run the script, in this case bash. Not all systems have a bash shell, in which case you will find <code>/bin/sh</code> instead.
		+
		+	Save.
		+
		+	To run the file it must first be made executable:
		+
		+	$ chmod u+r helloworld.sh
		+
		+	Now you can run it with:
		+
		+	$ ./helloworld.sh
		+	Hello World
		+
		+	And that only works if you are in the directory that contains the script. By putting the directory containing executable scripts in your <code>PATH</code>, it can be identified by its full or relative path and you can run it from anywhere in your system.
		+
		+	Most modern Linux distributions encourage a practice in which each user has a specific directory for the programs and scripts he/she personally uses. This directory is called bin and is a subdirectory of your home directory.
		+
		+	$ mkdir ~/bin; cp helloworld.sh ~/bin/; PATH=$PATH:~/bin
		+
		+	Check that it is in your path with:
		+
		+	$ echo $PATH
		+	/usr/local/bin:/usr/bin:/bin:/usr/local/games:/usr/games:/home/user/bin
		+
		+	That <code>PATH</code> is a socalled environment variable.
		+
		+	''Note: Do not put a dot <code>.</code> in the <code>PATH</code> environment variable to indicate commands can be run from the current directory. It can override well known commands if the name of your script is the same. A major security issue.

	== Print system related information ==		== Print system related information ==

← Older revision		Revision as of 08:34, 11 September 2015
Line 119:		Line 119:

	== References ==		== References ==
		+
		+	[[Category:How_To]]

← Older revision		Revision as of 08:31, 22 August 2015
Line 101:		Line 101:

	== Data mining ==		== Data mining ==
		+
		+	== Object encryption ==

	== Resources ==		== Resources ==

← Older revision		Revision as of 10:56, 15 July 2015
Line 101:		Line 101:

	== Data mining ==		== Data mining ==
		+
		+	== Resources ==
		+
		+	=== Environment ===
		+
		+	== Related ==
		+
		+	* [[Installing linux]]
		+	* [[Linux applications]]
		+	* [[Linux security]]
		+	* [[Kinky linux command-line]]
		+	* [[Anonymising your traffic with linux]]
		+	* [[Clean up all teh things]]
		+	* [[Encrypting everything]]
		+
		+	== References ==

← Older revision		Revision as of 15:18, 13 July 2015
Line 99:		Line 99:
	If named arpsweep (or arpsweep.sh) call with (for example):		If named arpsweep (or arpsweep.sh) call with (for example):
	$ arpsweep 192.168 eth0		$ arpsweep 192.168 eth0
		+
		+	== Data mining ==

@@ Line 15: / Line 15: @@
 == Environment ==
-== Testing ==
+== Mental shortcuts ==
-−
-=== Infinite loop ===
-−
-Sometimes we need a simple test script, a simple infinite loop, for example to illustrate process commands (see [[Kinky_linux_command-line#Changing_process_priority|Changing process priority]]).
 <pre>