CNT-2311-Chapter 4 Notes - Revision history

BenFranske: /* File Naming and Wildcard Expansion Rules */

2011-02-15T20:42:39Z

File Naming and Wildcard Expansion Rules

← Older revision		Revision as of 20:42, 15 February 2011
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	*?: Stands in for another single character		*?: Stands in for another single character

	**: Matches any character or any set of characters		<nowiki></nowiki>: Matches any character or any set of characters

	*[]: Normally match any character in a set. Also possible to specify a range of values		*[]: Normally match any character in a set. Also possible to specify a range of values

Moniquemoison at 20:30, 15 February 2011

2011-02-15T20:30:08Z

← Older revision		Revision as of 20:30, 15 February 2011
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	'''Three classes of wildcards'''		'''Three classes of wildcards'''

	*? Stands in for another single character		*?: Stands in for another single character

	** Matches any character or any set of characters		**: Matches any character or any set of characters

	*[] Normally match any character in a set. Also possible to specify a range of values		*[]: Normally match any character in a set. Also possible to specify a range of values

	== File Commands ==		== File Commands ==

Moniquemoison at 20:22, 15 February 2011

2011-02-15T20:22:38Z

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	tar: Stands for tape archiver. This utility is used to archive data to other media.		tar: Stands for tape archiver. This utility is used to archive data to other media.

	cpio: Used to restore data. ~~Has three~~ modes:		cpio: Used to restore data. There are 3 modes.
	*Copy-out mode: Creates an archive and copies files into it.		*Copy-out mode: Creates an archive and copies files into it.
	*Copy-in mode: Extracts data from an existing archive.		*Copy-in mode: Extracts data from an existing archive.
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	== Managing Links ==		== Managing Links ==

	~~The~~ ln ~~command is~~ used to create links.		ln: used to create links.

	There are two types of links:		There are two types of links:

Moniquemoison at 20:20, 15 February 2011

2011-02-15T20:20:12Z

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	Security is built on file ownership and file permission.		Security is built on file ownership and file permission.
			<br>
			Whenever a file is created it’s assigned an owner.

	ls-l : shows the permissions on a file		ls-l : shows the permissions on a file

	~~Whenever a file is created it’s assigned an owner~~

	chown: used to change a file's ownership and may only be used by root		chown: used to change a file's ownership and may only be used by root

Moniquemoison: Created page with "== File Naming and Wildcard Expansion Rules == Linux file names can contain uppercase/lowercase letters, numbers, and most punctuation and control characters. (.) Files refer to..."

2011-02-15T20:13:42Z

Created page with "== File Naming and Wildcard Expansion Rules == Linux file names can contain uppercase/lowercase letters, numbers, and most punctuation and control characters. (.) Files refer to..."

New page

== File Naming and Wildcard Expansion Rules ==
Linux file names can contain uppercase/lowercase letters, numbers, and most punctuation and control characters.

(.) Files refer to the current directory

(..) Files refer to the parent directory

File names are case-sensitive.

'''Three classes of wildcards'''

*? Stands in for another single character

** Matches any character or any set of characters

*[] Normally match any character in a set. Also possible to specify a range of values

== File Commands ==
ls: displays the names of files in a directory. Short for “list”.

cp: Copies a file.

mv: Move files and directories from one place to another and rename them.

rm: Remove command used to delete files.

touch: Modifies file time stamps.

'''Archiving Commands'''

tar: Stands for tape archiver. This utility is used to archive data to other media.

cpio: Used to restore data. Has three modes:
*Copy-out mode: Creates an archive and copies files into it.
*Copy-in mode: Extracts data from an existing archive.
*Copy-pass mode: Combines the copy-out and copy-in modes, enabling you to copy a directory from one location to another.

dd: Low level copying program normally useful with partitions.

'''Directory Commands'''

mkdir: Creates a directory

rmdir: Destroys a directory

== Managing Links ==

The ln command is used to create links.

There are two types of links:
*Hard links: create two directory entries that point to the same file.
*Soft links: Sometimes referred to as symbolic links. Soft links are a separate file whose content points to the linked-to file.

== Managing File Ownership ==

Security is built on file ownership and file permission.

ls-l : shows the permissions on a file

Whenever a file is created it’s assigned an owner

chown: used to change a file's ownership and may only be used by root

chgrp: change a file's group

'''Permission Bits'''

r: read

w: write

x: execute

X: execute only if the file is a directory or already has execute permission

s: SUID or SGID
*SUID: Set user id option used with executable files to run with permission of the owner of the file
*SGID: Set group ID. Sets the group of the running program to the group of the file.

t: sticky bit which is used to protect files from being deleted by those who don’t own the files

== File Locating Commands ==

find [path…] [expression…]
*Very flexible and likely to succeed
*Tends to be slow
*example of an expression is –name, used to match exact file names

locate ''search-string''
*Typically faster than find
*Only searches by file names
*Likely to return false alarms becuase any file containing the name that is searched for will come up

whereis
*Searches for files in a restricted set of locations
*Returns filenames that begin with what you type in

which
*Searches your path for what you type in
*Lists the path to first match it finds

type
*Tells you how a command you type will be interpreted
*It might say a command is a built-in, external, or alias command.