Sed - Revision history

Franks at 04:48, 14 August 2008

2008-08-14T04:48:16Z

← Older revision		Revision as of 21:48, 13 August 2008
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	Sed stands for stream editor and it does just that, it edits a stream of text. There is many uses for it, for example in the well known substitution mode. Sometimes [[tr]] does a job better than sed.		Sed stands for stream editor and it does just that, it edits a stream of text. There is many uses for it, for example in the well known substitution mode. Sometimes [[tr]] does a job better than sed.

	== ~~sed and~~ substitution ==		== substitution ==

	Using the s allows the results to be substituted like so:		Using the s allows the results to be substituted like so:
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	ls *save\| while read i ; do NEW=`echo $i \| sed -e 's/-save//g'`; mv -f $i $NEW; done		ls *save\| while read i ; do NEW=`echo $i \| sed -e 's/-save//g'`; mv -f $i $NEW; done

	== ~~sed and~~ deleting ==		== deleting ==

	If I wanted to delete lines 1 through 46:		If I wanted to delete lines 1 through 46:
Line 27:		Line 27:
	You see the last two entries of a 48 line file. This can also be achieved with [[head]].		You see the last two entries of a 48 line file. This can also be achieved with [[head]].

	== ~~sed and printing~~ certain rows ==		== displaying certain rows ==

	To see the first entry in the /etc/passwd file:		To see the first entry in the /etc/passwd file:
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	smmsp:*:25:25:Sendmail Message Submission Program:/nonexistent:/sbin/nologin		smmsp:*:25:25:Sendmail Message Submission Program:/nonexistent:/sbin/nologin

	== ~~sed~~ delimiters ==		== delimiters ==

	pretend you see this:		pretend you see this:

Franks at 04:47, 14 August 2008

2008-08-14T04:47:44Z

← Older revision		Revision as of 21:47, 13 August 2008
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	== Introduction ==		== Introduction ==

	Sed stands for stream editor and it does just that, it edits a stream. There is many uses for it for example in the well known substitution mode. Sometimes [[tr]] does a job better than sed.		Sed stands for stream editor and it does just that, it edits a stream of text. There is many uses for it, for example in the well known substitution mode. Sometimes [[tr]] does a job better than sed.

	== sed and substitution ==		== sed and substitution ==
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	== sed and deleting ==		== sed and deleting ==

	If I wanted to delete lines 1 through 46 ~~the syntax would be so~~:		If I wanted to delete lines 1 through 46:

	francisco$ sed -e '1,46d' /etc/passwd		francisco$ sed -e '1,46d' /etc/passwd
Line 29:		Line 29:
	== sed and printing certain rows ==		== sed and printing certain rows ==

	~~Pretend you need to work on~~ the first entry in the /etc/passwd file:		To see the first entry in the /etc/passwd file:

	francisco$ sed -n 1p /etc/passwd		francisco$ sed -n 1p /etc/passwd
	root:*:0:0:Charlie &:/root:/bin/ksh		root:*:0:0:Charlie &:/root:/bin/ksh

	And this is how you ~~print~~ rows 2 through 5:		And this is how you display rows 2 through 5:

	francisco$ sed -n 2,5p /etc/passwd		francisco$ sed -n 2,5p /etc/passwd

Pbug: /* Introduction */ tr

2008-08-09T22:28:04Z

Introduction: tr

← Older revision		Revision as of 15:28, 9 August 2008
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	== Introduction ==		== Introduction ==

	Sed stands for stream editor and it does just that, it edits a stream. There is many uses for it for example in the well known substitution mode.		Sed stands for stream editor and it does just that, it edits a stream. There is many uses for it for example in the well known substitution mode. Sometimes [[tr]] does a job better than sed.


	== sed and substitution ==		== sed and substitution ==

Pbug: /* sed and printing certain rows */

2008-07-30T13:00:37Z

sed and printing certain rows

← Older revision		Revision as of 06:00, 30 July 2008
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	root:*:0:0:Charlie &:/root:/bin/ksh		root:*:0:0:Charlie &:/root:/bin/ksh

			And this is how you print rows 2 through 5:

			francisco$ sed -n 2,5p /etc/passwd
			daemon:*:1:1:The devil himself:/root:/sbin/nologin
			operator:*:2:5:System &:/operator:/sbin/nologin
			bin:*:3:7:Binaries Commands and Source,,,:/:/sbin/nologin
			smmsp:*:25:25:Sendmail Message Submission Program:/nonexistent:/sbin/nologin

	== sed delimiters ==		== sed delimiters ==

Pbug: /* sed and deleting */

2008-07-03T16:55:01Z

sed and deleting

← Older revision		Revision as of 09:55, 3 July 2008
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	testuser:*:1001:1001:test:/usr/home/testuser:/bin/ksh		testuser:*:1001:1001:test:/usr/home/testuser:/bin/ksh

	You see the last two entries of a 48 line file.		You see the last two entries of a 48 line file. This can also be achieved with [[head]].

	== sed and printing certain rows ==		== sed and printing certain rows ==

Pbug: /* sed and substitution */

2008-07-03T16:35:17Z

sed and substitution

← Older revision		Revision as of 09:35, 3 July 2008
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	bleep two three four bleep six seven eight nine		bleep two three four bleep six seven eight nine

			In a directory where files were backed up as "file-save" the renaming from the backup to the original file went like this:

			ls *save\| while read i ; do NEW=`echo $i \| sed -e 's/-save//g'`; mv -f $i $NEW; done

	== sed and deleting ==		== sed and deleting ==

Pbug: /* sed delimiters */

2008-07-02T14:26:48Z

sed delimiters

← Older revision		Revision as of 07:26, 2 July 2008
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	sed -e 's=rat=/raven/=g' file		sed -e 's=rat=/raven/=g' file

	it looks difficult because you may ~~know~~ know that sed can use any delimiter between a substitute.		it looks difficult because you may not know that sed can use any delimiter between a substitute.

	In the example given every instance of rat is changed to /raven/ with the slashes. Here is		In the example given every instance of rat is changed to /raven/ with the slashes. Here is

Pbug at 14:25, 2 July 2008

2008-07-02T14:25:46Z

← Older revision		Revision as of 07:25, 2 July 2008
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	francisco$ sed -n 1p /etc/passwd		francisco$ sed -n 1p /etc/passwd
	root:*:0:0:Charlie &:/root:/bin/ksh		root:*:0:0:Charlie &:/root:/bin/ksh


			== sed delimiters ==

			pretend you see this:

			sed -e 's=rat=/raven/=g' file

			it looks difficult because you may know know that sed can use any delimiter between a substitute.

			In the example given every instance of rat is changed to /raven/ with the slashes. Here is
			another one
			sed -e s,/bin,/newbin,g file

			Here the delimiter is a comma (,) and / is part of the substitute text. This is totally ok.

Pbug at 12:05, 2 July 2008

2008-07-02T12:05:17Z

← Older revision		Revision as of 05:05, 2 July 2008
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	You see the last two entries of a 48 line file.		You see the last two entries of a 48 line file.

			== sed and printing certain rows ==

			Pretend you need to work on the first entry in the /etc/passwd file:

			francisco$ sed -n 1p /etc/passwd
			root:*:0:0:Charlie &:/root:/bin/ksh

Pbug: New page: == Introduction == Sed stands for stream editor and it does just that, it edits a stream. There is many uses for it for example in the well known substitution mode. == sed and substitu...

2008-07-02T12:03:57Z

New page: == Introduction == Sed stands for stream editor and it does just that, it edits a stream. There is many uses for it for example in the well known substitution mode. == sed and substitu...

New page

== Introduction ==

Sed stands for stream editor and it does just that, it edits a stream. There is many uses for it for example in the well known substitution mode.

== sed and substitution ==

Using the s allows the results to be substituted like so:

echo one two three four five six seven eight nine | sed -e 's/one/bleep/g' -e 's/five/bleep/g'

would result in:

bleep two three four bleep six seven eight nine

== sed and deleting ==

If I wanted to delete lines 1 through 46 the syntax would be so:

francisco$ sed -e '1,46d' /etc/passwd
_postfix:*:507:507:Postfix Daemon:/var/empty:/sbin/nologin
testuser:*:1001:1001:test:/usr/home/testuser:/bin/ksh

You see the last two entries of a 48 line file.