AWK - Revision history

Goldbolt at 17:36, 16 November 2023

2023-11-16T17:36:15Z

Goldbolt at 15:58, 24 February 2023

2023-02-24T15:58:46Z

Goldbolt: /* Using awk */

2019-12-18T19:10:09Z

‎Using awk

Goldbolt: /* Using awk */

2019-12-18T19:09:48Z

‎Using awk

Goldbolt: /* Using awk */

2019-12-18T19:09:05Z

‎Using awk

Goldbolt: /* Using awk */

2019-07-30T19:01:54Z

‎Using awk

Goldbolt: /* Using awk */

2019-04-16T19:22:14Z

‎Using awk

Goldbolt at 14:10, 12 February 2019

2019-02-12T14:10:29Z

Goldbolt: Created page with "The awk utility shall execute programs written in the awk programming language, which is specialized for textual data manipulation. An awk program is a sequence of patterns an..."

2019-01-15T12:55:08Z

Created page with "The awk utility shall execute programs written in the awk programming language, which is specialized for textual data manipulation. An awk program is a sequence of patterns an..."

New page

The awk utility shall execute programs written in the awk programming language, which is specialized for textual data manipulation. An awk program is a sequence of patterns and corresponding actions. When input is read that matches a pattern, the action associated with that pattern is carried out.

Input shall be interpreted as a sequence of records. By default, a record is a line, less its terminating <newline>, but this can be changed by using the RS built-in variable. Each record of input shall be matched in turn against each pattern in the program. For each pattern matched, the associated action shall be executed.

The awk utility shall interpret each input record as a sequence of fields where, by default, a field is a string of non-<blank> non-<newline> characters. This default <blank> and <newline> field delimiter can be changed by using the FS built-in variable or the −F sepstring option. The awk utility shall denote the first field in a record $1, the second $2, and so on. The symbol $0 shall refer to the entire record; setting any other field causes the re-evaluation of $0. Assigning to $0 shall reset the values of all other fields and the NF built-in variable.

=Using awk=
<strong>Remove duplicates from a file</strong>

awk '!a[$0]++'

Example:
cat filename.txt | awk '!a[$0]++' >> newfile.txt

@@ Line 14: / Line 14: @@
      cat filename.txt | awk '!a[$0]++' >> newfile.txt
-Print the second line in something. This can be piped | output or whatever.
+Print the second line in something. This can be piped.
      awk '{print $2}'
 This can substitute "foo" with "bar" within a file.

← Older revision		Revision as of 15:58, 24 February 2023
Line 1:		Line 1:
		+	{{DISPLAYTITLE:awk}}
	The awk utility shall execute programs written in the awk programming language, which is specialized for textual data manipulation. An awk program is a sequence of patterns and corresponding actions. When input is read that matches a pattern, the action associated with that pattern is carried out.		The awk utility shall execute programs written in the awk programming language, which is specialized for textual data manipulation. An awk program is a sequence of patterns and corresponding actions. When input is read that matches a pattern, the action associated with that pattern is carried out.

← Older revision		Revision as of 19:10, 18 December 2019
Line 26:		Line 26:
	Print only up until first instance of "." for output of ls and grep:		Print only up until first instance of "." for output of ls and grep:

−	ls /dir1/dir2/ \|grep us \|awk -F "." '{print $1}'	+	ls /dir1/dir2/ \| grep us \| awk -F "." '{print $1}'

← Older revision		Revision as of 19:09, 18 December 2019
Line 24:		Line 24:


−	Print only up until "." for output of ls:	+	Print only up until first instance of "." for output of ls and grep:

	ls /dir1/dir2/ \|grep us \|awk -F "." '{print $1}'		ls /dir1/dir2/ \|grep us \|awk -F "." '{print $1}'

← Older revision		Revision as of 19:09, 18 December 2019
Line 22:		Line 22:

	awk 'BEGIN { ORS=" " }; { print $2 }'		awk 'BEGIN { ORS=" " }; { print $2 }'
		+
		+
		+	Print only up until "." for output of ls:
		+
		+	ls /dir1/dir2/ \|grep us \|awk -F "." '{print $1}'

← Older revision		Revision as of 19:01, 30 July 2019
Line 18:		Line 18:
	This can substitute "foo" with "bar" within a file.		This can substitute "foo" with "bar" within a file.
	awk '{gsub(/foo/,"bar")}' FILENAME		awk '{gsub(/foo/,"bar")}' FILENAME
		+
		+	Print all new lines to one line with a space between each item:
		+
		+	awk 'BEGIN { ORS=" " }; { print $2 }'

@@ Line 6: / Line 6: @@
 =Using awk=
-<strong>Remove duplicates from a file</strong>
+Remove duplicates from a file
      awk '!a[$0]++'
@@ Line 13: / Line 13: @@
      cat filename.txt | awk '!a[$0]++' >> newfile.txt
-<strong>Print the second line in something. This can be piped | output or whatever.</strong>
+Print the second line in something. This can be piped | output or whatever.
      awk '{print $2}'

← Older revision		Revision as of 14:10, 12 February 2019
Line 12:		Line 12:
	Example:		Example:
	cat filename.txt \| awk '!a[$0]++' >> newfile.txt		cat filename.txt \| awk '!a[$0]++' >> newfile.txt
		+
		+	<strong>Print the second line in something. This can be piped \| output or whatever.</strong>
		+	awk '{print $2}'