awk one-liners

I have previously plugged the great list of sed 1-liners at http://sed.sourceforge.net/sed1line.txt.

Here is a similar (if shorter) list of handy awk 1-liners:

http://www.sap-basis-abap.com/unix/awk-one-liner-tips.htm:

Print column1, column5 and column7 of a data file or output of any columns list

awk '{print $1, $5, $7}' data_file

cat file_name |awk '{print $1 $5 $7}'

ls –al |awk '{print $1, $5, $7}' -- Prints file_permissions,size and date

List all files names whose file size greater than zero.

ls –al |awk '$5 > 0 {print $9}'

List all files whose file size equal to 512bytes.

ls –al |awk '$5 == 512 {print $9}'

print all lines

awk '{print }' file_name

awk '{print 0}' file_name

Number of lines in a file


awk ' END {print NR}' file_name

Number of columns in each row of a file

awk '{print NF}' file_name

Sort the output of file and eliminate duplicate rows

awk '{print $1, $5, $7}' |sort –u

List all file names whose file size is greater than 512bytes and owner is "oracle"

ls –al |awk '$3 == "oracle" && $5 > 512 {print $9}'

List all file names whose owner could be either "oracle" or "root"

ls –al |awk '$3 == "oracle" || $3 == "root" {print $9}'

list all the files whose owner is not "oracle

ls –al |awk '$3 != "oracle" {print $9}'

List all lines which has at least one or more characters

awk 'NF > 0 {print }' file_name

List all lines longer that 50 characters

awk 'length($0) > 50 {print }' file_name

List first two columns

awk '{print $1, $2}' file_name

Swap first two columns of a file and print

awk '{temp = $1; $1 = $2; $2 = temp; print }' file_name

Replace first column as "ORACLE" in a data file

awk '{$1 = "ORACLE"; print }' data_file

Remove first column values in a data file

awk '{$1 =""; print }' data_file

Calculate total size of a directory in Mb

ls –al |awk '{total +=$5};END {print "Total size: " total/1024/1024 " Mb"}'

Calculate total size of a directory including sub directories in Mb

ls –lR |awk '{total +=$5};END {print "Total size: " total/1024/1024 " Mb"}'


Find largest file in a directory including sub directories

ls –lR |awk '{print $5 "\t" $9}' |sort –n |tail -1

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8 Responses to awk one-liners

  1. Paul Mohr says:

    It is very interesting stuff. I ran into something very odd while trying out your examples. It seems that the CSS for section code uses a font-family Courier New. What is odd is that all my browsers display right slanting single quotes with a different font in the CSS code{} section. (gotta love Firebug) With the font that is selected there, I get some left slanting quotes. The issue, as you surely know, is that left slanters have a very different meaning in the shell. Nice blog, thank you for the information.

  2. unixshell says:

    You are right; I hadn’t noticed that, thanks. I’ll fix it.

  3. unixshell says:

    I’ve also removed the leading “$” symbols, for better copy/paste

  4. fmpdmb says:

    Minor corrections:

    List all files names whose file size greater than zero.

    ls –al |awk ‘$5 > 0 {print $8}’

    List all files whose file size equal to 512bytes.

    ls –al |awk ‘$5 == 512 {print $8}’

  5. Andrew says:

    Excellent list of awk commands. This is inspiring for a beginner like myself.

  6. kcoder24 says:

    Hi, good collection of one-liners. Eric Pement has already awk1line.txt and Peteris Krumis explain them in a very detailed way. So take a look here
    http://www.catonmat.net/series/awk-one-liners-explained
    An easy tip, the default action for a pattern is print $0, so you can make shorter several one-liners, e.g. for print all lines
    awk ‘{print 0}’ file_name ==> awk ’1′ file_name

  7. anusha says:

    very very Thanks.these examples are really helpful to me

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