Tab separated values in awk

Question

How do I select the first column from the TAB separated string?

# echo \"LOAD_SETTLED    LOAD_INIT       2011-01-13 03:50:01\" | awk -F\'\\t\' \'{print $1}\'         


        

Answer 1

Make sure they're really tabs! In bash, you can insert a tab using C-v TAB

$ echo "LOAD_SETTLED    LOAD_INIT       2011-01-13 03:50:01" | awk -F$'\t' '{print $1}'
LOAD_SETTLED

Answer 2

You need to set the OFS variable (output field separator) to be a tab:

echo "$line" | 
awk -v var="$mycol_new" -F $'\t' 'BEGIN {OFS = FS} {$3 = var; print}'

(make sure you quote the $line variable in the echo statement)

Answer 3

You can set the Field Separator:

... | awk 'BEGIN {FS="\t"}; {print $1}'

Excellent read:

https://docs.freebsd.org/info/gawk/gawk.info.Field_Separators.html

Answer 4

echo "LOAD_SETTLED    LOAD_INIT       2011-01-13 03:50:01" | awk -v var="test" 'BEGIN { FS = "[ \t]+" } ; { print $1 "\t" var "\t" $3 }'

Answer 5

Should this not work?

echo "LOAD_SETTLED    LOAD_INIT       2011-01-13 03:50:01" | awk '{print $1}'

Answer 6

Use:

awk -v FS='\t' -v OFS='\t' ...

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Example from one of my scripts.

I use the FS and OFS variables to manipulate BIND zone files, which are tab delimited:

awk -v FS='\t' -v OFS='\t' \
    -v record_type=$record_type \
    -v hostname=$hostname \
    -v ip_address=$ip_address '
$1==hostname && $3==record_type {$4=ip_address}
{print}
' $zone_file > $temp

This is a clean and easy to read way to do this.