This file has 3 fields. I wanted e.g. the first 2 fields in green, and the third in white (NB : black background), so I tried :
awk \'{print \"\\033[0;32m\"$
An alternative to using awk functions is passing the colors in shell variables. E.g.
RED='\033[01;31m'
GREEN='\033[01;32m'
YELLOW='\033[01;33m'
BLUE='\033[01;34m'
NONE='\033[0m'
echo "Col1 Col2 Col3 Col4" | \
awk -v r=$RED -v y=$YELLOW -v g=$GREEN -v b=$BLUE -v n=$NONE \
'{printf r$1n y$2n g$3n b$4n "\n"}'