Insert LineFeed into string? ( echo -e ) [ Solved ]

[potong]

technosaurus: printf can replace echo (and I think it's posix too):

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# string='a,b,c,d,e'
# echo -e "${string//,/\n}"
a
b
c
d
e
# printf "${string//,/\n}\n"
a
b
c
d
e

Of course you have to remember to add your own newline!
For those that like to work with arrays (non-posix?)

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# IFS=, read -ra array <<<"$string"
# for i in "${!array[@]}";do printf "\${array[$i]}=\"${array[$i]}\"\n";done
${array[0]}="a"
${array[1]}="b"
${array[2]}="c"
${array[3]}="d"
${array[4]}="e"
# new_string=$(IFS=$'\n';printf "${array[*]}")
# printf "$new_string\n"
a
b
c
d
e

Basically this uses the $IFS variable to split the string into an array. Then uses it again to combine back into a string

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# another_string=$(printf "%s" "${array[@]/%/\n}")
# printf "$another_string"
a
b
c
d
e

Another way to achieve the same ends is to append a newline to each element of an array and then print the each element of the array.
But beware there is a gotcha:

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# yet_another_string=$(IFS=;printf "${array[*]/%/\n}")
# printf "$yet_another_string"
a
b
c
d
e# printf "$yet_another_string"|od -acx
0000000   a  nl   b  nl   c  nl   d  nl   e nul
          a  \n   b  \n   c  \n   d  \n   e  \0
        0a61 0a62 0a63 0a64 0065
0000011

The first printf "$string" chomps the last newline!! So use:

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# yet_another_string=$(IFS=;printf "%s" "${array[*]/%/\n}")
# printf "$yet_another_string"|od -acx
0000000   a  nl   b  nl   c  nl   d  nl   e  nl
          a  \n   b  \n   c  \n   d  \n   e  \n
        0a61 0a62 0a63 0a64 0a65
0000012

HTH

Potong

[big_bass]

this adds a new line to every character in a string

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string="Vertical"
echo -n "string" | sed 's/./&@/g '| tr '@' '\n' 

you can pass the octal code number too but more difficult to remember but very powerful combined with this http://www.asciitable.com/

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string="Vertical"
echo -n "string" | sed 's/./&@/g '| tr '@' '\012' 

this removes the last space from the string

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string="Vertical"
echo -n "string" | sed 's/./&@/g; s/@$//' | tr '@' '\012'

Note that the "sed" command adds a '@' character after every character,
except at the end of the string.
The "tr" then replaces the '@' characters with newlines.
It also assumes the input text does not end with a newline,
which would cause an extra blank space to be added at the
bottom

*I got and use that snippet from imagemajick



if you play with octal codes you can do many cool things the
forum doesnt show the format of these but they work

string="Verticaltabs"
echo -n "string" | sed 's/./&@/g '| tr '@' '\013'

string="bigtabs"
echo -n "string" | sed 's/./&@/g '| tr '@' '\011'

Joe

[potong]

Nearly forgot!

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# yas=$(set a b c d e;printf "%s\n" "$@")
# printf "$yas\n"
a
b
c
d
e

For an array-like method good for functions.
Lastly... "%s\n" can be any kind of format you like, check it out here.

HTH

Potong

p.s. big_bass: if your using gnu sed

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# sed 's/,/\n/g' <<<"a,b,c,d,e"
a
b
c
d
e

works too!

[technosaurus]

yes with some shells it ($@) is the only way to get array-like behavior (busybox ash and hush included)

ex

#print $3 - $8
echo ${@:3:6}

#print last 5 vars
POS=$(($#-5))
echo ${@:$POS:5}

or here is a practice script that I wrote to implement tail
it changes the separator so that set will store each line as a separate variable (line 1 is $1 and last line is $#)

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#!/bin/ash

tail_help(){
echo "tail -[cnqv] files"
exit
}

[ $1 ] || tail_help

while ([ $# > 0 ]) do
	case $1 in
	-h|--help)tail_help;;
	--version)echo "tail v0.0";exit;;
	-c)BYTES=${2};shift;shift;;
	--bytes=*)BYTES=${1%=*};shift;;
	-n)LINES=${2};shift;shift;;
	--lines=*)LINES=${1%=*};shift;;
	-q|--quiet|--silent)QUIET=1;shift;;
	-v|--verbose)VERBOSE=1;shift;;
	#todo -f and -s
	*)[ -f ${1} ] && break || tail_help;;
	esac
done

#for -f while goes here
for FILE in $@; do
	HEADER="==> "$FILE" <=="
	[ ! $QUIET ] && [ $# -gt 1 ] || [ $VERBOSE ] && echo $HEADER
#	while read LINE || [ $LINE ] && echo $LINE && LINE=""; do echo $LINE; done <"${FILE}"
	A=`while read -r LINE; do echo $LINE; done <"${FILE}";echo $LINE`
	[ ${#A} -lt 1 ] && echo && continue
	if [ $BYTES ];then
		#for -f compare BYTES to new $#A - old $#A and print the lesser
		i=$((${#A}-$BYTES))
		echo "${A:$i:$BYTES}"
	else
		OLDIFS=$IFS
		IFS="
"
		set ${A}
		#for -f get size here and compare to last
		LINES=${LINES:-10}
		shift $(($#-$LINES))
		for LINE in $@; do
			echo "${LINE}"
		done
		IFS=$OLDIFS
	fi

done

you can do a lot with IFS, set and string manipulation without having to use anything external to the shell

[big_bass]

Potong

p.s. big_bass: if your using gnu sed
Code:
# sed 's/,/\n/g' <<<"a,b,c,d,e"
a
b
c
d
e
works too!

hey potong nice thanks and without commas needed to separate
like this even more compact code

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sed 's/./&\n/g' <<<"string" 

for every single character show the single character and a new line


Joe