split variable into multiple variables in loop

Question

i am searching on these forums and trying different codes, but i cant seem to get it working:

i have a variable

ip="192.168.1.227 192.168.1.205 192.168.1.217" 

no i want to split every ip address up in to different variables

ip1=192.168.1.227 ip2=192.168.1.205 ip3=192.168.1.217 

i was trying to do something with word

for ((word in $vds; i=0; i++)); do echo $word "ip$i"=$word done 

but i cant get it working.

Answer 1

It is highly unlikely that you actually want separate variables for each individual IP number. It would be more manageable to store the IP numbers in an array.

ipnumbers=( $ip ) 

This unquoted use of $ip would (assuming the default value of the IFS variable) split its value on whitespaces (and invoke filename globbing on the resulting words, but that should not be an issue since there is no filename globbing patterns in the data). It would then assign the split up words as separate elements in the array ipnumbers.

You may then access the individual elements using e.g. "${ipnumbers[1]}" (for the second element), or loop over them with

for ipnum in "${ipnumbers[@]}"; do ...; done 

Answer 2

You will be better off by using an array variable.

 readarray -t -d ' ' ips <<<"$ip" 

This doesn't use the "unquoted" shell splitting that is usually problematic with newlines, glob characters (*, ?, []) and what not. Then just print the array:

 printf '%s\n' "${ips[@]}" 

Or use it in a loop:

for i in "${ips[@]}"; do echo "$i" done 

Answer 3

While the array clearly is the approach of choice, if you really really need the individual ip$number version, try

• eval your ip$i=$word assignment carefully looking at the quoting (with the precautions reg. the deprecated eval in mind)
• a small loop like for word in $ip; do read ip$((++CNT)) <<< $word; done