How can I read each line from a file into one variable for the last field, and another variable for the other fields?

Question

How can I read a line from a file into two variables: one variable for the last field, and the the other variable for the other fields?

For example, I have a file:

hello world! 10s
It is a good day. 4m
...

I would like to read each line into two variables: one variable contains the time interval at the end of the line, and the other variable contains the fields before it. I was wondering how to do it; this is as far as I have gotten:

while read line 
do
 ... # split $line into $message and $interval
 myprogram "$message" "$interval"
done < "$inputfile" 

• jesse_b: Will the interval ever contain white space?
• Tim: Thanks. The time interval will be used as argument to sleep. If sleep accepts an argument with a space within it, then yes; otherwise, no.
• Jeff Schaller: Obligatory unix.stackexchange.com/q/169716/117549
• Tim: @JeffSchaller Could you tell me how I should rewrite my while loop? I have looked at the link
• Jeff Schaller: It's apparent that reading into variables is not your final destination; there might be other/better ways to accomplish your goal, if we knew what it was.

Answer 1

As long as the interval contains no whitespace this should work:

#!/bin/bash
input=/path/to/input
while read -r line; do
 message=${line% *}
 interval=${line##* }
 echo "$message"
 sleep "$interval"
done < "$input"

${line% *} Will strip everything after the last space character

${line##* } Will strip everything before the last space character