Read lines from File in Bash and parse words into variables for mailx parameters
I have a bash script which reads lines from a text file with 4 columns(no headers). The number of lines can be a maximum of 4 lines or less. The words in each line are separated by SPACE character.
[email protected] [email protected];[email protected] Sub1 MailBody1
[email protected] [email protected];[email protected] Sub2 MailBody2
[email protected] [email protected];[email protected] Sub3 MailBody3
[email protected] [email protected];[email protected] Sub4 MailBody4
Currently, I am parsing the file and after getting each line, I am storing each word in every line into a variable and calling mailx four times. Wondering if is there is an elegant awk/sed solution to the below mentioned logic.
- find total number of lines
- while
read $line, store each line in a variable - parse each line as
i=( $line1 ),j=( $line2 )etc - get values from each line as
${i[0]},${i[1]},${i[2]}and${i[3]}etc - call
mailx -s ${i[2]} -t ${i[1]} -r ${i[0]} < ${i[3]} - parse next line and call
mailx - do this until no more lines or max 4 lines have been reached
Do awk or sed provide an elegant solution to the above iterating/looping logic?
Answer
Give this a shot:
head -n 4 mail.txt | while read from to subject body; do
mailx -s "$subject" -t "$to" -r "$from" <<< "$body"
done
head -n 4reads up to four lines from your text file.readcan read multiple variables from one line, so we can use named variables for readability.<<<is probably what you want for the redirection, rather than<. Probably.