Concatenation of strings in bash

Question

I'm having issues with the following bash script trying to parse a version number from a WordPress readme file.

cat readme.txt | { while read -r a b c d; do if [ ${a} == "Stable" ] && [ ${b} == "tag:" ]; then VERSION="$c" fi done out="Updated to version $VERSION thanks" echo $out }

The output I expect is

Updated to version 1.15 thanks

but the actual output is

 thanks to version 1.15

as though the 'thanks' is replacing the front of the string, not being appended to the end. Any clues?

chepner · Accepted Answer · 2014-02-18 17:09:58Z

4

readme.txt and/or your script has DOS line endings; the value of VERSION has a trailing carriage return which affects the output.

answered Feb 18, 2014 at 17:09

chepner

538k77 gold badges594 silver badges746 bronze badges

Sign up to request clarification or add additional context in comments.

3 Comments

Barmar Over a year ago

It must be the file; if it were the script he would be getting syntax errors.

chepner Over a year ago

Ah, right. I couldn't see how $c could get a carriage return from the file, but that just requires a line with only 3 fields so that d isn't set.

user2985710 Over a year ago

Thanks modified code is VERSION=$(echo $c|tr -d '\n')

Martin Vidner · Accepted Answer · 2014-02-18 17:12:52Z

If you pipe the output to cat -A you will likely find out that $VERSION contains a carriage return.

You can get rid of the CRs with tr:

$ echo $'foo\rb' boo $ echo $'foo\rb' | tr -d '\r' foob

Collectives™ on Stack Overflow

Concatenation of strings in bash

2 Answers 2

3 Comments

Comments

Hot Network Questions

Collectives™ on Stack Overflow

2 Answers 2

3 Comments

Comments

Related