Why does my awk command adds the string to the beginning instead of appending at last

Question

I am trying to put a char at the end of each line in a file:

a
aa
aaa
aah
aahed
aahing
aahs
aal
aalii
aaliis

using sed/awk:

awk '{print  $0 "A"}' words_alpha.txt > words_alpha_hyp.txt
sed -i 's/$/A/' words_alpha.txt > words_alpha_hyp.txt

I got always instead the char 'a' a prefix:

 A
 A
 Aa
 Ah
 Ahed
 Ahing
 Ahs
 Al
 Alii
 Aliis
 Als
 Am
 Ani
 Ardvark
 Ardvarks

Interestingly if I try to '\n' before the char 'a':

awk '{print $0 "\n a"}' words_alpha.txt > words_alpha_hyp.txt

a
 a
aa
 a
aaa
 a
aah
 a
aahed
 a
aahing
 a
aahs
 a
aal
 a

I does what it supposed to do... I don't understand it...

Please add sample input (no descriptions, no images, no links) and your desired output for that sample input to your question (no comment). — Cyrus, Mar 06 '20 at 20:41

Inian · Accepted Answer · 2020-03-06T20:46:58.583

1

Your input file most likely has DOS CRLF line terminators i.e. instead of \n being a \r\n. Modify your record separator to handle those lines, needs GNU awk for having to use a multi character record separator

awk -v RS="\r\n" '{ $0 = $0 "a" }1' file

Or make the obvious choice of converting the file to *nix line endings \n by doing dos2unix file and run your original command again.

edited Mar 06 '20 at 20:46

answered Mar 06 '20 at 20:44

Inian

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2

You should mention that requires GNU awk for multi-char RS. – Ed Morton Mar 06 '20 at 20:45
1

Thanks. @EdMorton I do I agree the answer was in the post you cite but it could not be found with my search – asasa178 Mar 06 '20 at 20:55

Why does my awk command adds the string to the beginning instead of appending at last

1 Answers1