ifs – Tarik Billa

What does IFS= do in this bash loop: `cat file | while IFS= read -r line; do … done`

March 20, 2023 by Tarik

IFS does many things but you are asking about that particular loop. The effect in that loop is to preserve leading and trailing white space in line. To illustrate, first observe with IFS set to nothing: $ echo ” this is a test ” | while IFS= read -r line; do echo “=$line=” ; done … Read more

What is the exact meaning of IFS=$’\n’?

December 12, 2022 by Tarik

Normally bash doesn’t interpret escape sequences in string literals. So if you write \n or “\n” or ‘\n’, that’s not a linebreak – it’s the letter n (in the first case) or a backslash followed by the letter n (in the other two cases). $’somestring’ is a syntax for string literals with escape sequences. So … Read more