Replace part of a string Shell Scripting

Question

I have lines and want to do sed operation, on string which comes after it has read '|'character three times. How can I do this in Shell Script?

Input: aaaa|bbbbb|ccccc|hello

Desired Ouput: aaaa|bbbbb|ccccc|hel

This is be done on hello which is after three '|'

-> sed 's/({.3}).*/\1/g'

Answer 1

You don't specify what you want to do with the last field to transform "hello" into "hel". Here's one way:

sed -r 's/^(([^|]+\|){3})(...).*/\1\3/' file

• ([^|]+\|) denotes a pipe delimited field (with the pipe)
• (([^|]+\|){3}) denotes three such fields
  • requires sed's -r option
  • on OSX or BSD-ish implementations of sed, use -E instead)
• I capture the next three characters with (...)
• then replace all with the first and third set of capturing parentheses

Answer 2

Use the cut command instead of sed:

$ echo "aaaa|bbbbb|ccccc|hello" | cut -d '|' -f 4
hello