#stackoverflow #superuser #stackexchange

README.md

Replace multiline text with Bash

Here is a Bash script using ed line editor to replace / update a part of multiline text in a text file with automatically generated content (eg: Table of contents) 👇

replace.sh

#!/usr/bin/env bash
# -*- coding: UTF-8 -*-
#
# github   : https://github.com/JV-conseil
# www      : https://www.jv-conseil.net
# author   : JV-conseil
#===============================================
set -Eeou pipefail
shopt -s failglob

_lines=""

for i in {1..10}; do
  _lines+=$'\n'"${i}. ""$(openssl rand -hex 12)"
done

ed -s "./sample.md" <<EOF
/## BEGIN GENERATED/+,/## END GENERATED/-d
/## BEGIN GENERATED/a
${_lines}

.
wq
EOF

sample.md

# How to replace part of a text file between markers with another text file?

Here is a Bash script using [ed line editor](https://www.gnu.org/software/ed/manual/ed_manual.html "GNU manual for ed line editor") to replace / update a part of multiline text in a text file with
automatically generated content (eg: Table of contents) 👇

## BEGIN GENERATED

1. d5c10e45943b196b005771f1
2. bc56de530fbf5342d55203b4
3. 9608f31a09c2ece9c9cee4dd
4. 54e361257aecce0a937211c0
5. c4b2edf88293df0747694c37
6. a80275accc9b2bc72d55efcd
7. 3a2e2fec5da23b415569de00
8. 524655319a05e7dd1f48e6a5
9. 879d17e9e611d163e5a85b02
10. 80d311a786efcd9d01da86f6

## END GENERATED

Lorem ipsum dolor sit amet, consectetur adipiscing elit. Mauris et libero eu nunc
dapibus volutpat. Proin eu neque eu orci volutpat bibendum...

Read the answers on superuser.com • stackoverflow.com

replace.sh

#!/usr/bin/env bash
# -*- coding: UTF-8 -*-
#
# github   : https://github.com/JV-conseil
# www      : https://www.jv-conseil.net
# author   : JV-conseil
#===============================================
set -Eeou pipefail
shopt -s failglob

_lines=""

for i in {1..10}; do
  _lines+=$'\n'"${i}. ""$(openssl rand -hex 12)"
done

ed -s "./sample.md" <<EOF
/## BEGIN GENERATED/+,/## END GENERATED/-d
/## BEGIN GENERATED/a
${_lines}

.
wq
EOF

sample.md

How to replace part of a text file between markers with another text file?

Here is a Bash script using ed line editor to replace / update a part of multiline text in a text file with automatically generated content (eg: Table of contents) 👇

BEGIN GENERATED

1. d5c10e45943b196b005771f1
2. bc56de530fbf5342d55203b4
3. 9608f31a09c2ece9c9cee4dd
4. 54e361257aecce0a937211c0
5. c4b2edf88293df0747694c37
6. a80275accc9b2bc72d55efcd
7. 3a2e2fec5da23b415569de00
8. 524655319a05e7dd1f48e6a5
9. 879d17e9e611d163e5a85b02
10. 80d311a786efcd9d01da86f6

END GENERATED

Lorem ipsum dolor sit amet, consectetur adipiscing elit. Mauris et libero eu nunc dapibus volutpat. Proin eu neque eu orci volutpat bibendum...