sed a gnu tool - Serbipunk/notes GitHub Wiki

https://www.gnu.org/software/sed/manual/sed.html

replace a word in a file

(base) baimr@haoda7:~/testfield/test_awk$ echo 'mia san mia! fc bayern' >> mia.txt
(base) baimr@haoda7:~/testfield/test_awk$ cat mia.txt
mia san mia! fc bayern
(base) baimr@haoda7:~/testfield/test_awk$ sed -i 's/mia/MIA/g' mia.txt
(base) baimr@haoda7:~/testfield/test_awk$ cat mia.txt
MIA san MIA! fc bayern

https://www.cyberciti.biz/faq/how-to-use-sed-to-find-and-replace-text-in-files-in-linux-unix-shell/