$ sed --version

sed (GNU sed) 4.7

Copyright (C) 2018 Free Software Foundation, Inc.

License GPLv3+: GNU GPL version 3 or later <https://gnu.org/licenses/gpl.html>.

This is free software: you are free to change and redistribute it.

There is NO WARRANTY, to the extent permitted by law.

Written by Jay Fenlason, Tom Lord, Ken Pizzini,

Paolo Bonzini, Jim Meyering, and Assaf Gordon.

GNU sed home page: <https://www.gnu.org/software/sed/>.

General help using GNU software: <https://www.gnu.org/gethelp/>.

E-mail bug reports to: <bug-sed@gnu.org>.

While '\t' matches a literal 't' when 't' is the delimiter, '\n' does not match 'n' when 'n' is the delimiter. See:

$ echo t | sed 'st\ttt' | xxd

00000000: 0a                                       .

$

$ echo n | sed 'sn\nnn' | xxd

00000000: 6e0a

Is this a bug or is there a sound logic behind this?

Oğuz