On 2026-04-17 10:17, Laurent Lyaudet wrote:
Similarly "\s" could be required to match "\s" instead of spaces.
Yes, a non-GNU implementation could do that. POSIX allows this as well.
My current understanding is that '\' followed by another character is valid as a possible extension, since the literals "\x" may be matched with "\\x".
Yes, so long as it's not a BRE like '\*' where POSIX already specifies the behavior.
Are there other strings than '\' followed by another character that can be used as extensions, please?
Anything that's doesn't conform to the POSIX grammar for BREs can be used as an extension, unless the POSIX spec says it's invalid.
