On 04/09/2021, ropers <rop...@gmail.com> wrote: > On 04/09/2021, Marc Chantreux <m...@unistra.fr> wrote: >> Another solution is to write commands for this kind of tasks: >> >> <<\. cat > ~/x >> #! /bin/ksh >> >> sed -r 's/a/&\ >> /g' >> . > > Wait, hold up, I'm not familiar with this input redirection idiom. > Could you explain? Why the double <, and why does it not work with a single > <? > Also, could you explain the escaped period?[0] This is very hard to > google.
I've realised the <<char redirection is a Here Document, which is very googleable. (Silly me. My excuse --that I'm sticking to-- is that the order and lack of whitespace also threw me, as I've more often seen this put thus: cat << HERE > ~/x) But I still don't understand why you escaped the dot. Is that just an overly cautious hypercorrection, or is there some reason I should escape periods in such cases? An unescaped full stop works fine for me. Ian
