On 6/23/10 4:54 AM, Yves wrote:
> Description:
> I want to generate a "bash-proof" string by enclosing it in
> single quotes and managing enclosed single quotes. Basically, I
> would replace << word1 word'2 >> with << 'word1 word'"'"'2' >>.
> I can't find the syntax for doing this with the ${p//x/y}
> substitution (see example below).
> Actually, command #4 /does/ produce the right substitution, but
> as soon as I enclose it in double quotes, extra double-quotes
> appear, and I can't see the logic behind it, nor the logic
> behind my further tests' results.
When bash encounters a double quote inside a double-quoted parameter
expansion, it opens a new quoting context. That's why the single quote
doesn't act as a special character. However, bash doesn't remove the
inner double quotes, because they're not one of the characters that's
special within double quotes. The latter is arguably a bug, but it's the
way bash has behaved for a long time.
Chet
--
``The lyf so short, the craft so long to lerne.'' - Chaucer
``Ars longa, vita brevis'' - Hippocrates
Chet Ramey, ITS, CWRU c...@case.edu http://cnswww.cns.cwru.edu/~chet/
