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From: Russ P. on 7 May 2010 00:30
On May 6, 6:57 pm, Ben Finney <ben+u...(a)benfinney.id.au> wrote:
> "Russ P." <russ.paie...(a)gmail.com> writes:
> > On May 6, 5:17 pm, Seebs <usenet-nos...(a)seebs.net> wrote:
> > > On 2010-05-07, Russ P. <russ.paie...(a)gmail.com> wrote:
> > > > In other words, I need to replace slash with dash in bash. It just
> > > > occurred to me that I am a poet and didn't even know it.
>
> > > $(echo "$foo" | tr / -)
>
> > > There's probably a bashism for this, but I wouldn't bother, usually.
>
> > Fabulous! Thanks.
>
> Be aware that this will impose the overhead of three extra processes for
> every such substitutiontransformation you want to do. That overhead may be
> acceptable for your use case, but you should still be aware of it.
>
> Doing it with a Bash parameter substitution will perform the
> substitution all in the same process (zero extra processes).

Either solution is perfectly fine for my problem, but yours gets the
nod for not requiring an outside program. I have read an entire book
on Bash and browsed the man page many times, but I never knew it had a
that character-substitution capability built in.

Russ P.
From: Teemu Likonen on 7 May 2010 07:12
* 2010-05-07 00:17 (UTC), Seebs wrote:

> On 2010-05-07, Russ P. <russ.paielli(a)gmail.com> wrote:
>> In other words, I need to replace slash with dash in bash. It just
>> occurred to me that I am a poet and didn't even know it.
>
> $(echo "$foo" | tr / -)

echo command may not be robust because it may interpret some part of
$foo as options. For example, this doesn't print anything:

string=-n
echo "$string"

Using printf or a "here string" is better:

printf '%s\n' "$string" | tr / -
tr / - <<< "$string"

But I actually suggest using Bash's ${string//\//-} form.
From: Ed Morton on 7 May 2010 07:35
On 5/6/2010 7:04 PM, Russ P. wrote:
> I am writing a bash script that needs to convert a directory name that
> is several levels deep to another directory name with no
> subdirectories. To do that, I will change all the slashes to dashes.
> Is there a simple way to do this in bash? Thanks.
>
> In other words, I need to replace slash with dash in bash. It just
> occurred to me that I am a poet and didn't even know it.
>
> Russ P.

$ foo="a/b/c"; echo "${foo//\//-}"
a-b-c

Ed.
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