Re: [9fans] what features would you like in a shell?

[sqweek <sqweek@gmail.com>]

2009/4/1 erik quanstrom <quanstro@quanstro.net>:
>> I've not run into many actual problems with rc so it's pretty near
>> perfect :>
>
> pretty near.
>
> redirection has a few rough points.  dealing with a device
> that expects a write then a read like /net/dns is painful.
> i can never get the syntax right the first try.
> and (hopefully this isn't just my ignorance) i don't know how
> to open a fd to a background shell as one would in bourne.

 I haven't sat down and understood the finer points of rc's
redirection yet, but the precedence relationships between > < and |
certainly confuse the hell out of me, coming from bourne ;)

 I'd like to see a shell that, when confronted with a pipeline that
looks like "<foo ... | ... >foo", realises input and output are headed
for the same file, and does whatever it needs to do to avoid
clobbering the file before reading it.

 re not reinventing the wheel, you might want to look into the es
shell. I think this is what erik alluded to earlier - I've never used
it myself but I understand it is extremely programmable, to the point
where you can redefine the pipe operator for example.
-sqweek