Re: [gentoo-dev] [PATCH] eutils.eclass: Add awk wrapper - eawk - edit file in place

[Amadeusz Żołnowski]

"Robin H. Johnson" <robbat2@g.o> writes:
> 1.
> If your AWK command has an error, then this clobbers the file, a
> better variant, with die, would be:
> awk "$@" "$f" >"${tmpf}" || die "awk failed..."
> cp -f "${tmpf}" "$f" || die "copy back failed"

Thanks! On the one hand it's a simple function, and on the other hand
there are several things which can go wrong. I will submit corrected
version with unit test.

Why '-f' is required?


>> # @USAGE: <file> <args>
> This calling format is also a problem if they intended to pass multiple
> files to the command, or if they do so accidentally.
>
> Eg, an unprotected glob in the first argument, eg:
> eawk foo* '/foobar/{$1="x"; print $0}'
>
> If foo1 and foo2 existed, this would be considered as:
> awk foo2 /foobar/{$1="x"; print $0}' foo1
>
> which really will NOT have the desired effect.

I am aware of this. I considered before:

  a) eawk files... -- awk_args...
  b) eawk awk_args -- pattern files...

making '--' required, but that just complicates usage and function
itself. And anyway isn't it true for any other command with careless
glob use?

I have documented that function takes a file, not files. The effect of
misuse eawk would be awk error. Although maybe it would be useful to
support multiple files? Then I'd go for variant (b) probably.

Cheers,

-- 
Amadeusz Żołnowski