Re: Avoid using grep in func_lalib_p

[Ralf Wildenhues]

Hi Olly,

* Olly Betts wrote on Thu, Apr 24, 2008 at 08:04:03AM CEST:
> I noticed that the sed and grep combination in func_lalib_p can be
> folded into a single use of sed.  I don't think this is likely to
> be a hot spot, but it's an easy fix.
> 
> I'm not an expert on sed portability but it doesn't seem to fall afoul
> of anything in the autoconf manual.

Two things: sed Q is nonportable, it's a GNU extension.

Also, proprietary seds typically don't barf with a script of 4q whatever
their input (binary, really long lines).  We don't like generating
needless core files.

So thanks for the patch, but no, unfortunately not acceptable.

Cheers,
Ralf

> --- a/libltdl/config/ltmain.m4sh
> +++ b/libltdl/config/ltmain.m4sh
> @@ -451,8 +451,8 @@ $opt_help || {
>  # determined imposters.
>  func_lalib_p ()
>  {
> -    $SED -e 4q "$1" 2>/dev/null \
> -      | $GREP "^# Generated by .*$PACKAGE" > /dev/null 2>&1
> +    lalip_p=`$SED "/^# Generated by .*$PACKAGE/q;4Q;d" "$1" 2> /dev/null`
> +    test -n "$lalip_p"
>  }
>  
>  # func_lalib_unsafe_p file