INN_PATH_PROG_ENSURE and AC_PROG_*

[Russ Allbery]

Julien ÉLIE <julien at trigofacile.com> writes:

> I see that Autoconf recognizes:
>
> AC_PROG_AWK
>    Check for gawk, mawk, nawk, and awk, in that order, and set
>    output variable AWK to the first one that is found.  It tries
>    gawk first because that is reported to be the best implementation.
>
> AC_PROG_EGREP
>    Check whether $GREP -E works, or else look for the best available
>    egrep or gegrep that accepts the longest input lines possible.
>    Set the output variable EGREP to whatever is chosen.
>
> AC_PROG_SED
>    Set output variable SED to a Sed implementation that conforms to
>    Posix and does not have arbitrary length limits.  Report an error
>    if no acceptable Sed is found.  See Limitations of Usual Tools,
>    for more information about portability problems with Sed.
>
> Couldn't we use these three calls instead of INN_PATH_PROG_ENSURE?
> I think it is OK for AWK and EGREP but I have concerns for SED
> (configure might not set a value for it?).

The thing that INN_PATH_PROG_ENSURE does is fail with an error if the
program can't be found, and I don't think any of the above do.  However,
they do better checks for what we're checking for.

We could probably replace the current INN_PATH_PROG_ENSURE calls with
something that calls the above and then fails if the output variable
isn't set.  Although, in practice, I suppose it's horribly unlikely that
someone doesn't have an awk, egrep, or sed, so maybe it isn't worth
worrying that much about.

So yes, I think I agree.

-- 
Russ Allbery (rra at stanford.edu)             <http://www.eyrie.org/~eagle/>

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