Re: Improving maximum command line length detection (Was: Re: [PATCH] Removal of obsolete AmigaOS support)

[Gary V. Vaughan]

I seem to recall working on a SCO 433MP box running an old Ultrix which had a 
1k line limit with /bin/sh.  That is only 2 loop iterations less, and might 
save us grief later.

Peter O'Gorman wrote:
> +    # Make testring a little bigger before we do anything with it.
> +    # a 4K string should be a reasonable start.
> +    for p in 3 4 5 6 7 8 9 10 11 12 ; do

Why not use `i' here...

> +      testring=$testring$testring
> +    done
>      # If test is not a shell built-in, we'll probably end up computing a
>      # maximum length that is only half of the actual maximum length, but
>      # we can't tell.
> -    while (test "X"`$CONFIG_SHELL [$]0 --fallback-echo "X$testring" 
> 2>/dev/null` \
> -              = "XX$testring") >/dev/null 2>&1 &&
> -           new_result=`expr "X$testring" : ".*" 2>&1` &&
> -           lt_cv_sys_max_cmd_len=$new_result &&
> -           test $i != 17 # 1/2 MB should be enough
> +    while (test "X"`$CONFIG_SHELL [$]0 --fallback-echo "X$testring$testring" 
> 2>/dev/null` \
> +              = "XX$testring$testring") >/dev/null 2>&1 &&
> +           test $i != 6 # 1/2 MB should be enough

And revert to $i != 17 here, for readability?

>      do
>        i=`expr $i + 1`
>        testring=$testring$testring
>      done
> +    # Only check the string length outside the loop.
> +    new_result=`expr "X$testring" : ".*" 2>&1`
> +    lt_cv_sys_max_cmd_len=$new_result
>      testring=
>      # Add a significant safety factor because C++ compilers can tack on massive
>      # amounts of additional arguments before passing them to the linker.

Haven't tested it, but looks good to me.  If no-one reports a problem in the 
next couple of days, feel free to commit.

Don't forget a NEWS entry :-)

Cheers,
        Gary.
--
  ())_.  Gary V. Vaughan    gary@(lilith.warpmail.net|gnu.org)
  ( '/   Research Scientist http://www.oranda.demon.co.uk       ,_())____
  / )=   GNU Hacker         http://www.gnu.org/software/libtool  \'      `&
`(_~)_   Tech' Author       http://sources.redhat.com/autobook   =`---d__/