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Re: [patch] Compile fix for 64-bit HPUX


Daniel Jacobowitz <drow@false.org> writes:

> On Wed, Mar 29, 2006 at 01:13:15AM +0200, Andreas Schwab wrote:
>> Daniel Jacobowitz <drow@false.org> writes:
>> 
>> >> +    oldcflags="${CFLAGS-}"
>> >
>> > What's ${foo-}?  I don't see it in my bash or dash docs.
>> 
>> In (bash)Shell Parameter Expansion, the paragraph before the table:
>> 
>>        When not performing substring expansion, Bash tests for a parameter
>>     that is unset or null; omitting the colon results in a test only for a
>>                            ^^^^^^^^^^^^^^^^^^
>>     parameter that is unset.
>
> Thanks.  I see this in the dash documentation too, and pdksh, so it is
> presumably portable.

The autoconf manual says:

`${VAR:-VALUE}'
     Old BSD shells, including the Ultrix `sh', don't accept the colon
     for any shell substitution, and complain and die.

Thus in fact, omitting the colon is more portable.

Andreas.

-- 
Andreas Schwab, SuSE Labs, schwab@suse.de
SuSE Linux Products GmbH, Maxfeldstraße 5, 90409 Nürnberg, Germany
PGP key fingerprint = 58CA 54C7 6D53 942B 1756  01D3 44D5 214B 8276 4ED5
"And now for something completely different."


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