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

Andreas Schwab
2006-03-30T09:49:32Z

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, MaxfeldstraÃŸe 5, 90409 NÃ¼rnberg, Germany
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