Re: -format options

[Andrew Cagney <cagney@redhat.com>]

Chris Moller wrote:
> Any reason you couldn't just pass a kind of printf format string to
> -format.  E.g.,
>
>     print 1.0 "%g 0x%08x"
>
> would print the value first as a double--1.0--and then again in hex. 
> (Unlike printf, each % substitution would refer to the same value.)
>   
interesting idea; I'm not sure how well it will interact with more 
complex values for instance:

     (fhpd) print a_struct
     { i = 1, f = 1.0 }

and:

    (fhpd) print a_struct -format rx
    { i - 0x1, f = 0x3f800000 }

however a separate << printf <format> option list >> command might make 
for an interesting extension; for instance:

    (fhpd) printf "%x\n", a_struct
    0x1, 0x3f800000

i.e., apply a printf format to all elements of the value.

Andrew

PS: The fhpd outlines the command << print -format >>

> cm
>
>
> Andrew Cagney wrote:
>   
>> Hi,
>>
>> some questions, and ideas.
>>
>> What should the -format qualifier do when applied to floating point? 
>> For instance:
>>  (fhpd) print 1.0 -format x
>>  0x1
>> i.e., convert the cooked value to decimal and then print in hex; or:
>>  (fhpd) print 1.0 -format x
>>  0x3ff0000000000000
>> i.e., print the raw value in hex.  I think the answer depends on the
>> next question.
>>
>> What possible format options are there and how should they interact?
>> Here's a possible list:
>>  bi[t]s, [o]ctal, [d]ecimal, he[x]adecimal, [f]loat, [v]alue (i.e.,
>> default)
>>  [r]aw, [c]ooked
>>  [b]ig-endian, [l]ittle-endian, [n]ative (for default)
>>  [s]igned, [u]nsigned, [i]nteger (for default???)
>>  reset: -
>> are there others?  I've tried to make each set largely orthogonal;
>> does this work?  Would other combinations be better?  For
>> signed/unsigned is there a better "default" to integer.  Should
>> [o][x][t] just imply unsigned?
>>
>> How should these options be specified; Either:
>>    -format rx
>> or
>>    -format x -data r -order b
>> for dumping each field in big-endian raw hex.  I prefer the more terse
>> former.
>>
>>     
>
>