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Re: binary test and position?

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From:
ToddAndMargo via perl6-users
Date:
February 2, 2019 04:26
Subject:
Re: binary test and position?
Message ID:
c31bc6fb-223c-0419-e5fe-378b3b986e21@zoho.com
On 2/1/19 8:07 PM, ToddAndMargo via perl6-users wrote:
> On 2/1/19 8:03 PM, ToddAndMargo via perl6-users wrote:
>>  > On Fri, Feb 1, 2019 at 9:37 PM ToddAndMargo via perl6-users
>>  > <perl6-users@perl.org> wrote:
>>  >>
>>  >> On 2/1/19 7:22 PM, ToddAndMargo via perl6-users wrote:
>>  >>> Hi All,
>>  >>>
>>  >>> On a type Buf, what do I use to check for the
>>  >>> position of a byte pattern?
>>  >>>
>>  >>>
>>  >>> Many thanks,
>>  >>> -T
>>  >>
>>  >>
>>  >> Basically, what am I doing wrong here?
>>  >>
>>  >> $ p6 'my $handle=open("filever.exe", :bin, :ro); my Buf $b; $b=
>>  >> $handle.read(5); say $b; say $b[2..4];; if ( $b[2..4] eq 
>> 0x90,0x00,0x04
>>  >> ) {say "y";} else {say "n"}; $handle.close;'
>>  >> Buf[uint8]:0x<4D 5A 90 00 03>
>>  >> (144 0 3)
>>  >> y
>>  >>
>>  >>
>>  >> I am testing to see if the pattern 0x90 0x00 0x04 exists,
>>  >> which is does not.
>>
>>
>> On 2/1/19 7:57 PM, Brad Gilbert wrote:
>>> `eq` is string equality
>>> `==` is numeric equality
>>>
>>> a Buf is neither.
>>>
>>> You want `eqv` (equivalent)
>>>
>>>      $b[2..4] eqv (0x90,0x00,0x04)
>>>
>>
>> That was it.  Thank you!
>>
>> $ p6 'my $handle=open("filever.exe", :bin, :ro); my Buf $b; $b= 
>> $handle.read(5); say $b; if ( $b[2..4] eqv (0x90,0x00,0x03) ) {say 
>> "y";} else {say "n"}; $handle.close;'
>> Buf[uint8]:0x<4D 5A 90 00 03>
>> y
>>
>> $ p6 'my $handle=open("filever.exe", :bin, :ro); my Buf $b; $b= 
>> $handle.read(5); say $b; if ( $b[2..4] eqv (0x90,0x00,0x04) ) {say 
>> "y";} else {say "n"}; $handle.close;'
>> Buf[uint8]:0x<4D 5A 90 00 03>
>> n
> 
> 
> How do I find the position of a pattern in a Buf?

Need `pos` for Buf

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