Beefy Boxes and Bandwidth Generously Provided by pair Networks
The stupid question is the question not asked

comment on

( #3333=superdoc: print w/replies, xml ) Need Help??

Hello BrowserUk,

As I understand it, pack (A2)*, LIST says: for each element in LIST, convert it to a 2-byte ASCII string, padded with a trailing space character if necessary; then return the concatenation of these converted elements as a single string.

Logically, then, since unpack “does the reverse of pack”, unpack (A2)*, STRING should break STRING into 2-character chunks, and for each chunk, first remove any trailing spaces, then convert it to an appropriate value. Which is what I see:

2:03 >perl -MData::Dump -wE "my @c = unpack '(A2)*', 'f 12dx z'; dd \ +@c;" ["f", 12, "dx", " z"] 2:04 >

Note that "f " has been converted to "f" by removal of the trailing space (padding).

print unpack 'C*', pack '(Z2)*', 'fr','ed','x';; 102 0 101 0 120 0 ## Note! the 'r' & 'd' characters have been thrown +away? Another bug?

I don’t see a problem here, either. The template Z2 specifies a 2-byte null-terminated string. Packing 'fr' of course requires 3 bytes, so the second character is thrown away and the packed result is f\0. Isn’t that what it’s supposed to do?

Hope that helps (and I apologise if I’ve missed the point!),

Athanasius <°(((><contra mundum Iustus alius egestas vitae, eros Piratica,

In reply to Re: pack() v unpack() padding: bug or ??? by Athanasius
in thread pack() v unpack() padding: bug or ??? by BrowserUk

Use:  <p> text here (a paragraph) </p>
and:  <code> code here </code>
to format your post; it's "PerlMonks-approved HTML":

  • Are you posting in the right place? Check out Where do I post X? to know for sure.
  • Posts may use any of the Perl Monks Approved HTML tags. Currently these include the following:
    <code> <a> <b> <big> <blockquote> <br /> <dd> <dl> <dt> <em> <font> <h1> <h2> <h3> <h4> <h5> <h6> <hr /> <i> <li> <nbsp> <ol> <p> <small> <strike> <strong> <sub> <sup> <table> <td> <th> <tr> <tt> <u> <ul>
  • Snippets of code should be wrapped in <code> tags not <pre> tags. In fact, <pre> tags should generally be avoided. If they must be used, extreme care should be taken to ensure that their contents do not have long lines (<70 chars), in order to prevent horizontal scrolling (and possible janitor intervention).
  • Want more info? How to link or or How to display code and escape characters are good places to start.
Log In?

What's my password?
Create A New User
Domain Nodelet?
and the web crawler heard nothing...

How do I use this? | Other CB clients
Other Users?
Others cooling their heels in the Monastery: (4)
As of 2022-06-29 06:47 GMT
Find Nodes?
    Voting Booth?
    My most frequent journeys are powered by:

    Results (94 votes). Check out past polls.