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string, or integer?

by Ryszard (Priest)
on May 10, 2004 at 14:57 UTC ( #352089=perlquestion: print w/replies, xml ) Need Help??

Ryszard has asked for the wisdom of the Perl Monks concerning the following question:

Its the end of a very long day, and i'm a bit stuck.

I need to send two bytes to a daemon to let it know the message length, the bytes have to bytes and not an ascii representation of bytes.

For example, I want 00001001, not 00111001.

unpack("B*", int(length($msg)/256)) yeilds the latter, not the former, how do I force the case?


Replies are listed 'Best First'.
Re: string, or integer?
by halley (Prior) on May 10, 2004 at 15:02 UTC
    You should have guessed that pack() is the opposite of unpack(). From perldoc -f pack:
      The resulting string is the concatenation of the converted values. Typically, each converted value looks like its machine-level representation.
    my $bytes = pack("n", 9); # network byte order for 0x0009

    [ e d @ h a l l e y . c c ]

Re: string, or integer?
by dave_the_m (Monsignor) on May 10, 2004 at 15:05 UTC
    pack 'n', length($msg)
    (Replace n with N or S or whatever depending on what order (if any) you need the two bytes in

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