Re: Slightly OT: Perl question

From: John Ackermann N8UR (enigo@hospser.gr)
Date: Sun Mar 16 2003 - 00:54:18 EET

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    Thanks, Hamish. I don't know why it didn't work when I tried something
    similar to that before. I'll give it another go.

    73,
    John

    --On Sunday, March 16, 2003 09:46:04 +1100 Hamish Moffatt
    <qckv.czjat@hayabusa.org> wrote:

    > On Sat, Mar 15, 2003 at 02:24:47PM -0500, John Ackermann N8UR wrote:
    >> I need to:
    >>
    >> (a) test whether one bit of a byte is set or not (e..g, is bit 5 of
    >> $myvar a 1 or a 0);
    >>
    >> and
    >>
    >> (b) do a binary AND of two bytes (in other words, apply a bitmask).
    >
    > Binary AND is the "&" operator as in C. So
    >
    > $c = $a & $b;
    > $y = $x & 0xFF;
    >
    > etc achieves (b), and similarly for (a),
    >
    > if ($myvar & 0x20) {
    > ....
    > }
    >
    > or perhaps more readably:
    >
    > if ($myvar & (1 << 5)) {
    > ....
    > }
    >
    >
    > Hamish
    > --
    > Hamish Moffatt VK3SB <tfgmq@spectranet.com> <azn.cyupqiteo@sampo.fi>
    >
    >

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