vec
vec - test or set particular bits in a string
vec EXPR,OFFSET,BITS
Treats a string as a vector of unsigned integers, and returns the value
of the bitfield specified. May also be assigned to. BITS must be a
power of two from 1 to 32.
Vectors created with
vec()
can also be manipulated with the logical
operators |, & and ^, which will assume a bit vector operation is
desired when both operands are strings.
To transform a bit vector into a string or array of 0's and 1's, use these:
<![CDATA[
$bits = unpack("b*", $vector);
@bits = split(//, unpack("b*", $vector));
]]>
If you know the exact length in bits, it can be used in place of the *.