php man page for hash_copy

HASH_COPY(3)								 1							      HASH_COPY(3)

hash_copy - Copy hashing context

SYNOPSIS
       resource hash_copy (resource  $context)

DESCRIPTION
PARAMETERS
	      o $context
		- Hashing context returned by hash_init(3).

RETURN VALUES
	Returns a copy of Hashing Context resource.

EXAMPLES
       Example #1

	      hash_copy(3) example

	      <?php
	      $context = hash_init("md5");
	      hash_update($context, "data");

	      /* copy context to be able to continue using it */
	      $copy_context = hash_copy($context);

	      echo hash_final($context), "
";

	      hash_update($copy_context, "data");
	      echo hash_final($copy_context), "
";
	      ?>

	      The above example will output:

	      8d777f385d3dfec8815d20f7496026dc
	      511ae0b1c13f95e5f08f1a0dd3da3d93

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