/sys$common/syshlp/helplib.hlb FORTRAN, Intrinsic Procedures, BTEST  *Conan The Librarian (sorry for the slow response - running on an old VAX)

  BTEST (integer, position)

  A function that returns a logical value of true if the bit within
  the integer specified by position is set to 1.  The low-order bit
  is position 0.

  +------+---------+----------+------------+-------------+
  | Args | Generic | Specific |  Argument  | Result Type |
  +------+---------+----------+------------+-------------+
  |   2  |  BTEST  | BITEST   | INTEGER*2  | INTEGER*2   |
  |      |         | BJTEST   | INTEGER*4  | INTEGER*4   |
  +------+---------+----------+------------+-------------+