Description

   The a64l and l64a functions are used to maintain numbers stored
   in base-64 ASCII characters:

   o  a64l converts a character string to a long integer.

   o  l64a converts a long integer to a character string.

   Each character used to store a long integer represents a numeric
   value from 0 through 63. Up to six characters can be used to
   represent a long integer.

   The characters are translated as follows:

   o  A period (.)  represents 0.

   o  A slash (/)  represents 1.

   o  The numbers 0 through 9 represent 2 through 11.

   o  Uppercase letters A through Z represent 12 through 37.

   o  Lowercase letters a through z represent 38 through 63.

   The l64a function takes a long integer and returns a pointer to a
   corresponding base-64 notation of the least significant 32 bits.

   The value returned by l64a is a pointer to a thread-specific
   buffer whose contents are overwritten on subsequent calls from
   the same

   See also a64l.