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A64L(3P)                   POSIX Programmer's Manual                  A64L(3P)

PROLOG
       This  manual  page is part of the POSIX Programmer's Manual.  The Linux
       implementation of this interface may differ (consult the  corresponding
       Linux  manual page for details of Linux behavior), or the interface may
       not be implemented on Linux.
NAME
       a64l, l64a - convert between a 32-bit  integer  and  a  radix-64  ASCII
       string
SYNOPSIS
       #include <stdlib.h>
       long a64l(const char *s);
       char *l64a(long value);

DESCRIPTION
       These  functions  maintain numbers stored in radix-64 ASCII characters.
       This is a notation by which 32-bit integers can be represented by up to
       six characters; each character represents a digit in radix-64 notation.
       If the type long contains more than 32 bits, only the low-order 32 bits
       shall be used for these operations.
       The characters used to represent digits are '.' (dot) for 0, '/' for 1,
       '0' through '9' for [2,11],  'A'  through  'Z'  for  [12,37],  and  'a'
       through 'z' for [38,63].
       The  a64l() function shall take a pointer to a radix-64 representation,
       in which the first digit is the least significant, and return the  cor-
       responding long value. If the string pointed to by s contains more than
       six characters, a64l() shall use the first six. If the first six  char-
       acters  of  the string contain a null terminator, a64l() shall use only
       characters preceding the null terminator.  The  a64l()  function  shall
       scan the character string from left to right with the least significant
       digit on the left, decoding each character as a 6-bit radix-64  number.
       If  the  type  long  contains more than 32 bits, the resulting value is
       sign-extended. The behavior of a64l() is unspecified if  s  is  a  null
       pointer  or  the string pointed to by s was not generated by a previous
       call to l64a().
       The l64a() function shall take a long argument and return a pointer  to
       the  corresponding  radix-64 representation.  The behavior of l64a() is
       unspecified if value is negative.
       The value returned by l64a() may be a pointer  into  a  static  buffer.
       Subsequent calls to l64a() may overwrite the buffer.
       The  l64a()  function  need  not  be  reentrant. A function that is not
       required to be reentrant is not required to be thread-safe.
RETURN VALUE
       Upon successful completion, a64l() shall return the long value  result-
       ing from conversion of the input string. If a string pointed to by s is
       an empty string, a64l() shall return 0L.
       The l64a() function shall return a pointer to the radix-64  representa-
       tion.   If  value  is  0L,  l64a()  shall  return a pointer to an empty
       string.
ERRORS
       No errors are defined.
       The following sections are informative.
EXAMPLES
       None.
APPLICATION USAGE
       If  the  type  long  contains  more  than  32  bits,  the   result   of
       a64l(l64a(x)) is x in the low-order 32 bits.
RATIONALE
       This is not the same encoding as used by either encoding variant of the
       uuencode utility.
FUTURE DIRECTIONS
       None.
SEE ALSO
       strtoul(),  the  Base  Definitions  volume   of   IEEE Std 1003.1-2001,
       <stdlib.h>,  the  Shell  and  Utilities volume of IEEE Std 1003.1-2001,
       uuencode
COPYRIGHT
       Portions of this text are reprinted and reproduced in  electronic  form
       from IEEE Std 1003.1, 2003 Edition, Standard for Information Technology
       -- Portable Operating System Interface (POSIX),  The  Open  Group  Base
       Specifications  Issue  6,  Copyright  (C) 2001-2003 by the Institute of
       Electrical and Electronics Engineers, Inc and The Open  Group.  In  the
       event of any discrepancy between this version and the original IEEE and
       The Open Group Standard, the original IEEE and The Open Group  Standard
       is  the  referee document. The original Standard can be obtained online
       at http://www.opengroup.org/unix/online.html .

IEEE/The Open Group                  2003                             A64L(3P)