This manual page is part of the POSIX Programmer's Manual. The Linux implementation of this interface

       If the type long contains more than 32 bits, the result of a64l(l64a(x)) is x in the low-order 32 bits.

       Portions of this text are reprinted and reproduced in electronic form from IEEE Std 1003.1-2017, Standard
       for Information  Technology  --  Portable  Operating  System  Interface  (POSIX),  The  Open  Group  Base
       Specifications  Issue  7, 2018 Edition, Copyright (C) 2018 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 .

       Any  typographical  or formatting errors that appear in this page are most likely to have been introduced
       during  the  conversion  of  the  source  files  to  man  page  format.  To  report  such   errors,   see
       https://www.kernel.org/doc/man-pages/reporting_bugs.html .

IEEE/The Open Group                                   2017                                          A64L(3POSIX)

       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 corresponding long value. If the string pointed to by s contains more
       than six characters, a64l() shall use the first six. If the first six characters 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 thread-safe.

       No errors are defined.

       Thefollowingsectionsareinformative.

       None.

       None.

       a64l, l64a — convert between a 32-bit integer and a radix-64 ASCII string

       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.

       This is not the same encoding as used by either encoding variant of the uuencode utility.

       Upon successful completion, a64l() shall return the long value resulting 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 representation. If value is 0L, l64a() shall
       return a pointer to an empty string.

strtoul()

       The Base Definitions volume of POSIX.1‐2017, <stdlib.h>

       The Shell and Utilities volume of POSIX.1‐2017, uuencode

       #include <stdlib.h>

       long a64l(const char *s);
       char *l64a(long value);