a64l, l64a - convert between long and base-64


   #include <stdlib.h>

   long a64l(const char *str64);

   char *l64a(long value);

   Feature Test Macro Requirements for glibc (see feature_test_macros(7)):

   a64l(), l64a():
       _XOPEN_SOURCE >= 500
           || /* Glibc since 2.19: */ _DEFAULT_SOURCE
           || /* Glibc versions <= 2.19: */ _SVID_SOURCE


   These  functions  provide a conversion between 32-bit long integers and
   little-endian base-64 ASCII strings (of length zero to  six).   If  the
   string  used  as  argument for a64l() has length greater than six, only
   the first six bytes are used.  If the type long has more than 32  bits,
   then  l64a() uses only the low order 32 bits of value, and a64l() sign-
   extends its 32-bit result.

   The 64 digits in the base-64 system are:

          '.'  represents a 0
          '/'  represents a 1
          0-9  represent  2-11
          A-Z  represent 12-37
          a-z  represent 38-63

   So 123 = 59*64^0 + 1*64^1 = "v/".


   For  an  explanation  of  the  terms  used   in   this   section,   see

   Interface  Attribute      Value               
   l64a()     Thread safety  MT-Unsafe race:l64a 
   a64l()     Thread safety  MT-Safe             


   POSIX.1-2001, POSIX.1-2008.


   The  value  returned  by  l64a()  may  be a pointer to a static buffer,
   possibly overwritten by later calls.

   The behavior of l64a() is undefined when value is negative.   If  value
   is zero, it returns an empty string.

   These functions are broken in glibc before 2.2.5 (puts most significant
   digit first).

   This is not the encoding used by uuencode(1).


   uuencode(1), strtoul(3)


   This page is part of release 4.09 of the Linux  man-pages  project.   A
   description  of  the project, information about reporting bugs, and the
   latest    version    of    this    page,    can     be     found     at

                              2016-03-15                           A64L(3)


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