l64a(3) - c7

1A64L(3)                    Linux Programmer's Manual                   A64L(3)
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NAME

6       a64l, l64a - convert between long and base-64
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SYNOPSIS

9       #include <stdlib.h>
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11       long a64l(char *str64);
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13       char *l64a(long value);
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15   Feature Test Macro Requirements for glibc (see feature_test_macros(7)):
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17       a64l(), l64a():
18           _SVID_SOURCE || _XOPEN_SOURCE >= 500 ||
19           _XOPEN_SOURCE && _XOPEN_SOURCE_EXTENDED
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DESCRIPTION

22       These functions provide a conversion between 32-bit long  integers  and
23       little-endian  base-64  ASCII  strings (of length zero to six).  If the
24       string used as argument for a64l() has length greater  than  six,  only
25       the  first six bytes are used.  If the type long has more than 32 bits,
26       then l64a() uses only the low order 32 bits of value, and a64l()  sign-
27       extends its 32-bit result.
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29       The 64 digits in the base-64 system are:
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31              '.'  represents a 0
32              '/'  represents a 1
33              0-9  represent  2-11
34              A-Z  represent 12-37
35              a-z  represent 38-63
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37       So 123 = 59*64^0 + 1*64^1 = "v/".
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ATTRIBUTES

40   Multithreading (see pthreads(7))
41       The l64a() function is not thread-safe.
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43       The a64l() function is thread-safe.
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CONFORMING TO

46       POSIX.1-2001.
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NOTES

49       The  value returned by l64a() may be a pointer to a static buffer, pos‐
50       sibly overwritten by later calls.
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52       The behavior of l64a() is undefined when value is negative.   If  value
53       is zero, it returns an empty string.
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55       These functions are broken in glibc before 2.2.5 (puts most significant
56       digit first).
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58       This is not the encoding used by uuencode(1).
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COLOPHON

64       This page is part of release 3.53 of the Linux  man-pages  project.   A
65       description  of  the project, and information about reporting bugs, can
66       be found at http://www.kernel.org/doc/man-pages/.
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70                                  2013-06-21                           A64L(3)