Originální popis anglicky:
a64l, l64a - convert between long and base-64
Návod, kniha: Linux Programmer's Manual
#include <stdlib.h>
long a64l(char *str64);
char *l64a(long value);
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 longs have 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/".
The value returned by
a64l() may be a pointer to a static buffer,
possibly overwritten by later calls.
The behaviour 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).
XPG 4.2, POSIX 1003.1-2001.
uuencode(1),
itoa(3),
strtoul(3)
