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A64L(3)                  BSD Library Functions Manual                  A64L(3)

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

SYNOPSIS
     #include <stdlib.h>

     long
     a64l(const char *s);

     char *
     l64a(long value);

DESCRIPTION
     The a64l() and l64a() functions are used to 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 rep-resents represents
     resents a ``digit'' in a radix-64 notation.

     The characters used to represent digits are `.' 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 takes a pointer to a null-terminated radix-64 representation and returns a corre-sponding corresponding
     sponding 32-bit value.  If the string pointed to by s contains more than six characters, a64l() will
     use the first six.  a64l() scans the character string from left to right, decoding each character as a
     6-bit radix-64 number.  If a long integer is larger than 32 bits, the return value will be sign-extended. signextended.
     extended.

     l64a() takes a long integer argument value and returns a pointer to the corresponding radix-64 repre-sentation. representation.
     sentation.

RETURN VALUES
     On success, a64l() returns a 32-bit representation of s.  If s is a null pointer or if it contains dig-its digits
     its other than those described above.  a64l() returns -1 and sets the global variable errno to EINVAL.

     On success, l64a() returns a pointer to a string containing the radix-64 representation of value.  If
     value is 0, l64a() returns a pointer to the empty string.  If value is negative, l64a() returns a null
     pointer and sets the global variable errno to EINVAL.

WARNINGS
     The value returned by l64a() is a pointer into a static buffer, the contents of which will be overwrit-ten overwritten
     ten by subsequent calls.

     The value returned by a64l() may be incorrect if the value is too large; for that reason, only strings
     that resulted from a call to l64a() should be used to call a64l().

     If a long integer is larger than 32 bits, only the low-order 32 bits are used.

STANDARDS
     The a64l() and l64a() functions conform to X/Open Portability Guide Issue 4, Version 2 (``XPG4.2'').

BSD                             August 17, 1997                            BSD