A64L(3)                FreeBSD Library Functions Manual                A64L(3)

NAME
     a64l, l64a, l64a_r - convert between a long integer and a base-64 ASCII
     string

LIBRARY
     Standard C Library (libc, -lc)

SYNOPSIS
     #include <stdlib.h>

     long
     a64l(const char *s);

     char *
     l64a(long int l);

     int
     l64a_r(long int l, char *buffer, int buflen);

DESCRIPTION
     These 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 represents a digit in
     radix-64 notation.  If the type long contains more than 32 bits, only the
     low-order 32 bits are used for these operations.

     The characters used to represent "digits" are `.' for 0, `/' for 1, `0' -
     `9' for 2 - 11, `A' - `Z' for 12 - 37, and `a' - `z' for 38 - 63.

     The a64l() function takes a pointer to a radix-64 representation, in
     which the first digit is the least significant, and returns a
     corresponding long value.  If the string pointed to by s contains more
     than six characters, a64l() uses the first six.  If the first six
     characters of the string contain a null terminator, a64l() uses only
     characters preceding the null terminator.  The a64l() function scans 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 takes a long argument and returns a pointer to the
     corresponding radix-64 representation.  The behavior of l64a() is
     unspecified if value is negative.

     The value returned by l64a() is a pointer into a static buffer.
     Subsequent calls to l64a() may overwrite the buffer.

     The l64a_r() function performs a conversion identical to that of l64a()
     and stores the resulting representation in the memory area pointed to by
     buffer, consuming at most buflen characters including the terminating NUL
     character.

RETURN VALUES
     On successful completion, a64l() returns the long value resulting from
     conversion of the input string.  If a string pointed to by s is an empty
     string, a64l() returns 0.

     The l64a() function returns a pointer to the radix-64 representation.  If
     value is 0, l64a() returns a pointer to an empty string.

SEE ALSO
     strtoul(3)

HISTORY
     The a64l(), l64a(), and l64a_r() functions are derived from NetBSD with
     modifications.  They appeared in FreeBSD 6.1.

AUTHORS
     The a64l(), l64a(), and l64a_r() functions were added to FreeBSD by Tom
     Rhodes <trhodes@FreeBSD.org>.  Almost all of this manual page came from
     the POSIX standard.

FreeBSD 13.1-RELEASE-p6        November 20, 2005       FreeBSD 13.1-RELEASE-p6