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 <
[email protected]>. Almost all of this manual page came from
the POSIX standard.
FreeBSD 14.1-RELEASE-p8 November 20, 2005 FreeBSD 14.1-RELEASE-p8