A64L(3C) Standard C Library Functions A64L(3C)


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


#include <stdlib.h>

long a64l(const char *s);

char *l64a(long l);


These functions maintain numbers stored in base-64 ASCII characters that
define a notation by which long integers can be represented by up to six
characters. Each character represents a "digit" in a radix-64 notation.

The characters used to represent "digits" are as follows:

|Character | Digit |
|. | 0 |
|/ | 1 |
|0-9 | 2-11 |
|A-Z | 12-37 |
|a-z | 38-63 |

The a64l() function takes a pointer to a null-terminated base-64
representation and returns a corresponding long value. If the string
pointed to by s contains more than six characters, a64l() uses the first

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.

The l64a() function takes a long argument and returns a pointer to the
corresponding base-64 representation. If the argument is 0, l64a()
returns a pointer to a null string.

The value returned by l64a() is a pointer into a static buffer, the
contents of which are overwritten by each call. In the case of
multithreaded applications, the return value is a pointer to thread
specific data.


See attributes(7) for descriptions of the following attributes:

|Interface Stability | Standard |
|MT-Level | MT-Safe |


attributes(7), standards(7)

July 24, 2002 A64L(3C)