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 represents 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 repre-
sentation and returns a corresponding 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, decod-
ing 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.
l64a() takes a long integer argument value and returns a pointer to the
corresponding radix-64 representation.
RETURN VALUES
On success, a64l() returns a 32-bit representation of s. If s is a null
pointer or if it contains digits 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 con-
tents of which will be overwritten 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
Mac OS X 10.8 - Generated Sun Aug 26 09:02:06 CDT 2012