a64l(3p) — Linux manual page


A64L(3P)                POSIX Programmer's Manual               A64L(3P)

PROLOG         top

       This manual page is part of the POSIX Programmer's Manual.  The
       Linux implementation of this interface may differ (consult the
       corresponding Linux manual page for details of Linux behavior),
       or the interface may not be implemented on Linux.

NAME         top

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

SYNOPSIS         top

       #include <stdlib.h>

       long a64l(const char *s);
       char *l64a(long value);

DESCRIPTION         top

       These functions 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 shall be used for these

       The characters used to represent digits are '.'  (dot) 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 shall take a pointer to a radix-64
       representation, in which the first digit is the least
       significant, and return the corresponding long value. If the
       string pointed to by s contains more than six characters, a64l()
       shall use the first six. If the first six characters of the
       string contain a null terminator, a64l() shall use only
       characters preceding the null terminator. The a64l() function
       shall scan 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 shall take a long argument and return a
       pointer to the corresponding radix-64 representation. The
       behavior of l64a() is unspecified if value is negative.

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

       The l64a() function need not be thread-safe.

RETURN VALUE         top

       Upon successful completion, a64l() shall return the long value
       resulting from conversion of the input string. If a string
       pointed to by s is an empty string, a64l() shall return 0L.

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

ERRORS         top

       No errors are defined.

       The following sections are informative.

EXAMPLES         top



       If the type long contains more than 32 bits, the result of
       a64l(l64a(x)) is x in the low-order 32 bits.

RATIONALE         top

       This is not the same encoding as used by either encoding variant
       of the uuencode utility.



SEE ALSO         top


       The Base Definitions volume of POSIX.1‐2017, stdlib.h(0p)

       The Shell and Utilities volume of POSIX.1‐2017, uuencode(1p)

COPYRIGHT         top

       Portions of this text are reprinted and reproduced in electronic
       form from IEEE Std 1003.1-2017, Standard for Information
       Technology -- Portable Operating System Interface (POSIX), The
       Open Group Base Specifications Issue 7, 2018 Edition, Copyright
       (C) 2018 by the Institute of Electrical and Electronics
       Engineers, Inc and The Open Group.  In the event of any
       discrepancy between this version and the original IEEE and The
       Open Group Standard, the original IEEE and The Open Group
       Standard is the referee document. The original Standard can be
       obtained online at http://www.opengroup.org/unix/online.html .

       Any typographical or formatting errors that appear in this page
       are most likely to have been introduced during the conversion of
       the source files to man page format. To report such errors, see
       https://www.kernel.org/doc/man-pages/reporting_bugs.html .

IEEE/The Open Group               2017                          A64L(3P)

Pages that refer to this page: stdlib.h(0p)l64a(3p)