mirror of https://github.com/mkerrisk/man-pages
109 lines
2.1 KiB
Groff
109 lines
2.1 KiB
Groff
\t
|
|
.\" Copyright 2002 walter harms (walter.harms@informatik.uni-oldenburg.de)
|
|
.\"
|
|
.\" %%%LICENSE_START(GPL_NOVERSION_ONELINE)
|
|
.\" Distributed under GPL
|
|
.\" %%%LICENSE_END
|
|
.\"
|
|
.\" Corrected, aeb, 2002-05-30
|
|
.\"
|
|
.TH A64L 3 2021-03-22 "" "Linux Programmer's Manual"
|
|
.SH NAME
|
|
a64l, l64a \- convert between long and base-64
|
|
.SH SYNOPSIS
|
|
.nf
|
|
.B #include <stdlib.h>
|
|
.PP
|
|
.BI "long a64l(const char *" str64 );
|
|
.BI "char *l64a(long " value );
|
|
.fi
|
|
.PP
|
|
.RS -4
|
|
Feature Test Macro Requirements for glibc (see
|
|
.BR feature_test_macros (7)):
|
|
.RE
|
|
.PP
|
|
.BR a64l (),
|
|
.BR l64a ():
|
|
.nf
|
|
_XOPEN_SOURCE >= 500
|
|
.\" || _XOPEN_SOURCE && _XOPEN_SOURCE_EXTENDED
|
|
|| /* Glibc since 2.19: */ _DEFAULT_SOURCE
|
|
|| /* Glibc <= 2.19: */ _SVID_SOURCE
|
|
.fi
|
|
.SH DESCRIPTION
|
|
These functions provide a conversion between 32-bit long integers
|
|
and little-endian base-64 ASCII strings (of length zero to six).
|
|
If the string used as argument for
|
|
.BR a64l ()
|
|
has length greater than six, only the first six bytes are used.
|
|
If the type
|
|
.I long
|
|
has more than 32 bits, then
|
|
.BR l64a ()
|
|
uses only the low order 32 bits of
|
|
.IR value ,
|
|
and
|
|
.BR a64l ()
|
|
sign-extends its 32-bit result.
|
|
.PP
|
|
The 64 digits in the base-64 system are:
|
|
.PP
|
|
.RS
|
|
.nf
|
|
\&\(aq.\(aq represents a 0
|
|
\&\(aq/\(aq represents a 1
|
|
0-9 represent 2-11
|
|
A-Z represent 12-37
|
|
a-z represent 38-63
|
|
.fi
|
|
.RE
|
|
.PP
|
|
So 123 = 59*64\(ha0 + 1*64\(ha1 = "v/".
|
|
.SH ATTRIBUTES
|
|
For an explanation of the terms used in this section, see
|
|
.BR attributes (7).
|
|
.ad l
|
|
.nh
|
|
.TS
|
|
allbox;
|
|
lbx lb lb
|
|
l l l.
|
|
Interface Attribute Value
|
|
T{
|
|
.BR l64a ()
|
|
T} Thread safety MT-Unsafe race:l64a
|
|
T{
|
|
.BR a64l ()
|
|
T} Thread safety MT-Safe
|
|
.TE
|
|
.hy
|
|
.ad
|
|
.sp 1
|
|
.SH CONFORMING TO
|
|
POSIX.1-2001, POSIX.1-2008.
|
|
.SH NOTES
|
|
The value returned by
|
|
.BR l64a ()
|
|
may be a pointer to a static buffer, possibly overwritten
|
|
by later calls.
|
|
.PP
|
|
The behavior of
|
|
.BR l64a ()
|
|
is undefined when
|
|
.I value
|
|
is negative.
|
|
If
|
|
.I value
|
|
is zero, it returns an empty string.
|
|
.PP
|
|
These functions are broken in glibc before 2.2.5
|
|
(puts most significant digit first).
|
|
.PP
|
|
This is not the encoding used by
|
|
.BR uuencode (1).
|
|
.SH SEE ALSO
|
|
.BR uuencode (1),
|
|
.\" .BR itoa (3),
|
|
.BR strtoul (3)
|