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BASE64(3)		    Library Functions Manual		     BASE64(3)

NAME
       b64_encoder_create, b64_decoder_create -- base-64 encoder and decoder

LIBRARY
       PDEL Library (libpdel, -lpdel)

SYNOPSIS
       #include	<pdel/io/filter.h>
       #include	<pdel/io/base64.h>

       struct filter *
       b64_encoder_create(const	char *charset);

       struct filter *
       b64_decoder_create(const	char *charset, int strict);

       extern const char b64_rfc2045_charset[];

DESCRIPTION
       These  routines	create	filter objects (see filter(3)) that encode and
       decode binary data using	base-64	encoding.

       Both functions take a charset argument.	If equal to NULL, then the de-
       fault (RFC 2045)	character set is used.	Otherwise, charset must	 point
       to a string with	65 unique characters.  The first 64 are	used to	encode
       the  data, while	the last character is used as a	pad character when the
       data length is not a multiple of	three.

       b64_encoder_create() returns a new encoding filter.   For  every	 three
       bytes  input  to	 the  filter, four bytes from the chosen character set
       will be output.	If the input length is not a multiple of  three,  then
       one  or	two  pad characters will be added at the end of	the output, so
       that the	output length of the filter is always a	multiple of four.

       b64_decoder_create() returns a new decoding filter.  Every  four	 bytes
       input  to  the filter are decoded into up to three bytes	of output.  If
       strict is non-zero, then	any malformed input causes an  internal	 error
       to  be generated	in the filter, with errno set to EINVAL. Malformed in-
       put is any input	character not from the chosen character	set.   In  any
       case, the pad character is always ignored.  If strict is	zero, then any
       unrecognized  characters	are simply ignored, rather than	causing	an er-
       ror.

       b64_encoder_create() always generates  strings  that  are  accepted  by
       b64_decoder_create() in strict mode, when created with the same charac-
       ter set.

       The RFC 2045 character set is avilable in b64_rfc2045_charset.

RETURN VALUES
       If    there    was    a	  system   error,   b64_encoder_create()   and
       b64_encoder_create() return NULL	with  errno  set  to  the  appropriate
       value.  If an invalid charset is	passed,	errno will be set to EINVAL.

SEE ALSO
       filter(3), libpdel(3)

       N.  Freed  and  N.  Borenstein,	Multipurpose  Internet Mail Extensions
       (MIME) Part One:	Format of Internet Message Bodies, RFC 2045.

HISTORY
       The   PDEL   library   was   developed	at   Packet    Design,	  LLC.
       http://www.packetdesign.com/

AUTHORS
       Archie Cobbs <archie@freebsd.org>

FreeBSD	ports 15.0		April 22, 2002			     BASE64(3)

Want to link to this manual page? Use this URL:
<https://man.freebsd.org/cgi/man.cgi?query=b64_decoder_create&sektion=3&manpath=FreeBSD+Ports+15.0>

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