Android_verify/third_party/android-libs/share/man/man3/BIO_f_readbuffer.3ossl

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.\" ========================================================================
.\"
.IX Title "BIO_F_READBUFFER 3ossl"
.TH BIO_F_READBUFFER 3ossl "2024-09-03" "3.3.2" "OpenSSL"
.\" For nroff, turn off justification.  Always turn off hyphenation; it makes
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.nh
.SH "NAME"
BIO_f_readbuffer
\&\- read only buffering BIO that supports BIO_tell() and BIO_seek()
.SH "SYNOPSIS"
.IX Header "SYNOPSIS"
.Vb 1
\& #include <openssl/bio.h>
\&
\& const BIO_METHOD *BIO_f_readbuffer(void);
.Ve
.SH "DESCRIPTION"
.IX Header "DESCRIPTION"
\&\fBBIO_f_readbuffer()\fR returns the read buffering \s-1BIO\s0 method.
.PP
This \s-1BIO\s0 filter can be inserted on top of \s-1BIO\s0's that do not support \fBBIO_tell()\fR
or \fBBIO_seek()\fR (e.g. A file \s-1BIO\s0 that uses stdin).
.PP
Data read from a read buffering \s-1BIO\s0 comes from an internal buffer which is
filled from the next \s-1BIO\s0 in the chain.
.PP
\&\fBBIO_gets()\fR is supported for read buffering BIOs.
Writing data to a read buffering \s-1BIO\s0 is not supported.
.PP
Calling \fBBIO_reset()\fR on a read buffering \s-1BIO\s0 does not clear any buffered data.
.SH "NOTES"
.IX Header "NOTES"
Read buffering BIOs implement \fBBIO_read_ex()\fR by using \fBBIO_read_ex()\fR operations
on the next \s-1BIO\s0 (e.g. a file \s-1BIO\s0) in the chain and storing the result in an
internal buffer, from which bytes are given back to the caller as appropriate
for the call. \fBBIO_read_ex()\fR is guaranteed to give the caller the number of bytes
it asks for, unless there's an error or end of communication is reached in the
next \s-1BIO.\s0 The internal buffer can grow to cache the entire contents of the next
\&\s-1BIO\s0 in the chain. \fBBIO_seek()\fR uses the internal buffer, so that it can only seek
into data that is already read.
.SH "RETURN VALUES"
.IX Header "RETURN VALUES"
\&\fBBIO_f_readbuffer()\fR returns the read buffering \s-1BIO\s0 method.
.SH "SEE ALSO"
.IX Header "SEE ALSO"
\&\fBbio\fR\|(7),
\&\fBBIO_read\fR\|(3),
\&\fBBIO_gets\fR\|(3),
\&\fBBIO_reset\fR\|(3),
\&\fBBIO_ctrl\fR\|(3).
.SH "COPYRIGHT"
.IX Header "COPYRIGHT"
Copyright 2021 The OpenSSL Project Authors. All Rights Reserved.
.PP
Licensed under the Apache License 2.0 (the \*(L"License\*(R").  You may not use
this file except in compliance with the License.  You can obtain a copy
in the file \s-1LICENSE\s0 in the source distribution or at
<https://www.openssl.org/source/license.html>.