BIO_s_null.3ossl 5.2 KB

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  135. .IX Title "BIO_S_NULL 3ossl"
  136. .TH BIO_S_NULL 3ossl "2024-09-03" "3.3.2" "OpenSSL"
  137. .\" For nroff, turn off justification. Always turn off hyphenation; it makes
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  140. .nh
  141. .SH "NAME"
  142. BIO_s_null \- null data sink
  143. .SH "SYNOPSIS"
  144. .IX Header "SYNOPSIS"
  145. .Vb 1
  146. \& #include <openssl/bio.h>
  147. \&
  148. \& const BIO_METHOD *BIO_s_null(void);
  149. .Ve
  150. .SH "DESCRIPTION"
  151. .IX Header "DESCRIPTION"
  152. \&\fBBIO_s_null()\fR returns the null sink \s-1BIO\s0 method. Data written to
  153. the null sink is discarded, reads return \s-1EOF.\s0
  154. .SH "NOTES"
  155. .IX Header "NOTES"
  156. A null sink \s-1BIO\s0 behaves in a similar manner to the Unix /dev/null
  157. device.
  158. .PP
  159. A null bio can be placed on the end of a chain to discard any data
  160. passed through it.
  161. .PP
  162. A null sink is useful if, for example, an application wishes to digest some
  163. data by writing through a digest bio but not send the digested data anywhere.
  164. Since a \s-1BIO\s0 chain must normally include a source/sink \s-1BIO\s0 this can be achieved
  165. by adding a null sink \s-1BIO\s0 to the end of the chain
  166. .SH "RETURN VALUES"
  167. .IX Header "RETURN VALUES"
  168. \&\fBBIO_s_null()\fR returns the null sink \s-1BIO\s0 method.
  169. .SH "COPYRIGHT"
  170. .IX Header "COPYRIGHT"
  171. Copyright 2000\-2016 The OpenSSL Project Authors. All Rights Reserved.
  172. .PP
  173. Licensed under the Apache License 2.0 (the \*(L"License\*(R"). You may not use
  174. this file except in compliance with the License. You can obtain a copy
  175. in the file \s-1LICENSE\s0 in the source distribution or at
  176. <https://www.openssl.org/source/license.html>.