| Server IP : 85.214.239.14 / Your IP : 18.119.118.237 Web Server : Apache/2.4.62 (Debian) System : Linux h2886529.stratoserver.net 4.9.0 #1 SMP Tue Jan 9 19:45:01 MSK 2024 x86_64 User : www-data ( 33) PHP Version : 7.4.18 Disable Function : pcntl_alarm,pcntl_fork,pcntl_waitpid,pcntl_wait,pcntl_wifexited,pcntl_wifstopped,pcntl_wifsignaled,pcntl_wifcontinued,pcntl_wexitstatus,pcntl_wtermsig,pcntl_wstopsig,pcntl_signal,pcntl_signal_get_handler,pcntl_signal_dispatch,pcntl_get_last_error,pcntl_strerror,pcntl_sigprocmask,pcntl_sigwaitinfo,pcntl_sigtimedwait,pcntl_exec,pcntl_getpriority,pcntl_setpriority,pcntl_async_signals,pcntl_unshare, MySQL : OFF | cURL : OFF | WGET : ON | Perl : ON | Python : ON | Sudo : ON | Pkexec : OFF Directory : /proc/3/cwd/proc/3/root/usr/share/doc/libffi-dev/html/ |
Upload File : |
<!DOCTYPE html PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN" "http://www.w3.org/TR/html4/loose.dtd">
<html>
<!-- Created by GNU Texinfo 6.8, https://www.gnu.org/software/texinfo/ -->
<head>
<meta http-equiv="Content-Type" content="text/html; charset=utf-8">
<!--
This manual is for libffi, a portable foreign function interface
library.
Copyright (C) 2008-2019, 2021, 2022 Anthony Green and Red Hat, Inc.
Permission is hereby granted, free of charge, to any person obtaining
a copy of this software and associated documentation files (the
"Software"), to deal in the Software without restriction, including
without limitation the rights to use, copy, modify, merge, publish,
distribute, sublicense, and/or sell copies of the Software, and to
permit persons to whom the Software is furnished to do so, subject to
the following conditions:
The above copyright notice and this permission notice shall be
included in all copies or substantial portions of the Software.
THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.
IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY
CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT,
TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE
SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
-->
<title>Closure Example (libffi: the portable foreign function interface library)</title>
<meta name="description" content="Closure Example (libffi: the portable foreign function interface library)">
<meta name="keywords" content="Closure Example (libffi: the portable foreign function interface library)">
<meta name="resource-type" content="document">
<meta name="distribution" content="global">
<meta name="Generator" content="makeinfo">
<meta name="viewport" content="width=device-width,initial-scale=1">
<link href="index.html" rel="start" title="Top">
<link href="Index.html" rel="index" title="Index">
<link href="Using-libffi.html" rel="up" title="Using libffi">
<link href="Thread-Safety.html" rel="next" title="Thread Safety">
<link href="The-Closure-API.html" rel="prev" title="The Closure API">
<style type="text/css">
<!--
a.copiable-anchor {visibility: hidden; text-decoration: none; line-height: 0em}
a.summary-letter {text-decoration: none}
blockquote.indentedblock {margin-right: 0em}
div.display {margin-left: 3.2em}
div.example {margin-left: 3.2em}
kbd {font-style: oblique}
pre.display {font-family: inherit}
pre.format {font-family: inherit}
pre.menu-comment {font-family: serif}
pre.menu-preformatted {font-family: serif}
span.nolinebreak {white-space: nowrap}
span.roman {font-family: initial; font-weight: normal}
span.sansserif {font-family: sans-serif; font-weight: normal}
span:hover a.copiable-anchor {visibility: visible}
ul.no-bullet {list-style: none}
-->
</style>
</head>
<body lang="en">
<div class="section" id="Closure-Example">
<div class="header">
<p>
Next: <a href="Thread-Safety.html" accesskey="n" rel="next">Thread Safety</a>, Previous: <a href="The-Closure-API.html" accesskey="p" rel="prev">The Closure API</a>, Up: <a href="Using-libffi.html" accesskey="u" rel="up">Using libffi</a> [<a href="Index.html" title="Index" rel="index">Index</a>]</p>
</div>
<hr>
<span id="Closure-Example-1"></span><h3 class="section">2.6 Closure Example</h3>
<p>A trivial example that creates a new <code>puts</code> by binding
<code>fputs</code> with <code>stdout</code>.
</p>
<div class="example">
<pre class="example">#include <stdio.h>
#include <ffi.h>
/* Acts like puts with the file given at time of enclosure. */
void puts_binding(ffi_cif *cif, void *ret, void* args[],
void *stream)
{
*(ffi_arg *)ret = fputs(*(char **)args[0], (FILE *)stream);
}
typedef int (*puts_t)(char *);
int main()
{
ffi_cif cif;
ffi_type *args[1];
ffi_closure *closure;
void *bound_puts;
int rc;
/* Allocate closure and bound_puts */
closure = ffi_closure_alloc(sizeof(ffi_closure), &bound_puts);
if (closure)
{
/* Initialize the argument info vectors */
args[0] = &ffi_type_pointer;
/* Initialize the cif */
if (ffi_prep_cif(&cif, FFI_DEFAULT_ABI, 1,
&ffi_type_sint, args) == FFI_OK)
{
/* Initialize the closure, setting stream to stdout */
if (ffi_prep_closure_loc(closure, &cif, puts_binding,
stdout, bound_puts) == FFI_OK)
{
rc = ((puts_t)bound_puts)("Hello World!");
/* rc now holds the result of the call to fputs */
}
}
}
/* Deallocate both closure, and bound_puts */
ffi_closure_free(closure);
return 0;
}
</pre></div>
</div>
</body>
</html>