1<?xml version="1.0" standalone="yes"?>
2<programlisting>
3for (auto &amp; s : seq)
4    s.<methodname alt="boost::process::extend::handler::on_setup">on_setup</methodname>(*this);
5
6if (<methodname alt="boost::process::extend::posix_executor::error">error</methodname>())
7{
8    for (auto &amp; s : seq)
9       s.<methodname alt="boost::process::extend::handler::on_error">on_error</methodname>(*this, <methodname alt="boost::process::extend::posix_executor::error">error</methodname>());
10    return <classname alt="boost::process::child">child</classname>();
11}
12
13pid = <ulink url="http://pubs.opengroup.org/onlinepubs/009695399/functions/fork.html">fork()</ulink>
14<methodname alt="boost::process::extend::handler::on_setup">on_setup</methodname>(*this);
15
16if (pid == -1) //fork error
17{
18    <methodname alt="boost::process::extend::posix_executor::set_error">set_error</methodname>(<functionname alt="boost::process::extend::get_last_error">get_last_error</functionname>());
19    for (auto &amp; s : seq)
20        s.<methodname alt="boost::process::extend::handler::on_fork_error">on_fork_error</methodname>(*this, <methodname alt="boost::process::extend::posix_executor::error">error</methodname>());
21    for (auto &amp; s : seq)
22        s.<methodname alt="boost::process::extend::handler::on_error">on_error</methodname>(*this, <methodname alt="boost::process::extend::posix_executor::error">error</methodname>());
23    return <classname alt="boost::process::child">child</classname>()
24}
25else if (pid == 0) //child process
26{
27    for (auto &amp; s : seq)
28        s.<methodname alt="boost::process::extend::handler::on_exec_setup">on_exec_setup</methodname>(*this);
29    <ulink url="http://pubs.opengroup.org/onlinepubs/009695399/functions/exec.html">execve</ulink>(exe, cmd_line, env);
30    auto ec = <functionname alt="boost::process::extend::get_last_error">get_last_error</functionname>();
31    for (auto &amp; s : seq)
32        s.<methodname alt="boost::process::extend::handler::on_exec_error">on_exec_error</methodname>(*this);
33
34    <emphasis>unspecified();</emphasis>//here the error is send to the father process interally
35
36    <ulink url="http://en.cppreference.com/w/cpp/utility/program/exit">std::exit</ulink>(<ulink url="http://en.cppreference.com/w/c/program/EXIT_status">EXIT_FAILURE</ulink>);
37    return <classname alt="boost::process::child">child</classname>(); //for C++ compliance
38}
39
40<classname alt="boost::process::child">child</classname> c(pid, exit_code);
41
42<emphasis>unspecified();</emphasis>//here, we read the the error from the child process
43
44if (<methodname alt="boost::process::extend::posix_executor::error">error</methodname>())
45    for (auto &amp; s : seq)
46        s.<methodname alt="boost::process::extend::handler::on_error">on_error</methodname>(*this, <methodname alt="boost::process::extend::posix_executor::error">error</methodname>());
47else
48    for (auto &amp; s : seq)
49        s.<methodname alt="boost::process::extend::handler::on_error">on_success</methodname>(*this);
50
51//now we check again, because a on_success handler might've errored.
52if (<methodname alt="boost::process::extend::posix_executor::error">error</methodname>())
53{
54    for (auto &amp; s : seq)
55        s.<methodname alt="boost::process::extend::handler::on_error">on_error</methodname>(*this, <methodname alt="boost::process::extend::posix_executor::error">error</methodname>());
56    return <classname alt="boost::process::child">child</classname>();
57}
58else
59    return c;
60</programlisting>