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/*****************************************************************************
* Copyright 2014 - 2015 Yichao Yu <yyc1992@gmail.com> *
* *
* This program is free software; you can redistribute it and/or modify *
* it under the terms of the GNU Lesser General Public License as *
* published by the Free Software Foundation; either version 2.1 of the *
* License, or (at your option) version 3, or any later version accepted *
* by the membership of KDE e.V. (or its successor approved by the *
* membership of KDE e.V.), which shall act as a proxy defined in *
* Section 6 of version 3 of the license. *
* *
* This program is distributed in the hope that it will be useful, *
* but WITHOUT ANY WARRANTY; without even the implied warranty of *
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU *
* Lesser General Public License for more details. *
* *
* You should have received a copy of the GNU Lesser General Public *
* License along with this library. If not, *
* see <http://www.gnu.org/licenses/>. *
*****************************************************************************/
#include <qtcurve-utils/process.h>
#include <assert.h>
#include <unistd.h>
#include <time.h>
#include <signal.h>
#include <sys/wait.h>
int pipe_fds[2];
long num;
static void
forkCb(void*)
{
write(pipe_fds[1], &num, sizeof(num));
}
static void
sigchld_handler(int)
{
wait(nullptr);
}
int
main()
{
int res = pipe(pipe_fds);
assert(res == 0);
srandom(time(nullptr));
num = random();
struct sigaction sa;
memset(&sa, 0, sizeof(struct sigaction));
sa.sa_handler = sigchld_handler;
sigemptyset(&sa.sa_mask);
sa.sa_flags = SA_RESTART;
sigaction(SIGCHLD, &sa, nullptr);
if (fork() == 0) {
sleep(4);
return 0;
}
alarm(1);
bool fork_res = qtcForkBackground(forkCb, nullptr);
assert(fork_res);
long num_sent = 0;
ssize_t read_res = read(pipe_fds[0], &num_sent, sizeof(num_sent));
assert(read_res == sizeof(num_sent));
assert(num_sent = num);
return 0;
}
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