/* _Fork implementation. Linux version. Copyright (C) 2021-2022 Free Software Foundation, Inc. This file is part of the GNU C Library. The GNU C Library 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) any later version. The GNU C Library 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 the GNU C Library; if not, see . */ #include #include pid_t _Fork (void) { pid_t pid = arch_fork (&THREAD_SELF->tid); if (pid == 0) { struct pthread *self = THREAD_SELF; /* Initialize the robust mutex list setting in the kernel which has been reset during the fork. We do not check for errors because if it fails here, it must have failed at process startup as well and nobody could have used robust mutexes. Before we do that, we have to clear the list of robust mutexes because we do not inherit ownership of mutexes from the parent. We do not have to set self->robust_head.futex_offset since we do inherit the correct value from the parent. We do not need to clear the pending operation because it must have been zero when fork was called. */ #if __PTHREAD_MUTEX_HAVE_PREV self->robust_prev = &self->robust_head; #endif self->robust_head.list = &self->robust_head; INTERNAL_SYSCALL_CALL (set_robust_list, &self->robust_head, sizeof (struct robust_list_head)); } return pid; } libc_hidden_def (_Fork)