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Diffstat (limited to 'static/openbsd/man9/fork1.9')
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diff --git a/static/openbsd/man9/fork1.9 b/static/openbsd/man9/fork1.9 new file mode 100644 index 00000000..e592b902 --- /dev/null +++ b/static/openbsd/man9/fork1.9 @@ -0,0 +1,167 @@ +.\" $OpenBSD: fork1.9,v 1.32 2022/12/29 06:49:34 jmc Exp $ +.\" $NetBSD: fork1.9,v 1.3 1999/03/16 00:40:47 garbled Exp $ +.\" +.\" Copyright (c) 1998 The NetBSD Foundation, Inc. +.\" All rights reserved. +.\" +.\" This code is derived from software contributed to The NetBSD Foundation +.\" by Jason R. Thorpe of the Numerical Aerospace Simulation Facility, +.\" NASA Ames Research Center. +.\" +.\" Redistribution and use in source and binary forms, with or without +.\" modification, are permitted provided that the following conditions +.\" are met: +.\" 1. Redistributions of source code must retain the above copyright +.\" notice, this list of conditions and the following disclaimer. +.\" 2. Redistributions in binary form must reproduce the above copyright +.\" notice, this list of conditions and the following disclaimer in the +.\" documentation and/or other materials provided with the distribution. +.\" +.\" THIS SOFTWARE IS PROVIDED BY THE NETBSD FOUNDATION, INC. AND CONTRIBUTORS +.\" ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED +.\" TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR +.\" PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE FOUNDATION OR CONTRIBUTORS +.\" BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR +.\" CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF +.\" SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS +.\" INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN +.\" CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) +.\" ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE +.\" POSSIBILITY OF SUCH DAMAGE. +.\" +.Dd $Mdocdate: December 29 2022 $ +.Dt FORK1 9 +.Os +.Sh NAME +.Nm fork1 +.Nd create a new process +.Sh SYNOPSIS +.In sys/types.h +.In sys/proc.h +.Ft int +.Fo fork1 +.Fa "struct proc *p1" +.Fa "int flags" +.Fa "void (*func)(void *)" +.Fa "void *arg" +.Fa "register_t *retval" +.Fa "struct proc **rnewprocp" +.Fc +.Sh DESCRIPTION +.Fn fork1 +creates a new process out of +.Ar p1 , +which should be the current thread. +This function is used primarily to implement the +.Xr fork 2 +and +.Xr vfork 2 +system calls, as well as the +.Xr kthread_create 9 +function. +.Pp +The +.Ar flags +argument is used to control the behavior of the fork and is created by +a bitwise-OR of the following values: +.Bl -tag -width FORK_SHAREFILES +.It Dv FORK_FORK +The call is done by the +.Xr fork 2 +system call. +Used only for statistics. +.It Dv FORK_VFORK +The call is done by the +.Xr vfork 2 +system call. +Used only for statistics. +.It Dv FORK_PPWAIT +Suspend the parent process until the child is terminated (by calling +.Xr _exit 2 +or abnormally), or makes a call to +.Xr execve 2 . +.It Dv FORK_SHAREFILES +Let the child share the file descriptor table with the parent through +.Fn fdshare . +The default behavior is to copy the table through +.Fn fdcopy . +.It Dv FORK_IDLE +The new thread will be left in the +.Dv SIDL +state. +The default behavior is to make it runnable and add it to the run queue. +.It Dv FORK_NOZOMBIE +The child will be dissociated from the parent and will not leave a status +for the parent to collect. +See +.Xr wait 2 . +.It Dv FORK_SHAREVM +The child will share the parent's address space. +The default behavior is +that the child gets a copy-on-write copy of the address space. +.It Dv FORK_SYSTEM +The child will be marked as a system process. +.It Dv FORK_PTRACE +The child will start with tracing enabled, as if +ptrace(PT_TRACE_ME, 0, 0, 0) had been invoked in the child. +.El +.Pp +The new thread will begin execution by calling +.Fa func , +which must not be +.Dv NULL . +If +.Fa arg +is not +.Dv NULL , +it is passed as the argument to +.Fa func . +Otherwise, a pointer to the new process's only thread is passed. +.Pp +If +.Fa retval +is not +.Dv NULL , +the PID of the child process will be stored in +.Fa *retval +on successful completion. +.Pp +If +.Fa rnewprocp +is not +.Dv NULL , +the newly created thread is stored in +.Fa *rnewprocp +on successful completion. +.Sh RETURN VALUES +Upon successful completion of the fork operation, +.Fn fork1 +returns 0. +Otherwise, the following error values are returned: +.Bl -tag -width [EAGAIN] +.It Bq Er EAGAIN +The system limits on the total number of threads or processes would +be exceeded. +.It Bq Er EAGAIN +The limit +.Dv RLIMIT_NPROC +on the total number of processes under execution by this +user id would be exceeded. +.It Bq Er ENOMEM +There is insufficient swap space for the new thread. +.El +.Sh SEE ALSO +.Xr execve 2 , +.Xr fork 2 , +.Xr vfork 2 , +.Xr kthread_create 9 , +.Xr psignal 9 , +.Xr tfind 9 +.Sh CAVEATS +The +.Nm +function semantics are specific to +.Ox . +Other +.Bx +systems have different semantics. |