xref: /netbsd-src/lib/libc/sys/_lwp_create.2 (revision aaf4ece63a859a04e37cf3a7229b5fab0157cc06)
1.\"	$NetBSD: _lwp_create.2,v 1.3 2003/04/16 13:34:50 wiz Exp $
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3.\" Copyright (c) 2003 The NetBSD Foundation, Inc.
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6.\" This code is derived from software contributed to The NetBSD Foundation
7.\" by Jason R. Thorpe of Wasabi Systems, Inc.
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37.Dd January 13, 2003
38.Dt _LWP_CREATE 2
39.Os
40.Sh NAME
41.Nm _lwp_create
42.Nd create a new light-weight process
43.Sh LIBRARY
44.Lb libc
45.Sh SYNOPSIS
46.In lwp.h
47.Ft int
48.Fn _lwp_create "ucontext_t *context" "unsigned long flags" "lwpid_t *new_lwp"
49.Sh DESCRIPTION
50.Fn _lwp_create
51causes creation of a new light-weight process, or LWP, and adds it to the
52current process.
53The
54.Fa context
55argument specifies the initial execution context for the new LWP including
56signal mask, stack, and machine registers.
57.Pp
58The following flags affect the creation of the new LWP:
59.Bl -tag -width LWP_SUSPENDED
60.It LWP_DETACHED
61The LWP is created detached.
62The resources associated with a detached LWP will be automatically
63reclaimed by the system when the LWP exits.
64Otherwise, a terminated LWP's resources will not be reclaimed until
65its status is reported to another LWP via
66.Xr _lwp_wait 2 .
67.It LWP_SUSPENDED
68The LWP is created suspended, and will not begin execution until
69it is resumed by another LWP via
70.Xr _lwp_continue 2 .
71.\" __LWP_ASLWP is not yet implemented by the NetBSD kernel.
72.El
73.Pp
74The LWP ID of the new LWP is stored in the location pointed to by
75.Fa new_lwp .
76.Sh RETURN VALUES
77Upon successful completion,
78.Fn _lwp_create
79returns a value of 0.
80Otherwise, an error code is returned to indicate the error.
81.Sh ERRORS
82.Fn _lwp_create
83will fail and no LWP will be created if:
84.Bl -tag -width [EAGAIN]
85.It Bq Er EAGAIN
86The system-imposed limit on the total
87number of LWPs under execution would be exceeded.
88This limit is configuration-dependent.
89.It Bq Er ENOMEM
90There is insufficient swap space for the new LWP.
91.It Bq Er EFAULT
92The address pointed to by
93.Fa context
94or
95.Fa new_lwp
96is outside the process's allocated address space.
97.El
98.Sh SEE ALSO
99.Xr _lwp_continue 2 ,
100.Xr _lwp_exit 2 ,
101.Xr _lwp_wait 2 ,
102.Xr _lwp_makecontext 3
103.Sh HISTORY
104The
105.Fn _lwp_create
106system call first appeared in
107.Nx 2.0 .
108