xref: /freebsd/share/man/man3/pthread_create.3 (revision 5521ff5a4d1929056e7ffc982fac3341ca54df7c)
1.\" Copyright (c) 1996 John Birrell <jb@cimlogic.com.au>.
2.\" All rights reserved.
3.\"
4.\" Redistribution and use in source and binary forms, with or without
5.\" modification, are permitted provided that the following conditions
6.\" are met:
7.\" 1. Redistributions of source code must retain the above copyright
8.\"    notice, this list of conditions and the following disclaimer.
9.\" 2. Redistributions in binary form must reproduce the above copyright
10.\"    notice, this list of conditions and the following disclaimer in the
11.\"    documentation and/or other materials provided with the distribution.
12.\" 3. All advertising materials mentioning features or use of this software
13.\"    must display the following acknowledgement:
14.\"	This product includes software developed by John Birrell.
15.\" 4. Neither the name of the author nor the names of any co-contributors
16.\"    may be used to endorse or promote products derived from this software
17.\"    without specific prior written permission.
18.\"
19.\" THIS SOFTWARE IS PROVIDED BY JOHN BIRRELL AND CONTRIBUTORS ``AS IS'' AND
20.\" ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
21.\" IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
22.\" ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
23.\" FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
24.\" DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
25.\" OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
26.\" HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
27.\" LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
28.\" OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
29.\" SUCH DAMAGE.
30.\"
31.\" $FreeBSD$
32.\"
33.Dd April 4, 1996
34.Dt PTHREAD_CREATE 3
35.Os BSD 4
36.Sh NAME
37.Nm pthread_create
38.Nd create a new thread
39.Sh LIBRARY
40.Lb libc_r
41.Sh SYNOPSIS
42.Fd #include <pthread.h>
43.Ft int
44.Fn pthread_create "pthread_t *thread" "const pthread_attr_t *attr" "void *(*start_routine)(void *)" "void *arg"
45.Sh DESCRIPTION
46The
47.Fn pthread_create
48function is used to create a new thread, with attributes specified by
49.Fa attr ,
50within a process.
51If
52.Fa attr
53is NULL, the default attributes are used.
54If the attributes specified by
55.Fa attr
56are modified later, the thread's attributes are not affected.
57Upon
58successful completion
59.Fn pthread_create
60will store the ID of the created thread in the location specified by
61.Fa thread .
62.Pp
63The thread is created executing
64.Fa start_routine
65with
66.Fa arg
67as its sole argument.
68If the
69.Fa start_routine
70returns, the effect is as if there was an implicit call to
71.Fn pthread_exit
72using the return value of
73.Fa start_routine
74as the exit status.
75Note that the thread in which
76.Fn main
77was originally invoked differs from this.
78When it returns from
79.Fn main ,
80the effect is as if there was an implicit call to
81.Fn exit
82using the return value of
83.Fn main
84as the exit status.
85.Pp
86The signal state of the new thread is initialized as:
87.Bl -bullet -offset indent
88.It
89The signal mask is inherited from the creating thread.
90.It
91The set of signals pending for the new thread is empty.
92.El
93.Sh RETURN VALUES
94If successful,  the
95.Fn pthread_create
96function will return zero.
97Otherwise an error number will be returned to
98indicate the error.
99.Sh ERRORS
100.Fn pthread_create
101will fail if:
102.Bl -tag -width Er
103.It Bq Er EAGAIN
104The system lacked the necessary resources to create another thread, or
105the system-imposed limit on the total number of threads in a process
106[PTHREAD_THREADS_MAX] would be exceeded.
107.It Bq Er EINVAL
108The value specified by
109.Fa attr
110is invalid.
111.El
112.Pp
113.Sh SEE ALSO
114.Xr fork 2 ,
115.Xr pthread_cleanup_pop 3 ,
116.Xr pthread_cleanup_push 3 ,
117.Xr pthread_exit 3 ,
118.Xr pthread_join 3
119.Sh STANDARDS
120.Fn pthread_create
121conforms to
122.St -p1003.1-96 .
123