xref: /freebsd/lib/libsys/rfork_thread.3 (revision 5ca8e32633c4ffbbcd6762e5888b6a4ba0708c6c)
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26.Dd February 6, 2011
27.Dt RFORK_THREAD 3
28.Os
29.Sh NAME
30.Nm rfork_thread
31.Nd create a rfork-based process thread
32.Sh LIBRARY
33.Lb libc
34.Sh SYNOPSIS
35.In unistd.h
36.Ft pid_t
37.Fn rfork_thread "int flags" "void *stack" "int (*func)(void *arg)" "void *arg"
38.Sh DESCRIPTION
39.Bf -symbolic
40The
41.Fn rfork_thread
42function has been deprecated in favor of
43.Xr pthread_create 3 .
44.Ef
45.Pp
46The
47.Fn rfork_thread
48function
49is a helper function for
50.Xr rfork 2 .
51It arranges for a new process to be created and the child process will
52call the specified function with the specified argument, while running on
53the supplied stack.
54.Pp
55Using this function should avoid the need to implement complex stack
56swap code.
57.Sh RETURN VALUES
58Upon successful completion,
59.Fn rfork_thread
60returns the process ID of the child process to the parent process.
61Otherwise, a value of -1 is returned
62to the parent process, no child process is created, and the global
63variable
64.Va errno
65is set to indicate the error.
66.Pp
67The child process context is not aware of a return from the
68.Fn rfork_thread
69function as it begins executing directly with the supplied function.
70.Sh ERRORS
71See
72.Xr rfork 2
73for error return codes.
74.Sh SEE ALSO
75.Xr fork 2 ,
76.Xr intro 2 ,
77.Xr minherit 2 ,
78.Xr rfork 2 ,
79.Xr vfork 2 ,
80.Xr pthread_create 3
81.Sh HISTORY
82The
83.Fn rfork_thread
84function first appeared in
85.Fx 4.3 .
86