xref: /freebsd/lib/libsys/aio_suspend.2 (revision 59c8e88e72633afbc47a4ace0d2170d00d51f7dc)
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25.Dd October 23, 2017
26.Dt AIO_SUSPEND 2
27.Os
28.Sh NAME
29.Nm aio_suspend
30.Nd suspend until asynchronous I/O operations or timeout complete (REALTIME)
31.Sh LIBRARY
32.Lb libc
33.Sh SYNOPSIS
34.In aio.h
35.Ft int
36.Fn aio_suspend "const struct aiocb *const iocbs[]" "int niocb" "const struct timespec *timeout"
37.Sh DESCRIPTION
38The
39.Fn aio_suspend
40system call suspends the calling process until at least one of the
41specified asynchronous I/O requests have completed, a signal is
42delivered, or the
43.Fa timeout
44has passed.
45.Pp
46The
47.Fa iocbs
48argument
49is an array of
50.Fa niocb
51pointers to asynchronous I/O requests.
52Array members containing
53null pointers will be silently ignored.
54.Pp
55If
56.Fa timeout
57is not a null pointer, it specifies a maximum interval to suspend.
58If
59.Fa timeout
60is a null pointer, the suspend blocks indefinitely.
61To effect a
62poll, the
63.Fa timeout
64should point to a zero-value timespec structure.
65.Sh RETURN VALUES
66If one or more of the specified asynchronous I/O requests have
67completed,
68.Fn aio_suspend
69returns 0.
70Otherwise it returns -1 and sets
71.Va errno
72to indicate the error, as enumerated below.
73.Sh ERRORS
74The
75.Fn aio_suspend
76system call will fail if:
77.Bl -tag -width Er
78.It Bq Er EAGAIN
79the
80.Fa timeout
81expired before any I/O requests completed.
82.It Bq Er EINVAL
83The
84.Fa iocbs
85argument
86contains more asynchronous I/O requests than the
87.Va vfs.aio.max_aio_queue_per_proc
88.Xr sysctl 8
89variable, or at least one of the requests is not valid.
90.It Bq Er EINTR
91the suspend was interrupted by a signal.
92.El
93.Sh SEE ALSO
94.Xr aio_cancel 2 ,
95.Xr aio_error 2 ,
96.Xr aio_return 2 ,
97.Xr aio_waitcomplete 2 ,
98.Xr aio_write 2 ,
99.Xr aio 4
100.Sh STANDARDS
101The
102.Fn aio_suspend
103system call
104is expected to conform to the
105.St -p1003.1
106standard.
107.Sh HISTORY
108The
109.Fn aio_suspend
110system call first appeared in
111.Fx 3.0 .
112.Sh AUTHORS
113This
114manual page was written by
115.An Wes Peters Aq Mt wes@softweyr.com .
116