xref: /freebsd/lib/libsys/aio_return.2 (revision 3fb8f1272b50cb87cb624b321f7b81e76627c437)
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25.Dd January 11, 2021
26.Dt AIO_RETURN 2
27.Os
28.Sh NAME
29.Nm aio_return
30.Nd retrieve return status of asynchronous I/O operation (REALTIME)
31.Sh LIBRARY
32.Lb libc
33.Sh SYNOPSIS
34.In aio.h
35.Ft ssize_t
36.Fn aio_return "struct aiocb *iocb"
37.Sh DESCRIPTION
38The
39.Fn aio_return
40system call returns the final status of the asynchronous I/O request
41associated with the structure pointed to by
42.Fa iocb .
43.Pp
44The
45.Fn aio_return
46system call
47should only be called once, to obtain the final status of an asynchronous
48I/O operation once it has completed
49.Xr ( aio_error 2
50returns something other than
51.Er EINPROGRESS ) .
52.Sh RETURN VALUES
53If the asynchronous I/O request has completed, the status is returned
54as described in
55.Xr read 2 ,
56.Xr readv 2 ,
57.Xr write 2 ,
58.Xr writev 2 ,
59or
60.Xr fsync 2 .
61Otherwise,
62.Fn aio_return
63returns \-1 and sets
64.Va errno
65to indicate the error condition.
66.Sh ERRORS
67The
68.Fn aio_return
69system call will fail if:
70.Bl -tag -width Er
71.It Bq Er EINVAL
72The
73.Fa iocb
74argument
75does not reference a completed asynchronous I/O request.
76.It Bq Er EINVAL
77The I/O operation was submitted with
78.Fn lio_listio ,
79and the value of the
80.Fa aio_lio_opcode
81is invalid.
82.El
83.Sh SEE ALSO
84.Xr aio_cancel 2 ,
85.Xr aio_error 2 ,
86.Xr aio_suspend 2 ,
87.Xr aio_waitcomplete 2 ,
88.Xr aio_write 2 ,
89.Xr fsync 2 ,
90.Xr read 2 ,
91.Xr write 2 ,
92.Xr aio 4
93.Sh STANDARDS
94The
95.Fn aio_return
96system call
97is expected to conform to the
98.St -p1003.1
99standard.
100.Sh HISTORY
101The
102.Fn aio_return
103system call first appeared in
104.Fx 3.0 .
105.Sh AUTHORS
106This
107manual page was written by
108.An Wes Peters Aq Mt wes@softweyr.com .
109