man2/io_setup.2

   1 .\" Copyright (C) 2003 Free Software Foundation, Inc.
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  23 .TH "IO_SETUP" 2 "2003-02-21" "Linux 2.4" "Linux Programmer's Manual"
  24 .SH NAME
  25 io_setup \- create an asynchronous I/O context
  26 .SH "SYNOPSIS"
  27 .nf
  28 .\" .ad l
  29 .\" .hy 0
  30 .B #include <libaio.h>
  31 .\" #include <linux/aio.h>
  32 .sp
  33 .\" .HP 15
  34 .BI "int io_setup(unsigned " nr_events ", aio_context_t *" ctxp );
  35 .\" .ad
  36 .\" .hy
  37 .fi
  38 .SH "DESCRIPTION"
  39 .PP
  40 \fBio_setup\fR() creates an asynchronous I/O context capable of receiving
  41 at least \fInr_events\fR.
  42 \fIctxp\fR must not point to an AIO context that already exists, and must
  43 be initialized to 0 prior to the call.
  44 On successful creation of the AIO context, \fI*ctxp\fR is filled in
  45 with the resulting handle.
  46 .SH "RETURN VALUE"
  47 .PP
  48 \fBio_setup\fR() returns 0 on success;
  49 on failure, it returns one of the errors listed under ERRORS.
  50 .SH "ERRORS"
  51 .TP
  52 .B EINVAL
  53 \fIctxp\fR is not initialized, or the specified \fInr_events\fR
  54 exceeds internal limits. \fInr_events\fR should be greater than 0.
  55 .TP
  56 .B EFAULT
  57 An invalid pointer is passed for \fIctxp\fR.
  58 .TP
  59 .B ENOMEM
  60 Insufficient kernel resources are available.
  61 .TP
  62 .B EAGAIN
  63 The specified \fInr_events\fR exceeds the user's limit of available events.
  64 .TP
  65 .B ENOSYS
  66 \fBio_setup\fR() is not implemented on this architecture.
  67 .SH "CONFORMING TO"
  68 .PP
  69 \fBio_setup\fR() is Linux specific and should not be used in programs
  70 that are intended to be portable.
  71 .SH "VERSIONS"
  72 .PP
  73 The asynchronous I/O system calls first appeared in Linux 2.5, August 2002.
  74 .SH "SEE ALSO"
  75 .PP
  76 \fBio_destroy\fR(2), \fBio_getevents\fR(2), \fBio_submit\fR(2),
  77 \fBio_cancel\fR(2).
  78 .\" .SH "NOTES"
  79 .\" .PP
  80 .\" The asynchronous I/O system calls were written by Benjamin LaHaise.
  81 .\" .SH AUTHOR
  82 .\" Kent Yoder.