io_queue_init(2) [debian man page]

io_queue_init(2)						     Linux AIO							  io_queue_init(2)

NAME

       io_queue_init - Initialize asynchronous io state machine

SYNOPSIS

       #include <errno.h>

       #include <libaio.h>

       int io_queue_init(int maxevents, io_context_t *ctx);

DESCRIPTION

       io_queue_init  Attempts	to  create  an	aio context capable of receiving at least maxevents events.  ctx must point to an aio context that
       already exists and must be initialized to 0 before the call.  If the operation is successful, *cxtp is filled with the resulting handle.

RETURN VALUES

       On success, io_queue_init returns 0.  Otherwise, -error is return, where error is one of the Exxx values defined in the Errors section.

ERRORS

       EFAULT iocbs referenced data outside of the program's accessible address space.

       EINVAL maxevents is <= 0 or ctx is an invalid memory location.

       ENOSYS Not implemented.

       EAGAIN maxevents > max_aio_reqs where max_aio_reqs is a tunable value.

SEE ALSO

       io(3),  io_cancel(3),   io_fsync(3),   io_getevents(3),	 io_prep_fsync(3),   io_prep_pread(3),	 io_prep_pwrite(3),   io_queue_release(3),
       io_queue_run(3), io_queue_wait(3), io_set_callback(3), io_submit(3), errno(3).

Linux 2.4							    2009-06-10							  io_queue_init(2)

IO_SUBMIT(2)						     Linux Programmer's Manual						      IO_SUBMIT(2)

NAME

       io_submit - submit asynchronous I/O blocks for processing

SYNOPSIS

       #include <linux/aio_abi.h>	   /* Defines needed types */

       int io_submit(aio_context_t ctx_id, long nr, struct iocb **iocbpp);

       Note: There is no glibc wrapper for this system call; see NOTES.

DESCRIPTION

       The  io_submit() system call queues nr I/O request blocks for processing in the AIO context ctx_id.  The iocbpp argument should be an array
       of nr AIO control blocks, which will be submitted to context ctx_id.

RETURN VALUE

       On success, io_submit() returns the number of iocbs submitted (which may be 0 if nr is zero).  For the failure return, see NOTES.

ERRORS

       EAGAIN Insufficient resources are available to queue any iocbs.

       EBADF  The file descriptor specified in the first iocb is invalid.

       EFAULT One of the data structures points to invalid data.

       EINVAL The AIO context specified by ctx_id is invalid.  nr is less than 0.  The iocb at *iocbpp[0] is  not  properly  initialized,  or  the
	      operation specified is invalid for the file descriptor in the iocb.

       ENOSYS io_submit() is not implemented on this architecture.

VERSIONS

       The asynchronous I/O system calls first appeared in Linux 2.5.

CONFORMING TO

       io_submit() is Linux-specific and should not be used in programs that are intended to be portable.

NOTES

       Glibc  does  not provide a wrapper function for this system call.  You could invoke it using syscall(2).  But instead, you probably want to
       use the io_submit() wrapper function provided by libaio.

       Note that the libaio wrapper function uses a different type (io_context_t) for the ctx_id argument.  Note also that the libaio wrapper does
       not  follow  the  usual C library conventions for indicating errors: on error it returns a negated error number (the negative of one of the
       values listed in ERRORS).  If the system call is invoked via syscall(2), then the return value follows the usual conventions for indicating
       an error: -1, with errno set to a (positive) value that indicates the error.

SEE ALSO

       io_cancel(2), io_destroy(2), io_getevents(2), io_setup(2), aio(7)

COLOPHON

       This  page is part of release 3.53 of the Linux man-pages project.  A description of the project, and information about reporting bugs, can
       be found at http://www.kernel.org/doc/man-pages/.

Linux								    2012-07-13							      IO_SUBMIT(2)