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Revision: 1.6
Committed: Thu Aug 30 03:12:54 2001 UTC (22 years, 8 months ago) by root
Branch: MAIN
Changes since 1.5: +2 -0 lines
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# User Rev Content
1 root 1.1 =head1 NAME
2    
3     Linux::AIO - linux-specific aio implemented using clone
4    
5     =head1 SYNOPSIS
6    
7     use Linux::AIO;
8    
9     =head1 DESCRIPTION
10    
11 root 1.3 This module implements asynchroneous i/o using the means available to
12     linux - clone. It does not hook into the POSIX aio_* functions because
13     linux does not yet support these in the kernel. Instead, a number of
14     threads are started that execute your read/writes and signal their
15     completion.
16    
17 root 1.1 =over 4
18    
19     =cut
20    
21     package Linux::AIO;
22    
23 root 1.2 use base 'Exporter';
24    
25 root 1.1 BEGIN {
26 root 1.4 $VERSION = 0.002;
27 root 1.1
28 root 1.5 @EXPORT = qw(aio_read aio_write aio_open aio_close);
29 root 1.2 @EXPORT_OK = qw(poll_fileno poll_cb min_parallel max_parallel nreqs);
30    
31 root 1.1 require XSLoader;
32     XSLoader::load Linux::AIO, $VERSION;
33     }
34    
35     =item Linux::AIO::min_parallel($nthreads)
36    
37 root 1.3 Set the minimum number of AIO threads to $nthreads. You I<have> to call
38     this function with a positive number at leats once, otherwise no threads
39     will be started and you aio-operations will seem to hang.
40 root 1.1
41 root 1.2 =item $fileno = Linux::AIO::poll_fileno
42    
43     Return the request result pipe filehandle. This filehandle must be polled
44     for reading. If the pipe becomes readable you have to call C<poll_cb>.
45    
46     =item Linux::AIO::poll_cb
47    
48     Process all outstanding events on the result pipe. You have to call this
49     regularly. Returns the number of events processed.
50    
51 root 1.3 You can use Event to multiplex, e.g.:
52    
53     Event->io(fd => Linux::AIO::poll_fileno,
54     poll => 'r', async => 1,
55     cb => \&Linux::AIO::poll_cb );
56    
57    
58 root 1.2 =item Linux::AIO::nreqs
59    
60     Returns the number of requests currently outstanding.
61 root 1.4
62     =item aio_read($fh,$offset,$length, $data,$dataoffset,$callback)
63     aio_write($fh,$offset,$length, $data,$dataoffset,$callback)
64    
65     Reads or writes C<length> bytes from the specified C<fh> and C<offset>
66     into the scalar given by C<data> and offset C<dataoffset> and calls the
67     callback without the actual number of bytes read (or undef on error).
68    
69     =item aio_open($pathname, $flags, $mode, $callback)
70    
71     Asynchronously open or create a file and call the callback with the
72     filedescriptor.
73 root 1.5
74     =item aio_close($fh, $callback)
75    
76     Asynchronously close a file and call the callback with the result code.
77 root 1.2
78 root 1.1 =cut
79 root 1.2
80     END {
81     max_parallel 0;
82     }
83 root 1.1
84     1;
85    
86     =back
87    
88     =head1 BUGS
89    
90     This module has not yet been extensively tested. Watch out!
91    
92 root 1.6 - aio_stat/lstat are seriously missing here.
93    
94 root 1.1 =head1 SEE ALSO
95    
96     L<Coro>.
97    
98     =head1 AUTHOR
99    
100     Marc Lehmann <pcg@goof.com>
101     http://www.goof.com/pcg/marc/
102    
103     =cut
104