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Revision 1.11 by root, Sat Aug 20 00:32:42 2005 UTC vs.
Revision 1.16 by root, Wed Mar 1 23:56:55 2006 UTC

… …
12 aio_unlink "/tmp/file", sub { }; 12 aio_unlink "/tmp/file", sub { };
13 13
14 aio_read $fh, 30000, 1024, $buffer, 0, sub { 14 aio_read $fh, 30000, 1024, $buffer, 0, sub {
15 $_[0] > 0 or die "read error: $!"; 15 $_[0] > 0 or die "read error: $!";
16 }; 16 };
17
18 # AnyEvent
19 open my $fh, "<&=" . IO::AIO::poll_fileno or die "$!";
20 my $w = AnyEvent->io (fh => $fh, poll => 'r', cb => sub { IO::AIO::poll_cb });
17 21
18 # Event 22 # Event
19 Event->io (fd => IO::AIO::poll_fileno, 23 Event->io (fd => IO::AIO::poll_fileno,
20 poll => 'r', 24 poll => 'r',
21 cb => \&IO::AIO::poll_cb); 25 cb => \&IO::AIO::poll_cb);
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75 are ASCII or ISO 8859-1, c) use the Encode module and encode your 79 are ASCII or ISO 8859-1, c) use the Encode module and encode your
76 pathnames to the locale (or other) encoding in effect in the user 80 pathnames to the locale (or other) encoding in effect in the user
77 environment, d) use Glib::filename_from_unicode on unicode filenames or 81 environment, d) use Glib::filename_from_unicode on unicode filenames or
78 e) use something else. 82 e) use something else.
79 83
80 aio_open $pathname, $flags, $mode, $callback 84 aio_open $pathname, $flags, $mode, $callback->($fh)
81 Asynchronously open or create a file and call the callback with a 85 Asynchronously open or create a file and call the callback with a
82 newly created filehandle for the file. 86 newly created filehandle for the file.
83 87
84 The pathname passed to "aio_open" must be absolute. See API NOTES, 88 The pathname passed to "aio_open" must be absolute. See API NOTES,
85 above, for an explanation. 89 above, for an explanation.
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101 } else { 105 } else {
102 die "open failed: $!\n"; 106 die "open failed: $!\n";
103 } 107 }
104 }; 108 };
105 109
106 aio_close $fh, $callback 110 aio_close $fh, $callback->($status)
107 Asynchronously close a file and call the callback with the result 111 Asynchronously close a file and call the callback with the result
108 code. *WARNING:* although accepted, you should not pass in a perl 112 code. *WARNING:* although accepted, you should not pass in a perl
109 filehandle here, as perl will likely close the file descriptor 113 filehandle here, as perl will likely close the file descriptor
110 another time when the filehandle is destroyed. Normally, you can 114 another time when the filehandle is destroyed. Normally, you can
111 safely call perls "close" or just let filehandles go out of scope. 115 safely call perls "close" or just let filehandles go out of scope.
112 116
113 This is supposed to be a bug in the API, so that might change. It's 117 This is supposed to be a bug in the API, so that might change. It's
114 therefore best to avoid this function. 118 therefore best to avoid this function.
115 119
116 aio_read $fh,$offset,$length, $data,$dataoffset,$callback 120 aio_read $fh,$offset,$length, $data,$dataoffset, $callback->($retval)
117 aio_write $fh,$offset,$length, $data,$dataoffset,$callback 121 aio_write $fh,$offset,$length, $data,$dataoffset, $callback->($retval)
118 Reads or writes "length" bytes from the specified "fh" and "offset" 122 Reads or writes "length" bytes from the specified "fh" and "offset"
119 into the scalar given by "data" and offset "dataoffset" and calls 123 into the scalar given by "data" and offset "dataoffset" and calls
120 the callback without the actual number of bytes read (or -1 on 124 the callback without the actual number of bytes read (or -1 on
121 error, just like the syscall). 125 error, just like the syscall).
122 126
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130 aio_read $fh, 7, 15, $buffer, 0, sub { 134 aio_read $fh, 7, 15, $buffer, 0, sub {
131 $_[0] > 0 or die "read error: $!"; 135 $_[0] > 0 or die "read error: $!";
132 print "read $_[0] bytes: <$buffer>\n"; 136 print "read $_[0] bytes: <$buffer>\n";
133 }; 137 };
134 138
139 aio_sendfile $out_fh, $in_fh, $in_offset, $length, $callback->($retval)
140 Tries to copy $length bytes from $in_fh to $out_fh. It starts
141 reading at byte offset $in_offset, and starts writing at the current
142 file offset of $out_fh. Because of that, it is not safe to issue
143 more than one "aio_sendfile" per $out_fh, as they will interfere
144 with each other.
145
146 This call tries to make use of a native "sendfile" syscall to
147 provide zero-copy operation. For this to work, $out_fh should refer
148 to a socket, and $in_fh should refer to mmap'able file.
149
150 If the native sendfile call fails or is not implemented, it will be
151 emulated, so you can call "aio_sendfile" on any type of filehandle
152 regardless of the limitations of the operating system.
153
154 Please note, however, that "aio_sendfile" can read more bytes from
155 $in_fh than are written, and there is no way to find out how many
156 bytes have been read from "aio_sendfile" alone, as "aio_sendfile"
157 only provides the number of bytes written to $out_fh. Only if the
158 result value equals $length one can assume that $length bytes have
159 been read.
160
135 aio_readahead $fh,$offset,$length, $callback 161 aio_readahead $fh,$offset,$length, $callback->($retval)
136 "aio_readahead" populates the page cache with data from a file so 162 "aio_readahead" populates the page cache with data from a file so
137 that subsequent reads from that file will not block on disk I/O. The 163 that subsequent reads from that file will not block on disk I/O. The
138 $offset argument specifies the starting point from which data is to 164 $offset argument specifies the starting point from which data is to
139 be read and $length specifies the number of bytes to be read. I/O is 165 be read and $length specifies the number of bytes to be read. I/O is
140 performed in whole pages, so that offset is effectively rounded down 166 performed in whole pages, so that offset is effectively rounded down
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145 171
146 If that syscall doesn't exist (likely if your OS isn't Linux) it 172 If that syscall doesn't exist (likely if your OS isn't Linux) it
147 will be emulated by simply reading the data, which would have a 173 will be emulated by simply reading the data, which would have a
148 similar effect. 174 similar effect.
149 175
150 aio_stat $fh_or_path, $callback 176 aio_stat $fh_or_path, $callback->($status)
151 aio_lstat $fh, $callback 177 aio_lstat $fh, $callback->($status)
152 Works like perl's "stat" or "lstat" in void context. The callback 178 Works like perl's "stat" or "lstat" in void context. The callback
153 will be called after the stat and the results will be available 179 will be called after the stat and the results will be available
154 using "stat _" or "-s _" etc... 180 using "stat _" or "-s _" etc...
155 181
156 The pathname passed to "aio_stat" must be absolute. See API NOTES, 182 The pathname passed to "aio_stat" must be absolute. See API NOTES,
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166 aio_stat "/etc/passwd", sub { 192 aio_stat "/etc/passwd", sub {
167 $_[0] and die "stat failed: $!"; 193 $_[0] and die "stat failed: $!";
168 print "size is ", -s _, "\n"; 194 print "size is ", -s _, "\n";
169 }; 195 };
170 196
171 aio_unlink $pathname, $callback 197 aio_unlink $pathname, $callback->($status)
172 Asynchronously unlink (delete) a file and call the callback with the 198 Asynchronously unlink (delete) a file and call the callback with the
173 result code. 199 result code.
174 200
175 aio_rmdir $pathname, $callback 201 aio_rmdir $pathname, $callback->($status)
176 Asynchronously rmdir (delete) a directory and call the callback with 202 Asynchronously rmdir (delete) a directory and call the callback with
177 the result code. 203 the result code.
178 204
205 aio_readdir $pathname, $callback->($entries)
206 Unlike the POSIX call of the same name, "aio_readdir" reads an
207 entire directory (i.e. opendir + readdir + closedir). The entries
208 will not be sorted, and will NOT include the "." and ".." entries.
209
210 The callback a single argument which is either "undef" or an
211 array-ref with the filenames.
212
213 aio_scandir $path, $maxreq, $callback->($dirs, $nondirs)
214 Scans a directory (similar to "aio_readdir") and tries to separate
215 the entries of directory $path into two sets of names, ones you can
216 recurse into (directories), and ones you cannot recurse into
217 (everything else).
218
219 "aio_scandir" is a composite request that consists of many
220 aio-primitives. $maxreq specifies the maximum number of outstanding
221 aio requests that this function generates. If it is "<= 0", then a
222 suitable default will be chosen (currently 8).
223
224 On error, the callback is called without arguments, otherwise it
225 receives two array-refs with path-relative entry names.
226
227 Example:
228
229 aio_scandir $dir, 0, sub {
230 my ($dirs, $nondirs) = @_;
231 print "real directories: @$dirs\n";
232 print "everything else: @$nondirs\n";
233 };
234
235 Implementation notes.
236
237 The "aio_readdir" cannot be avoided, but "stat()"'ing every entry
238 can.
239
240 After reading the directory, the modification time, size etc. of the
241 directory before and after the readdir is checked, and if they
242 match, the link count will be used to decide how many entries are
243 directories (if >= 2). Otherwise, no knowledge of the number of
244 subdirectories will be assumed.
245
246 Then entires will be sorted into likely directories (everything
247 without a non-initial dot) and likely non-directories (everything
248 else). Then every entry + "/." will be "stat"'ed, likely directories
249 first. This is often faster because filesystems might detect the
250 type of the entry without reading the inode data (e.g. ext2fs
251 filetype feature). If that succeeds, it assumes that the entry is a
252 directory or a symlink to directory (which will be checked
253 seperately).
254
255 If the known number of directories has been reached, the rest of the
256 entries is assumed to be non-directories.
257
179 aio_fsync $fh, $callback 258 aio_fsync $fh, $callback->($status)
180 Asynchronously call fsync on the given filehandle and call the 259 Asynchronously call fsync on the given filehandle and call the
181 callback with the fsync result code. 260 callback with the fsync result code.
182 261
183 aio_fdatasync $fh, $callback 262 aio_fdatasync $fh, $callback->($status)
184 Asynchronously call fdatasync on the given filehandle and call the 263 Asynchronously call fdatasync on the given filehandle and call the
185 callback with the fdatasync result code. 264 callback with the fdatasync result code.
186 265
187 If this call isn't available because your OS lacks it or it couldn't 266 If this call isn't available because your OS lacks it or it couldn't
188 be detected, it will be emulated by calling "fsync" instead. 267 be detected, it will be emulated by calling "fsync" instead.

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