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Revision 1.11 by root, Sat Aug 20 00:32:42 2005 UTC vs.
Revision 1.17 by root, Mon Jun 26 14:53:55 2006 UTC

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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_move $srcpath, $dstpath, $callback->($status)
140 [EXPERIMENTAL]
141
142 Try to move the *file* (directories not supported as either source
143 or destination) from $srcpath to $dstpath and call the callback with
144 the 0 (error) or -1 ok.
145
146 This is a composite request that tries to rename(2) the file first.
147 If rename files with "EXDEV", it creates the destination file with
148 mode 0200 and copies the contents of the source file into it using
149 "aio_sendfile", followed by restoring atime, mtime, access mode and
150 uid/gid, in that order, and unlinking the $srcpath.
151
152 If an error occurs, the partial destination file will be unlinked,
153 if possible, except when setting atime, mtime, access mode and
154 uid/gid, where errors are being ignored.
155
156 aio_sendfile $out_fh, $in_fh, $in_offset, $length, $callback->($retval)
157 Tries to copy $length bytes from $in_fh to $out_fh. It starts
158 reading at byte offset $in_offset, and starts writing at the current
159 file offset of $out_fh. Because of that, it is not safe to issue
160 more than one "aio_sendfile" per $out_fh, as they will interfere
161 with each other.
162
163 This call tries to make use of a native "sendfile" syscall to
164 provide zero-copy operation. For this to work, $out_fh should refer
165 to a socket, and $in_fh should refer to mmap'able file.
166
167 If the native sendfile call fails or is not implemented, it will be
168 emulated, so you can call "aio_sendfile" on any type of filehandle
169 regardless of the limitations of the operating system.
170
171 Please note, however, that "aio_sendfile" can read more bytes from
172 $in_fh than are written, and there is no way to find out how many
173 bytes have been read from "aio_sendfile" alone, as "aio_sendfile"
174 only provides the number of bytes written to $out_fh. Only if the
175 result value equals $length one can assume that $length bytes have
176 been read.
177
135 aio_readahead $fh,$offset,$length, $callback 178 aio_readahead $fh,$offset,$length, $callback->($retval)
136 "aio_readahead" populates the page cache with data from a file so 179 "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 180 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 181 $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 182 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 183 performed in whole pages, so that offset is effectively rounded down
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145 188
146 If that syscall doesn't exist (likely if your OS isn't Linux) it 189 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 190 will be emulated by simply reading the data, which would have a
148 similar effect. 191 similar effect.
149 192
150 aio_stat $fh_or_path, $callback 193 aio_stat $fh_or_path, $callback->($status)
151 aio_lstat $fh, $callback 194 aio_lstat $fh, $callback->($status)
152 Works like perl's "stat" or "lstat" in void context. The callback 195 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 196 will be called after the stat and the results will be available
154 using "stat _" or "-s _" etc... 197 using "stat _" or "-s _" etc...
155 198
156 The pathname passed to "aio_stat" must be absolute. See API NOTES, 199 The pathname passed to "aio_stat" must be absolute. See API NOTES,
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166 aio_stat "/etc/passwd", sub { 209 aio_stat "/etc/passwd", sub {
167 $_[0] and die "stat failed: $!"; 210 $_[0] and die "stat failed: $!";
168 print "size is ", -s _, "\n"; 211 print "size is ", -s _, "\n";
169 }; 212 };
170 213
171 aio_unlink $pathname, $callback 214 aio_unlink $pathname, $callback->($status)
172 Asynchronously unlink (delete) a file and call the callback with the 215 Asynchronously unlink (delete) a file and call the callback with the
173 result code. 216 result code.
174 217
218 aio_link $srcpath, $dstpath, $callback->($status)
219 Asynchronously create a new link to the existing object at $srcpath
220 at the path $dstpath and call the callback with the result code.
221
222 aio_symlink $srcpath, $dstpath, $callback->($status)
223 Asynchronously create a new symbolic link to the existing object at
224 $srcpath at the path $dstpath and call the callback with the result
225 code.
226
227 aio_rename $srcpath, $dstpath, $callback->($status)
228 Asynchronously rename the object at $srcpath to $dstpath, just as
229 rename(2) and call the callback with the result code.
230
175 aio_rmdir $pathname, $callback 231 aio_rmdir $pathname, $callback->($status)
176 Asynchronously rmdir (delete) a directory and call the callback with 232 Asynchronously rmdir (delete) a directory and call the callback with
177 the result code. 233 the result code.
178 234
235 aio_readdir $pathname, $callback->($entries)
236 Unlike the POSIX call of the same name, "aio_readdir" reads an
237 entire directory (i.e. opendir + readdir + closedir). The entries
238 will not be sorted, and will NOT include the "." and ".." entries.
239
240 The callback a single argument which is either "undef" or an
241 array-ref with the filenames.
242
243 aio_scandir $path, $maxreq, $callback->($dirs, $nondirs)
244 Scans a directory (similar to "aio_readdir") and tries to separate
245 the entries of directory $path into two sets of names, ones you can
246 recurse into (directories), and ones you cannot recurse into
247 (everything else).
248
249 "aio_scandir" is a composite request that consists of many
250 aio-primitives. $maxreq specifies the maximum number of outstanding
251 aio requests that this function generates. If it is "<= 0", then a
252 suitable default will be chosen (currently 8).
253
254 On error, the callback is called without arguments, otherwise it
255 receives two array-refs with path-relative entry names.
256
257 Example:
258
259 aio_scandir $dir, 0, sub {
260 my ($dirs, $nondirs) = @_;
261 print "real directories: @$dirs\n";
262 print "everything else: @$nondirs\n";
263 };
264
265 Implementation notes.
266
267 The "aio_readdir" cannot be avoided, but "stat()"'ing every entry
268 can.
269
270 After reading the directory, the modification time, size etc. of the
271 directory before and after the readdir is checked, and if they
272 match, the link count will be used to decide how many entries are
273 directories (if >= 2). Otherwise, no knowledge of the number of
274 subdirectories will be assumed.
275
276 Then entires will be sorted into likely directories (everything
277 without a non-initial dot) and likely non-directories (everything
278 else). Then every entry + "/." will be "stat"'ed, likely directories
279 first. This is often faster because filesystems might detect the
280 type of the entry without reading the inode data (e.g. ext2fs
281 filetype feature). If that succeeds, it assumes that the entry is a
282 directory or a symlink to directory (which will be checked
283 seperately).
284
285 If the known number of directories has been reached, the rest of the
286 entries is assumed to be non-directories.
287
179 aio_fsync $fh, $callback 288 aio_fsync $fh, $callback->($status)
180 Asynchronously call fsync on the given filehandle and call the 289 Asynchronously call fsync on the given filehandle and call the
181 callback with the fsync result code. 290 callback with the fsync result code.
182 291
183 aio_fdatasync $fh, $callback 292 aio_fdatasync $fh, $callback->($status)
184 Asynchronously call fdatasync on the given filehandle and call the 293 Asynchronously call fdatasync on the given filehandle and call the
185 callback with the fdatasync result code. 294 callback with the fdatasync result code.
186 295
187 If this call isn't available because your OS lacks it or it couldn't 296 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. 297 be detected, it will be emulated by calling "fsync" instead.

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