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Revision 1.12 by root, Tue Aug 23 00:05:00 2005 UTC vs.
Revision 1.13 by root, Tue Aug 30 15:45:10 2005 UTC

75 are ASCII or ISO 8859-1, c) use the Encode module and encode your 75 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 76 pathnames to the locale (or other) encoding in effect in the user
77 environment, d) use Glib::filename_from_unicode on unicode filenames or 77 environment, d) use Glib::filename_from_unicode on unicode filenames or
78 e) use something else. 78 e) use something else.
79 79
80 aio_open $pathname, $flags, $mode, $callback 80 aio_open $pathname, $flags, $mode, $callback->($fh)
81 Asynchronously open or create a file and call the callback with a 81 Asynchronously open or create a file and call the callback with a
82 newly created filehandle for the file. 82 newly created filehandle for the file.
83 83
84 The pathname passed to "aio_open" must be absolute. See API NOTES, 84 The pathname passed to "aio_open" must be absolute. See API NOTES,
85 above, for an explanation. 85 above, for an explanation.
101 } else { 101 } else {
102 die "open failed: $!\n"; 102 die "open failed: $!\n";
103 } 103 }
104 }; 104 };
105 105
106 aio_close $fh, $callback 106 aio_close $fh, $callback->($status)
107 Asynchronously close a file and call the callback with the result 107 Asynchronously close a file and call the callback with the result
108 code. *WARNING:* although accepted, you should not pass in a perl 108 code. *WARNING:* although accepted, you should not pass in a perl
109 filehandle here, as perl will likely close the file descriptor 109 filehandle here, as perl will likely close the file descriptor
110 another time when the filehandle is destroyed. Normally, you can 110 another time when the filehandle is destroyed. Normally, you can
111 safely call perls "close" or just let filehandles go out of scope. 111 safely call perls "close" or just let filehandles go out of scope.
112 112
113 This is supposed to be a bug in the API, so that might change. It's 113 This is supposed to be a bug in the API, so that might change. It's
114 therefore best to avoid this function. 114 therefore best to avoid this function.
115 115
116 aio_read $fh,$offset,$length, $data,$dataoffset,$callback 116 aio_read $fh,$offset,$length, $data,$dataoffset, $callback->($retval)
117 aio_write $fh,$offset,$length, $data,$dataoffset,$callback 117 aio_write $fh,$offset,$length, $data,$dataoffset, $callback->($retval)
118 Reads or writes "length" bytes from the specified "fh" and "offset" 118 Reads or writes "length" bytes from the specified "fh" and "offset"
119 into the scalar given by "data" and offset "dataoffset" and calls 119 into the scalar given by "data" and offset "dataoffset" and calls
120 the callback without the actual number of bytes read (or -1 on 120 the callback without the actual number of bytes read (or -1 on
121 error, just like the syscall). 121 error, just like the syscall).
122 122
130 aio_read $fh, 7, 15, $buffer, 0, sub { 130 aio_read $fh, 7, 15, $buffer, 0, sub {
131 $_[0] > 0 or die "read error: $!"; 131 $_[0] > 0 or die "read error: $!";
132 print "read $_[0] bytes: <$buffer>\n"; 132 print "read $_[0] bytes: <$buffer>\n";
133 }; 133 };
134 134
135 aio_sendfile $out_fh, $in_fh, $in_offset, $length, $callback 135 aio_sendfile $out_fh, $in_fh, $in_offset, $length, $callback->($retval)
136 Tries to copy $length bytes from $in_fh to $out_fh. It starts 136 Tries to copy $length bytes from $in_fh to $out_fh. It starts
137 reading at byte offset $in_offset, and starts writing at the current 137 reading at byte offset $in_offset, and starts writing at the current
138 file offset of $out_fh. Because of that, it is not safe to issue 138 file offset of $out_fh. Because of that, it is not safe to issue
139 more than one "aio_sendfile" per $out_fh, as they will interfere 139 more than one "aio_sendfile" per $out_fh, as they will interfere
140 with each other. 140 with each other.
152 bytes have been read from "aio_sendfile" alone, as "aio_sendfile" 152 bytes have been read from "aio_sendfile" alone, as "aio_sendfile"
153 only provides the number of bytes written to $out_fh. Only if the 153 only provides the number of bytes written to $out_fh. Only if the
154 result value equals $length one can assume that $length bytes have 154 result value equals $length one can assume that $length bytes have
155 been read. 155 been read.
156 156
157 aio_readahead $fh,$offset,$length, $callback 157 aio_readahead $fh,$offset,$length, $callback->($retval)
158 "aio_readahead" populates the page cache with data from a file so 158 "aio_readahead" populates the page cache with data from a file so
159 that subsequent reads from that file will not block on disk I/O. The 159 that subsequent reads from that file will not block on disk I/O. The
160 $offset argument specifies the starting point from which data is to 160 $offset argument specifies the starting point from which data is to
161 be read and $length specifies the number of bytes to be read. I/O is 161 be read and $length specifies the number of bytes to be read. I/O is
162 performed in whole pages, so that offset is effectively rounded down 162 performed in whole pages, so that offset is effectively rounded down
167 167
168 If that syscall doesn't exist (likely if your OS isn't Linux) it 168 If that syscall doesn't exist (likely if your OS isn't Linux) it
169 will be emulated by simply reading the data, which would have a 169 will be emulated by simply reading the data, which would have a
170 similar effect. 170 similar effect.
171 171
172 aio_stat $fh_or_path, $callback 172 aio_stat $fh_or_path, $callback->($status)
173 aio_lstat $fh, $callback 173 aio_lstat $fh, $callback->($status)
174 Works like perl's "stat" or "lstat" in void context. The callback 174 Works like perl's "stat" or "lstat" in void context. The callback
175 will be called after the stat and the results will be available 175 will be called after the stat and the results will be available
176 using "stat _" or "-s _" etc... 176 using "stat _" or "-s _" etc...
177 177
178 The pathname passed to "aio_stat" must be absolute. See API NOTES, 178 The pathname passed to "aio_stat" must be absolute. See API NOTES,
188 aio_stat "/etc/passwd", sub { 188 aio_stat "/etc/passwd", sub {
189 $_[0] and die "stat failed: $!"; 189 $_[0] and die "stat failed: $!";
190 print "size is ", -s _, "\n"; 190 print "size is ", -s _, "\n";
191 }; 191 };
192 192
193 aio_unlink $pathname, $callback 193 aio_unlink $pathname, $callback->($status)
194 Asynchronously unlink (delete) a file and call the callback with the 194 Asynchronously unlink (delete) a file and call the callback with the
195 result code. 195 result code.
196 196
197 aio_rmdir $pathname, $callback 197 aio_rmdir $pathname, $callback->($status)
198 Asynchronously rmdir (delete) a directory and call the callback with 198 Asynchronously rmdir (delete) a directory and call the callback with
199 the result code. 199 the result code.
200 200
201 aio_readdir $pathname $callback->($entries)
202 Unlike the POSIX call of the same name, "aio_readdir" reads an
203 entire directory (i.e. opendir + readdir + closedir). The entries
204 will not be sorted, and will NOT include the "." and ".." entries.
205
206 The callback a single argument which is either "undef" or an
207 array-ref with the filenames.
208
209 aio_scandir $path, $maxreq, $callback->($dirs, $nondirs)
210 Scans a directory (similar to "aio_readdir") and tries to separate
211 the entries of directory $path into two sets of names, ones you can
212 recurse into (directories), and ones you cannot recurse into
213 (everything else).
214
215 "aio_scandir" is a composite request that consists of many
216 aio-primitives. $maxreq specifies the maximum number of outstanding
217 aio requests that this function generates. If it is "<= 0", then a
218 suitable default will be chosen (currently 8).
219
220 On error, the callback is called without arguments, otherwise it
221 receives two array-refs with path-relative entry names.
222
223 Example:
224
225 aio_scandir $dir, 0, sub {
226 my ($dirs, $nondirs) = @_;
227 print "real directories: @$dirs\n";
228 print "everything else: @$nondirs\n";
229 };
230
231 Implementation notes.
232
233 The "aio_readdir" cannot be avoided, but "stat()"'ing every entry
234 can.
235
236 After reading the directory, the modification time, size etc. of the
237 directory before and after the readdir is checked, and if they
238 match, the link count will be used to decide how many entries are
239 directories (if >= 2). Otherwise, no knowledge of the number of
240 subdirectories will be assumed.
241
242 Then entires will be sorted into likely directories (everything
243 without a non-initial dot) and likely non-directories (everything
244 else). Then every entry + "/." will be "stat"'ed, likely directories
245 first. This is often faster because filesystems might detect the
246 type of the entry without reading the inode data (e.g. ext2s
247 filetype feature). If that succeeds, it assumes that the entry is a
248 directory or a symlink to directory (which will be checked
249 seperately).
250
251 If the known number of directories has been reached, the rest of the
252 entries is assumed to be non-directories.
253
201 aio_fsync $fh, $callback 254 aio_fsync $fh, $callback->($status)
202 Asynchronously call fsync on the given filehandle and call the 255 Asynchronously call fsync on the given filehandle and call the
203 callback with the fsync result code. 256 callback with the fsync result code.
204 257
205 aio_fdatasync $fh, $callback 258 aio_fdatasync $fh, $callback->($status)
206 Asynchronously call fdatasync on the given filehandle and call the 259 Asynchronously call fdatasync on the given filehandle and call the
207 callback with the fdatasync result code. 260 callback with the fdatasync result code.
208 261
209 If this call isn't available because your OS lacks it or it couldn't 262 If this call isn't available because your OS lacks it or it couldn't
210 be detected, it will be emulated by calling "fsync" instead. 263 be detected, it will be emulated by calling "fsync" instead.

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