=encoding utf8 =head1 NAME Mail::Box::File - handle file-based folders =head1 INHERITANCE Mail::Box::File is a Mail::Box is a Mail::Reporter Mail::Box::File is extended by Mail::Box::Dbx Mail::Box::Mbox =head1 SYNOPSIS =head1 DESCRIPTION C is the base-class for all file-based folders: folders which bundle multiple messages into one single file. Usually, these messages are separated by a special line which indicates the start of the next one. Extends L<"DESCRIPTION" in Mail::Box|Mail::Box/"DESCRIPTION">. =head1 OVERLOADED Extends L<"OVERLOADED" in Mail::Box|Mail::Box/"OVERLOADED">. =over 4 =item overload: B<""> Inherited, see L =item overload: B<@{}> Inherited, see L =item overload: B Inherited, see L =back =head1 METHODS Extends L<"METHODS" in Mail::Box|Mail::Box/"METHODS">. =head2 Constructors Extends L<"Constructors" in Mail::Box|Mail::Box/"Constructors">. =over 4 =item Mail::Box::File-EB(%options) -Option --Defined in --Default access Mail::Box 'r' body_delayed_type Mail::Box Mail::Message::Body::Delayed body_type coerce_options Mail::Box [] create Mail::Box extract Mail::Box 10240 field_type Mail::Box undef fix_headers Mail::Box folder Mail::Box $ENV{MAIL} folderdir Mail::Box $ENV{HOME}.'/Mail' head_delayed_type Mail::Box Mail::Message::Head::Delayed head_type Mail::Box Mail::Message::Head::Complete keep_dups Mail::Box lock_extension '.lock' lock_file Mail::Box lock_timeout Mail::Box 1 hour lock_type Mail::Box Mail::Box::Locker::DotLock lock_wait Mail::Box 10 seconds locker Mail::Box undef log Mail::Reporter 'WARNINGS' manager Mail::Box undef message_type Mail::Box Mail::Box::File::Message multipart_type Mail::Box Mail::Message::Body::Multipart remove_when_empty Mail::Box save_on_exit Mail::Box trace Mail::Reporter 'WARNINGS' trusted Mail::Box write_policy undef =over 2 =item access => MODE =item body_delayed_type => CLASS =item body_type => CLASS|CODE The default C option for C folders, which will cause messages larger than 10kB to be stored in files and smaller files in memory, is implemented like this: sub determine_body_type($$) { my $head = shift; my $size = shift || 0; 'Mail::Message::Body::' . ($size > 10000 ? 'File' : 'Lines'); } =item coerce_options => ARRAY =item create => BOOLEAN =item extract => INTEGER | CODE | METHOD | 'LAZY'|'ALWAYS' =item field_type => CLASS =item fix_headers => BOOLEAN =item folder => FOLDERNAME =item folderdir => DIRECTORY =item head_delayed_type => CLASS =item head_type => CLASS =item keep_dups => BOOLEAN =item lock_extension => FILENAME|STRING When the dotlock locking mechanism is used, the lock is created with a hardlink to the folder file. For C type of folders, this file is by default named as the folder-file itself followed by C<.lock>. For example: the C folder file will have a hardlink made as C. You may specify an absolute filename, a relative (to the folder's directory) filename, or an extension (preceded by a dot). So valid examples are: .lock # appended to the folder's filename my_own_lockfile.test # full filename, same dir /etc/passwd # somewhere else When the program runs with less privileges (as normal user), often the default inbox folder can not be locked with the lockfile name which is produced by default. =item lock_file => FILENAME =item lock_timeout => SECONDS =item lock_type => CLASS|STRING|ARRAY =item lock_wait => SECONDS =item locker => OBJECT =item log => LEVEL =item manager => MANAGER =item message_type => CLASS =item multipart_type => CLASS =item remove_when_empty => BOOLEAN =item save_on_exit => BOOLEAN =item trace => LEVEL =item trusted => BOOLEAN =item write_policy => 'REPLACE'|'INPLACE'|undef Sets the default write policy, as default for a later call to L. With C, the best policy is autodetected. =back =back =head2 The folder Extends L<"The folder" in Mail::Box|Mail::Box/"The folder">. =over 4 =item $obj-EB($message, %options) Inherited, see L =item $obj-EB(@messages) Inherited, see L =item Mail::Box::File-EB(%options) Appending messages to a file based folder which is not opened is a little risky. In practice, this is often done without locking the folder. So, another application may write to the folder at the same time... :( Hopefully, all goes fast enough that the chance on collision is small. All %options of L can be supplied. -Option --Defined in --Default folder Mail::Box lock_type NONE message Mail::Box undef messages Mail::Box undef share Mail::Box =over 2 =item folder => FOLDERNAME =item lock_type => ... See L for possible values. =item message => MESSAGE =item messages => ARRAY-OF-MESSAGES =item share => BOOLEAN =back =item $obj-EB(%options) Inherited, see L =item $obj-EB($folder, %options) Inherited, see L =item $obj-EB(%options) Inherited, see L =item $obj-EB() Returns the filename for this folder, which may be an absolute or relative path to the file. example: print $folder->filename; =item $obj-EB( [$directory] ) Inherited, see L =item $obj-EB() Inherited, see L =item $obj-EB() Inherited, see L =item $obj-EB() Inherited, see L =item $obj-EB() Inherited, see L =item $obj-EB(%options) Inherited, see L =item $obj-EB() Inherited, see L =back =head2 Folder flags Extends L<"Folder flags" in Mail::Box|Mail::Box/"Folder flags">. =over 4 =item $obj-EB() Inherited, see L =item $obj-EB() Inherited, see L =item $obj-EB( [BOOLEAN] ) Inherited, see L =item $obj-EB() Inherited, see L =back =head2 The messages Extends L<"The messages" in Mail::Box|Mail::Box/"The messages">. =over 4 =item $obj-EB( [$number|$message|$message_id] ) Inherited, see L =item $obj-EB($message_id) Inherited, see L =item $obj-EB( $label, [BOOLEAN, [$msgs]] ) Inherited, see L =item $obj-EB( $index, [$message] ) Inherited, see L =item $obj-EB( $message_id, [$message] ) Inherited, see L =item $obj-EB() Inherited, see L =item $obj-EB( <'ALL'|$range|'ACTIVE'|'DELETED'|$label| !$label|$filter> ) Inherited, see L =item $obj-EB(%options) Inherited, see L =item $obj-EB($message, $message_ids, $timespan, $window) Inherited, see L =back =head2 Sub-folders Extends L<"Sub-folders" in Mail::Box|Mail::Box/"Sub-folders">. =over 4 =item $obj-EB(%options) =item Mail::Box::File-EB(%options) Inherited, see L =item $obj-EB( $subname, [$parentname] ) =item Mail::Box::File-EB( $subname, [$parentname] ) Inherited, see L =item $obj-EB(%options) Inherited, see L =item $obj-EB($subname, %options) Inherited, see L =item $obj-EB() =item Mail::Box::File-EB() Inherited, see L =back =head2 Internals Extends L<"Internals" in Mail::Box|Mail::Box/"Internals">. =over 4 =item $obj-EB($message, %options) Inherited, see L =item $obj-EB($foldername, %options) =item Mail::Box::File-EB($foldername, %options) -Option --Defined in--Default folderdir Mail::Box undef =over 2 =item folderdir => DIRECTORY =back =item $obj-EB($message, $head) Inherited, see L =item $obj-EB( $foldername, $folderdir, [$subext] ) =item Mail::Box::File-EB( $foldername, $folderdir, [$subext] ) Translate a folder name into a filename, using the $folderdir value to replace a leading C<=>. $subext is only used for MBOX folders. =item Mail::Box::File-EB( [$foldername], %options ) Inherited, see L =item $obj-EB( [] ) Inherited, see L =item $obj-EB() Inherited, see L =item $obj-EB( [$type, $config] ) Returns a key-value list of options to be used each time a new message is read from a file. The list is preceded by the $type of message which has to be created. This data is used by L and L. With $type and $config, a new configuration is set. =item $obj-EB($directory, $extension) The $directory is renamed by appending the $extension, which defaults to C<".d">, to make place for a folder file on that specific location. C is returned if this failed. =item $obj-EB() Create a parser for this mailbox. The parser stays alive as long as the folder is open. =item $obj-EB(%options) Inherited, see L =item $obj-EB(%options) Inherited, see L =item $obj-EB($message) Inherited, see L =item $obj-EB($messages) Inherited, see L =item $obj-EB($messages) Inherited, see L =item $obj-EB(%options) For file based folders, the file handle stays open until the folder is closed. Update is therefore rather simple: move to the end of the last known message, and continue reading... =item $obj-EB(%options) -Option --Defined in --Default force Mail::Box policy undef save_deleted Mail::Box =over 2 =item force => BOOLEAN =item policy => 'REPLACE'|'INPLACE'|undef In what way will the mail folder be updated. If not specified during the write, the value of the L at folder creation is taken. Valid values: =over 4 =item * C First a new folder is written in the same directory as the folder which has to be updated, and then a call to move will throw away the old immediately replacing it by the new. Writing in C module is slightly optimized: messages which are not modified are copied from file to file, byte by byte. This is much faster than printing the data which is will be done for modified messages. =item * C The original folder file will be opened read/write. All message which where not changed will be left untouched, until the first deleted or modified message is detected. All further messages are printed again. =item * C As default, or when C is explicitly specified, first C mode is tried. Only when that fails, an C update is performed. =back C will be much faster than C when applied on large folders, however requires the C function to be implemented on your operating system (at least available for recent versions of Linux, Solaris, Tru64, HPUX). It is also dangerous: when the program is interrupted during the update process, the folder is corrupted. Data may be lost. However, in some cases it is not possible to write the folder with C. For instance, the usual incoming mail folder on UNIX is stored in a directory where a user can not write. Of course, the C and C users can, but if you want to use this Perl module with permission of a normal user, you can only get it to work in C mode. Be warned that in this case folder locking via a lockfile is not possible as well. =item save_deleted => BOOLEAN =back =item $obj-EB(%options) Inherited, see L =back =head2 Other methods Extends L<"Other methods" in Mail::Box|Mail::Box/"Other methods">. =over 4 =item $obj-EB($time) =item Mail::Box::File-EB($time) Inherited, see L =back =head2 Error handling Extends L<"Error handling" in Mail::Box|Mail::Box/"Error handling">. =over 4 =item $obj-EB() Inherited, see L =item $obj-EB($object) Inherited, see L =item $obj-EB( [$level]|[$loglevel, $tracelevel]|[$level, $callback] ) =item Mail::Box::File-EB( [$level]|[$loglevel, $tracelevel]|[$level, $callback] ) Inherited, see L =item $obj-EB() Inherited, see L =item $obj-EB( [$level, [$strings]] ) =item Mail::Box::File-EB( [$level, [$strings]] ) Inherited, see L =item $obj-EB($level) =item Mail::Box::File-EB($level) Inherited, see L =item $obj-EB() Inherited, see L =item $obj-EB() Inherited, see L =item $obj-EB( [$level] ) Inherited, see L =item $obj-EB( [$level] ) Inherited, see L =item $obj-EB( [$level] ) Inherited, see L =item $obj-EB() Inherited, see L =back =head2 Cleanup Extends L<"Cleanup" in Mail::Box|Mail::Box/"Cleanup">. =over 4 =item $obj-EB() Inherited, see L =back =head2 DETAILS =head3 File based folders File based folders maintain a folder (a set of messages) in one single file. The advantage is that your folder has only one single name, which speeds-up access to all messages at once. The disadvantage over directory based folder (see L) is that you have to construct some means to keep all message apart, for instance by adding a message separator, and this will cause problems. Where access to all messages at once is faster in file based folders, access to a single message is (much) slower, because the whole folder must be read. =head1 DETAILS Extends L<"DETAILS" in Mail::Box|Mail::Box/"DETAILS">. =head1 DIAGNOSTICS =over 4 =item Error: Cannot append messages to folder file $filename: $! Appending messages to a not-opened file-organized folder may fail when the operating system does not allow write access to the file at hand. =item Error: Cannot create directory $dir for folder $name. While creating a file-organized folder, at most one level of directories is created above it. Apparently, more levels of directories are needed, or the operating system does not allow you to create the directory. =item Error: Cannot create folder file $name: $! The file-organized folder file cannot be created for the indicated reason. In common cases, the operating system does not grant you write access to the directory where the folder file should be stored. =item Error: Cannot get a lock on $type folder $self. A lock is required to get access to the folder. If no locking is needed, specify the NONE lock type. =item Error: Cannot move away sub-folder $dir =item Warning: Cannot remove folder $name file $filename: $! Writing an empty folder will usually cause that folder to be removed, which fails for the indicated reason. L =item Warning: Cannot remove folder $name file $filename: $! Writing an empty folder will usually cause that folder to be removed, which fails for the indicated reason. L controls whether the empty folder will removed; setting it to false (C<0>) may be needed to avoid this message. =item Error: Cannot replace $filename by $tempname, to update folder $name: $! The replace policy wrote a new folder file to update the existing, but was unable to give the final touch: replacing the old version of the folder file for the indicated reason. =item Warning: Changes not written to read-only folder $self. You have opened the folder read-only --which is the default set by L--, made modifications, and now want to close it. Set L if you want to overrule the access mode, or close the folder with L set to C. =item Error: Copying failed for one message. For some reason, for instance disc full, removed by external process, or read-protection, it is impossible to copy one of the messages. Copying will proceed for the other messages. =item Error: Destination folder $name is not writable. The folder where the messages are copied to is not opened with write access (see L). This has no relation with write permission to the folder which is controlled by your operating system. =item Warning: Different messages with id $msgid The message id is discovered more than once within the same folder, but the content of the message seems to be different. This should not be possible: each message must be unique. =item Error: File too short to get write message $nr ($size, $need) Mail::Box is lazy: it tries to leave messages in the folders until they are used, which saves time and memory usage. When this message appears, something is terribly wrong: some lazy message are needed for updating the folder, but they cannot be retrieved from the original file anymore. In this case, messages can be lost. This message does appear regularly on Windows systems when using the 'replace' write policy. Please help to find the cause, probably something to do with Windows incorrectly handling multiple filehandles open in the same file. =item Warning: Folder $name file $filename is write-protected. The folder is opened writable or for appending via L, but the operating system does not permit writing to the file. The folder will be opened read-only. =item Error: Folder $name not deleted: not writable. The folder must be opened with write access via L, otherwise removing it will be refused. So, you may have write-access according to the operating system, but that will not automatically mean that this C method permits you to. The reverse remark is valid as well. =item Error: Invalid timespan '$timespan' specified. The string does not follow the strict rules of the time span syntax which is permitted as parameter. =item Warning: Message-id '$msgid' does not contain a domain. According to the RFCs, message-ids need to contain a unique random part, then an C<@>, and then a domain name. This is made to avoid the creation of two messages with the same id. The warning emerges when the C<@> is missing from the string. =item Error: Package $package does not implement $method. Fatal error: the specific package (or one of its superclasses) does not implement this method where it should. This message means that some other related classes do implement this method however the class at hand does not. Probably you should investigate this and probably inform the author of the package. =item Error: Unable to create subfolder $name of $folder. The copy includes the subfolders, but for some reason it was not possible to copy one of these. Copying will proceed for all other sub-folders. =item Error: Unable to update folder $self. When a folder is to be written, both replace and inplace write policies are tried, If both fail, the whole update fails. You may see other, related, error messages to indicate the real problem. =back =head1 SEE ALSO This module is part of Mail-Box distribution version 3.009, built on August 18, 2020. Website: F =head1 LICENSE Copyrights 2001-2020 by [Mark Overmeer]. For other contributors see ChangeLog. This program is free software; you can redistribute it and/or modify it under the same terms as Perl itself. See F