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Maildir
The Maildir e-mail format is a common way of storing email messages in which each message is stored in a separate file with a unique name, and each mail folder is a file system directory. The local file system handles file locking as messages are added, moved and deleted. A major design goal of Maildir is to eliminate the need for program code to handle file locking and unlocking. __TOC__ Specifications A Maildir directory (often named Maildir) usually has three subdirectories named tmp, new, and cur. The tmp subdirectory temporarily stores e-mail messages that are in the process of being delivered. This subdirectory may also store other kinds of temporary files. The new subdirectory stores messages that have been delivered, but have not yet been seen by any mail application. The cur subdirectory stores messages that have already been seen by mail applications. Maildir++ Sam Varshavchik, the author of the Courier Mail Server and other software, wrote an extension to th ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Maildir
The Maildir e-mail format is a common way of storing email messages in which each message is stored in a separate file with a unique name, and each mail folder is a file system directory. The local file system handles file locking as messages are added, moved and deleted. A major design goal of Maildir is to eliminate the need for program code to handle file locking and unlocking. __TOC__ Specifications A Maildir directory (often named Maildir) usually has three subdirectories named tmp, new, and cur. The tmp subdirectory temporarily stores e-mail messages that are in the process of being delivered. This subdirectory may also store other kinds of temporary files. The new subdirectory stores messages that have been delivered, but have not yet been seen by any mail application. The cur subdirectory stores messages that have already been seen by mail applications. Maildir++ Sam Varshavchik, the author of the Courier Mail Server and other software, wrote an extension to th ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Qmail
qmail is a mail transfer agent (MTA) that runs on Unix. It was written, starting December 1995, by Daniel J. Bernstein as a more secure replacement for the popular Sendmail program. Originally license-free software, qmail's source code was later dedicated in the public domain by the author. Features Security When first published, qmail was the first security-aware mail transport agent; since then, other security-aware MTAs have been published. The most popular predecessor to qmail, Sendmail, was not designed with security as a goal, and as a result has been a perennial target for attackers. In contrast to sendmail, qmail has a modular architecture composed of mutually untrusting components; for instance, the SMTP listener component of qmail runs with different credentials from the queue manager or the SMTP sender. qmail was also implemented with a security-aware replacement to the C standard library, and as a result has not been vulnerable to stack and heap overf ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
E-mail
Electronic mail (email or e-mail) is a method of exchanging messages ("mail") between people using electronic devices. Email was thus conceived as the electronic (digital) version of, or counterpart to, mail, at a time when "mail" meant only physical mail (hence '' e- + mail''). Email later became a ubiquitous (very widely used) communication medium, to the point that in current use, an email address is often treated as a basic and necessary part of many processes in business, commerce, government, education, entertainment, and other spheres of daily life in most countries. ''Email'' is the medium, and each message sent therewith is also called an ''email.'' The term is a mass noun. Email operates across computer networks, primarily the Internet, and also local area networks. Today's email systems are based on a store-and-forward model. Email servers accept, forward, deliver, and store messages. Neither the users nor their computers are required to be online simulta ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Dovecot (software)
Dovecot is an open-source IMAP and POP3 server for Unix-like operating systems, written primarily with security in mind. Timo Sirainen originated Dovecot and first released it in July 2002. Dovecot developers primarily aim to produce a lightweight, fast and easy-to-set-up open-source email server. The primary purpose of Dovecot is to act as mail storage server. Mail is delivered to the server using some mail delivery agent (MDA) and stored for later access with an email client (mail user agent, or MUA). Dovecot can also act as mail proxy server, forwarding connection to another mail server, or act as a lightweight MUA in order to retrieve and manipulate mail on remote server for e.g. mail migration. According to thOpen Email Survey as of 2020, Dovecot has an installed base of at least 2.9million IMAP servers, and has a global market share of 76.9% of all IMAP servers. The results of the same survey in 2019 gave figures of 2.6million and 76.2%, respectively. Features Dovecot ca ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Internet Message Access Protocol
In computing, the Internet Message Access Protocol (IMAP) is an Internet standard protocol used by email clients to retrieve email messages from a mail server over a TCP/IP connection. IMAP is defined by . IMAP was designed with the goal of permitting complete management of an email box by multiple email clients, therefore clients generally leave messages on the server until the user explicitly deletes them. An IMAP server typically listens on port number 143. IMAP over SSL/TLS (IMAPS) is assigned the port number 993. Virtually all modern e-mail clients and servers support IMAP, which along with the earlier POP3 (Post Office Protocol) are the two most prevalent standard protocols for email retrieval. Many webmail service providers such as Gmail and Outlook.com also provide support for both IMAP and POP3. Email protocols The Internet Message Access Protocol is an application layer Internet protocol that allows an e-mail client to access email on a remote mail server. The curr ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Email
Electronic mail (email or e-mail) is a method of exchanging messages ("mail") between people using electronic devices. Email was thus conceived as the electronic ( digital) version of, or counterpart to, mail, at a time when "mail" meant only physical mail (hence '' e- + mail''). Email later became a ubiquitous (very widely used) communication medium, to the point that in current use, an email address is often treated as a basic and necessary part of many processes in business, commerce, government, education, entertainment, and other spheres of daily life in most countries. ''Email'' is the medium, and each message sent therewith is also called an ''email.'' The term is a mass noun. Email operates across computer networks, primarily the Internet, and also local area networks. Today's email systems are based on a store-and-forward model. Email servers accept, forward, deliver, and store messages. Neither the users nor their computers are required to be online simu ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Post Office Protocol
In computing, the Post Office Protocol (POP) is an application-layer Internet standard protocol used by e-mail clients to retrieve e-mail from a mail server. POP version 3 (POP3) is the version in common use, and along with IMAP the most common protocols for email retrieval. Purpose The Post Office Protocol provides access via an Internet Protocol (IP) network for a user client application to a mailbox (''maildrop'') maintained on a mail server. The protocol supports download and delete operations for messages. POP3 clients connect, retrieve all messages, store them on the client computer, and finally delete them from the server. This design of POP and its procedures was driven by the need of users having only temporary Internet connections, such as dial-up access, allowing these users to retrieve e-mail when connected, and subsequently to view and manipulate the retrieved messages when offline. POP3 clients also have an option to leave mail on the server after download. By con ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Biff (Unix)
is a mail notification system for Unix. Usage When a new mail message is delivered, the program alerts the recipient so they can read it immediately. The alert is sent to the tty where the recipient is logged in, and contains the ''Subject'', ''From'' line, and first few lines of the body of the new message. The alert also includes terminal beeps to guarantee quick attention. Notification is enabled by the command : and disabled by : Comsat The biff utility was the user interface used to change notification preferences. The actual act of notifying the user was performed by a daemon called (short for "communications satellite A communications satellite is an artificial satellite that relays and amplifies radio telecommunication signals via a transponder; it creates a communication channel between a source transmitter and a receiver at different locations on Earth ..."). The daemon received messages via UDP describing the update to the mailbox, and would then info ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Timo Sirainen
Timo Sirainen, born 1979, is a Finnish programmer also known under the nickname, handles "cras" and "tss". Sirainen is the original author of the IRC-client Irssi and the POP3, POP/IMAP server Dovecot (software), Dovecot. Sirainen lives in Helsinki, Finland. In 2006, Sirainen began studying biotechnology at the University of Tampere. He was formerly working for Rackspace Email & Apps (formerly Mailtrust), where he continued the development of the Dovecot (software), Dovecot POP/IMAP server. Since May 2011 he runs his own company offering commercial support for Dovecot. In March 2015, the companies Dovecot Oy and Open-Xchange SA announced a merger. References [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Hard Link
In computing, a hard link is a directory entry (in a directory-based file system) that associates a name with a file. Thus, each file must have at least one hard link. Creating additional hard links for a file makes the contents of that file accessible via additional paths (i.e., via different names or in different directories). This causes an alias effect: a process can open the file by any one of its paths and change its content. By contrast, a soft link or “shortcut” to a file is not a direct link to the data itself, but rather a reference to a hard link or another soft link. Every directory is itself a special file, only it contains a list of file names. Hence, multiple hard links to directories are possible, which could create a circular directory structure, rather than a branching structure like a tree. For that reason, some file systems forbid the creation of hard links to directories. POSIX-compliant operating systems, such as Linux, Android, macOS, and the W ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Rsync
rsync is a utility for efficiently transferring and synchronizing files between a computer and a storage drive and across networked computers by comparing the modification times and sizes of files. It is commonly found on Unix-like operating systems and is under the GPL-3.0-or-later license. Rsync is written in C as a single threaded application. The rsync algorithm is a type of delta encoding, and is used for minimizing network usage. Zlib may be used for additional data compression, and SSH or stunnel can be used for security. Rsync is typically used for synchronizing files and directories between two different systems. For example, if the command rsync local-file user@remote-host:remote-file is run, rsync will use SSH to connect as user to remote-host. Once connected, it will invoke the remote host's rsync and then the two programs will determine what parts of the local file need to be transferred so that the remote file matches the local one. One application of ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Rename (computing)
In computing, rename refers to the altering of a name of a file. This can be done manually by using a shell command such as ren or mv, or by using batch renaming software that can automate the renaming process. Implementations The C standard library provides a function called ''rename'' which does this action. In POSIX, which is extended from the C standard, the ''rename'' function will fail if the old and new names are on different mounted file systems. In SQL, renames are performed by using the CHANGE specification in ALTER TABLE statements. Atomic rename In POSIX, a successful call to ''rename'' is guaranteed to have been atomic from the point of view of the current host (i.e., another program would only see the file with the old name or the file with the new name, not both or neither of them). This aspect is often used during a file save operation to avoid any possibility of the file contents being lost if the save operation is interrupted. The ''rename'' function from th ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
