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Semaphore Files

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MDaemon is equipped with support for Semaphore Files, which can be used for a variety of purposes, including causing MDaemon to perform specific actions. Periodically MDaemon will scan the \APP\ subfolder for the existence of these files. If it finds one, the associated behavior is triggered and the semaphore file is removed. This provides for a simple mechanism that enables administrators and developers to manipulate MDaemon without actually handling the interface. The following is a list of the semaphores and what they do:




This semaphore creates new accounts.  It is used to force MDaemon to append new records to the end of the USERLIST.DAT file without causing a potentially time consuming complete rebuild of the user database. Each line in this file must be a complete account record of the form specified in the Account Management Functions section of the MDaemon API (see MD-API.html in MDaemon's \docs\API\ subfolder). Multiple new accounts can be specified – one account record per line.  MDaemon will process the file one line at a time and add each new account.  You can create ADDUSER.LCK to lock the file while you are updating it and MDaemon will not touch ADDUSER.SEM until ADDUSER.LCK is deleted. To see a sample ADDUSER.SEM file open ADDUSER.SMP in your APP directory with a text editor.


Displays in a pop-up window the contents of the semaphore file to all WorldClient users who are logged in when the file is created. It is not, however, displayed to all users immediately—it is displayed to each user individually the next time his or her browser makes a request to the WorldClient server.

Note: Unlike other semaphore files, this file is WorldClient specific. Instead of placing it in the \app\ directory it must be placed in the \MDaemon\WorldClient\ directory.


Reloads aliases data file(s).


Reloads the Auto Responder exception file(s).


Reloads Backscatter Protection (BATV) data file(s).


This SEM manually starts the Bayesian learning process. This is like clicking the Learn button on the Bayesian tab of the Spam Filter. Note: this will start the Bayesian learning procedure even if you have Bayesian learning disabled.


Reloads blacklist data file(s)


Reloads the internal cache of Catalog names.


Reloads Content Filter rules, clears Content Filter cached data, reloads the Spam Filter's White List (no filtering) file.


The results of user quota checks are maintained in the quotacounts.dat file. If you wish to clear the cached quota value for a user, add the user’s email address to this SEM file and then place it in the \app\ folder. If an asterisk ( * ) is on a line by itself, the entire file will be deleted thereby invalidating all cached quota counts.


You can use this semaphore file to delete one or more user accounts. Create a text file containing the addresses of each account that you want to be deleted (one address per line), name the file DELUSER.SEM and then move it to MDaemon's \app\ directory. MDaemon will delete the accounts and then delete the DELUSER.SEM file.


Reloads domain sharing data file.


This semaphore is used to update specific records within the USERLIST.DAT file without a potentially time consuming complete rebuild.  To update a specific record within USERLIST.DAT you first construct a complete replacement record according to the format specified in the Account Management Functions section of the MDaemon API (see MD-API.html in MDaemon's \docs\API\ subfolder). The new record will reflect the changes that need to be updated within USERLIST.DAT.  How does MDaemon know which record in USERLIST.DAT to update? This is accomplished by prepending the new record with the original record's email address followed by a comma. The EDITUSER.SEM file can contain multiple records to update – each on its own line. MDaemon will process the file one line at a time. You can create EDITUSER.LCK to lock the file while you are updating it and MDaemon will not touch EDITUSER.SEM until EDITUSER.LCK is deleted.  To see a sample EDITUSER.SEM file open EDITUSER.SMP in your \APP\ directory with a text editor.


Forces MDaemon to reload the EXCPTION.DAT file.


Shuts down MDaemon.


For optimal performance, MDaemon keeps its list of gateways in memory. Create a GATEWAYS.SEM in MDaemon's APP directory for it to reload the gateways.dat file.


Reloads Greylisting data file(s).


Reloads account grouping data file(s).


Reloads the internal cache of Mailing List names.


Forces a conditional hang-up of RAS device.  MDaemon will wait for any pending mail sessions to close and will then hang-up the RAS session.


Forces unconditional hang-up of RAS device. This is an immediate and unconditional hang-up without regard to mail sessions which may be in progress across the connection.


Reloads Host Screen data file(s).


Reloads IP Screen data file(s).


Reloads LDAP and gateway user data file(s).


Prevents all semaphore file processing until user removes it.


Reloads log file settings.


Reloads the Spam Filter white list and MDSPAMD, which forces it to reinitialize all its configuration data.


Reloads MX Cache data file(s).


Reloads DNSBL white list file.


MDaemon will create this semaphore file once it makes a successful connection using RAS to the ISP.  MD will remove the semaphore once the connection has been terminated.  This is useful if you want to know when MD is using the RAS sub-system.


MDaemon will create this file immediately after a connection made by MDaemon is taken down.


MDaemon will create this file just before trying to use RAS/DUN.  This will allow other software to detect when it should free the dialup port so that MDaemon can use it.


Reloads Priority mail data file(s).


Initiates delivery of Bad Queue content.


Initiates construction and delivery of mailing list digests.


Initiates delivery of Holding Queue content.


Initiates a check for remote mail and delivery of queued remote mail. Note: If you send a message to "" MDaemon will generate the PROCNOW.SEM file. As a result of this, you can't use "procnow" as an email mailbox for one of your accounts.


MDaemon will immediately go into mail processing mode and transact all remote mail.


Initiates delivery of Retry Queue content.


Reloads auto-pruning settings.


Just before a mail session begins MDaemon will create this semaphore file. Inside the file will be a datestamp indicating the time and date of the most recent mail processing interval.


Stops and then starts MDaemon.


Stops and restarts CFEngine.exe (the Content Filter executable).


Reloads all cached data settings and files except for Content Filter settings and files.


Reloads reverse lookups exception file.


Reloads schedule data file(s).


Reloads spam honeypots data files(s)


Reloads SPF, DK, DKIM, and VBR data files(s).


Reloads black list settings and clears cached domain settings.


Reloads tarpit and dynamic screening data file(s).


Reloads the header translation data files.


Redraws MDaemon's icon in the system tray.


Trusted domains and IP addresses are kept memory resident for optimal performance. If you need to reload these settings manually you can create TRUST.SEM to do it.


Initiates SecurityPlus for MDaemon antivirus definition update.


Initiates a Spam Filter update.


Reload the USERLIST.DAT file. Use this when you make modifications to the USERLIST.DAT and need MDaemon to reload it.


MDaemon will check for and remove this semaphore from the APP directory at approximately 10-20 second intervals.  This file can be used by external apps to check if MDaemon is running.  If this file remains in the APP directory for more than 20 seconds, that is a good indication that MDaemon is no longer running.