diff options
Diffstat (limited to 'fetchmail.man')
| -rw-r--r-- | fetchmail.man | 66 |
1 files changed, 34 insertions, 32 deletions
diff --git a/fetchmail.man b/fetchmail.man index 2300c128..648f7e1b 100644 --- a/fetchmail.man +++ b/fetchmail.man @@ -1070,47 +1070,47 @@ used with the keywords 'esmtpname' and 'esmtppassword'; the former defaults to the username of the calling user. .SH DAEMON MODE -The -.B \-\-daemon <interval> -or -.B \-d <interval> -option runs -.I fetchmail -in daemon mode. You must specify a numeric argument which is a -polling interval in seconds. -.PP +.SS Introducing the daemon mode In daemon mode, .I fetchmail -puts itself in background and runs forever, querying each specified -host and then sleeping for the given polling interval. -.PP -Simply invoking +puts itself into the background and runs forever, querying each +specified host and then sleeping for a given polling interval. +.SS Starting the daemon mode +There are several ways to make fetchmail work in daemon mode. On the +command line, \fB\-\-daemon\ <interval>\fR or \fB\-d\ <interval>\fR +option runs \fIfetchmail\fR in daemon mode. You must specify a numeric +argument which is a polling interval in seconds. +.PP +Example: simply invoking .IP fetchmail \-d 900 .PP will, therefore, poll all the hosts described in your .I ~/.fetchmailrc file (except those explicitly excluded with the 'skip' verb) once -every fifteen minutes. +every 15 minutes. .PP -It is possible to set a polling interval -in your -.I ~/.fetchmailrc -file by saying 'set daemon <interval>', where <interval> is an -integer number of seconds. If you do this, fetchmail will always -start in daemon mode unless you override it with the command-line -option \-\-daemon 0 or \-d0. +It is also possible to set a polling interval +in your \fI~/.fetchmailrc\fR file by saying 'set\ daemon\ <interval>', +where <interval> is an integer number of seconds. If you do this, +fetchmail will always start in daemon mode unless you override it with +the command-line option \-\-daemon 0 or \-d0. .PP Only one daemon process is permitted per user; in daemon mode, -.I fetchmail -makes a per-user lockfile to guarantee this. +\fIfetchmail\fR sets up a per-user lockfile to guarantee this. +(You can however cheat and set the FETCHMAILHOME environment variable to +overcome this setting, but in that case, it is your responsibility to +make sure you aren't polling the same server with two processes at the +same time.) +.SS Awakening the background daemon .PP Normally, calling fetchmail with a daemon in the background sends a -wake-up signal to the daemon, forcing it to poll mailservers -immediately. (The wake-up signal is SIGHUP if fetchmail is running as -root, SIGUSR1 otherwise.) The wake-up action also clears any 'wedged' -flags indicating that connections have wedged due to failed +wake-up signal to the daemon and quits without output. The background +daemon then starts its next poll cycle immediately. The wake-up signal, +SIGUSR1, can also be sent manually. The wake-up action also clears any +'wedged' flags indicating that connections have wedged due to failed authentication or multiple timeouts. +.SS Terminating the background daemon .PP The option .B \-\-quit @@ -1120,6 +1120,7 @@ If the \-\-quit option appears last on the command line, \fIfetchmail\fP will kill the running daemon process and then quit. Otherwise, \fIfetchmail\fP will first kill a running daemon process and then continue running with the other options. +.SS Useful options for daemon mode .PP The .B \-L <filename> @@ -1185,8 +1186,8 @@ file while fetchmail is running in daemon mode, this will be detected at the beginning of the next poll cycle. When a changed .I ~/.fetchmailrc is detected, fetchmail rereads it and restarts from scratch (using -exec(2); no state information is retained in the new instance). Note also -that if you break the +exec(2); no state information is retained in the new instance). +Note also that if you break the .I ~/.fetchmailrc file's syntax, the new instance will softly and silently vanish away on startup. @@ -2497,9 +2498,10 @@ If HOME_ETC and FETCHMAILHOME are set, HOME_ETC will be ignored. .SH SIGNALS If a .I fetchmail -daemon is running as root, SIGHUP wakes it up from its sleep phase and -forces a poll of all non-skipped servers (this is in accordance with -the usual conventions for system daemons). +daemon is running as root, SIGUSR1 wakes it up from its sleep phase and +forces a poll of all non-skipped servers. For compatibility reasons, +SIGHUP can also be used in 6.3.X but may not be available in future +fetchmail versions. .PP If .I fetchmail |