If you cloned the git repo, you first need to build the documentation.
On a Debian based system:
```
-$ sudo apt install -y docbook docbook-xsl docbook-xml docbook-utils manpages-dev
+$ sudo apt install -y autoconf build-essential docbook docbook-xsl docbook-xml docbook-utils manpages-dev
$ autoconf
$ ./configure # optionally, use: --without-sendmail
$ make updatedoc
<term><option>--maxserial</option>
<replaceable>num</replaceable></term>
<listitem>
- <para>Set to <replaceable>num</replaceable> the maximum number
- of serial jobs which can run simultaneously. By default,
- this value is set to &serialmaxrunning;.</para>
+ <para>Run at most <replaceable>num</replaceable> serial jobs
+ simultaneously. By default, this value is set to &serialmaxrunning;.</para>
<para>&seealso; option &optserial; in &fcrontab;(5).</para>
</listitem>
</varlistentry>
<term><option>-q</option> <replaceable>num</replaceable></term>
<term><option>--queuelen</option> <replaceable>num</replaceable></term>
<listitem>
- <para>Set to n the number of jobs the serial queue and
-the lavg queue can contain.</para>
+ <para>Sets the sizes of the queues that are used to manage serial
+ jobs and the lavg queue each to <replaceable>num</replaceable>.
+ This means that
+ (A) at most <replaceable>num</replaceable> serial jobs can be
+ in the waiting state and
+ (B) at most <replaceable>num</replaceable> jobs can wait until the
+ system average load drops below a certain value.
+ </para>
</listitem>
</varlistentry>
<varlistentry>
<filename>&etc;/&fcron.conf.location;</filename>. To interact with that running
&fcron; process, &fcrontab; must use the same config file (which is defined by
&fcrontab;'s option <option>-c</option>). That way, several &fcron; processes
-can run simultaneously on an only system (but each &fcron; process *must* have a
+can run simultaneously on a single system (but each &fcron; process *must* have a
different spool dir and pid file from the other processes).</para>
</listitem>
</varlistentry>
</para>
</abstract>
<para>
- Blank lines, line beginning by a hash sign (#) (which are
- considered comments), leading blanks and tabs are ignored. Each line in a
+ Blank lines, lines beginning with a hash sign (#) (which are
+ considered as comments), leading blanks and tabs are ignored. Each line in a
&fcron.conf; file is of the form
<blockquote>
<para>name = value</para>
<replaceable>file</replaceable> instead of default config file
<filename>&etc;/&fcron.conf.location;</filename>. To interact with a running
&fcron; process, &fcrondyn; must use the same config file as the process. That
-way, several &fcron; processes can run simultaneously on an only system.</para>
+way, several &fcron; processes can run simultaneously on a single system.</para>
</listitem>
</varlistentry>
<varlistentry>
</refmeta>
<refnamediv>
<refname>fcrontab</refname> <refpurpose>manipulate per-user fcrontab
- files</refpurpose>
+ files which adhere to the format defined in <link linkend="fcrontab.5">&fcrontab;(5)</link></refpurpose>
</refnamediv>
<refsynopsisdiv id="fcrontab.1.synopsis">
linkend="fcron.8">&fcron;(8)</link> daemon. As &fcron; internally
uses a non-human readable format (this is needed because &fcron;
saves more informations than the user gives, for example the time
- and date of next execution), the user cannot edit directly his
-
&fcrontabf; (the one used by &fcron;).</para> <para>When a user
+ and date of next execution), the user cannot edit their &fcrontabf;
+
directly (the one used by &fcron;).</para> <para>When a user
installs a &fcrontabf;, the source file is saved in the spool
- directory (<filename>&fcrontabsdir;</filename>) to allow future
- editions, and a formatted file is generated for the &fcron; daemon,
- which is signaled once about ten seconds before the next minute for
- all changes made previously. The daemon is not informed of the changes
- immediately but at most once a minute
+ directory (<filename>&fcrontabsdir;</filename>) to allow it to be
+ edited, and a formatted file is generated for the &fcron; daemon.
+ This formatted (non human readable) file with all recent changes
+ included is then sent to the daemon.
+ The daemon is not informed of the changes immediately but after some time
to keep ill disposed users from blocking the daemon by installing
- &fcrontabf;s over and over (ie. denial of service attack). We will call
+ &fcrontabf;s over and over (i.e. denial of service attack).
+ By default, the file is sent once per minute (about ten seconds before
+ the full minute) to the daemon, the build time parameter
+ <option>--with-max-fcrontab-reload-delay-seconds</option>
+ can be used to specify a different maximum time to send this data.
+ We will call
"<emphasis>fcrontab</emphasis>" the source file of the &fcrontabf;
- in the following.</para> <para>A user can install a &fcrontabf; if
- he is listed in the <filename>&etc;/&fcron.allow;</filename> and not
- (unless by the keyword all) listed in
+ in the following.</para>
+ <para>The fcrontab files that a user modifies has to follow the format
+ defined in <link linkend="fcrontab.5">&fcrontab;(5)</link> .</para>
+ <para>Users can install a &fcrontabf; if
+ they are listed in <filename>&etc;/&fcron.allow;</filename> and not listed in
<filename>&etc;/&fcron.deny;</filename> (see section "<link
- linkend="fcrontab.1.files">files</link>" below). If neither
+ linkend="fcrontab.1.files">files</link>" below).
+ The keyword 'all' is a shorthand for all users. If neither
<filename>fcron.allow</filename> nor <filename>fcron.deny</filename>
exist, all users are allowed. None of these files have to exist, but
if they do, the deny file takes precedence.</para> <para>The first
form of the command is used to install a new &fcrontabf; file, from
- any named file or from standard input if the pseudo-filename "-" is
- given, replacing the previous one (if any): each user can have only
+ any named file or from standard input (if the pseudo-filename "-" is
+ given), replacing the previous one (if any). Each user can have only
one &fcrontabf;.</para> <para>For instance, root can create a
systemwide fcrontab file, say <filename>/etc/fcrontab</filename>,
and run "<command>fcrontab</command>
<filename>/etc/fcrontab</filename>" to install the new version after
- each change of the file. Or (s)he can create a new fcrontab running
+ each change of the file. Or root can create a new fcrontab running
a simple "<command>fcrontab</command>", and then maintain it using
"<command>fcrontab</command> <option>-e</option>". Same
considerations apply to a non privileged user.</para>
file <filename>&etc;/&fcron.conf.location;</filename>. To
interact with a running &fcron; process, &fcrontab; must
use the same config file as the process. That way, several
- &fcron; processes can run simultaneously on an only
+ &fcron; processes can run simultaneously on a single
system.</para>
</listitem>
</varlistentry>
</refmeta>
<refnamediv>
<refname>fcrontab</refname>
- <refpurpose>tables for driving fcron</refpurpose>
+ <refpurpose>file format to define the jobs that fcron should run, and their schedules.</refpurpose>
</refnamediv>
<refsect1>
<para>A &fcrontabf; is a file containing all tables used by the
&fcron;(8) daemon. In other words, it is the means for a user to tell the daemon
"execute this command at this moment". Each user has their own &fcrontabf;, whose
-commands are executed as their owner (only root can run a job as another using the
+commands are executed on behalf of their owner (in particular with the users
+permissions -- only root can run a job as another using the
option &optrunas; (see below)).</para>
<para>Blank lines, line beginning by a hash sign (#) (which are
considered comments), leading blanks and tabs are ignored. Each line in a
<term>b</term>
<listitem>
<para><emphasis><type>boolean</type></emphasis>(<constant>false</constant>)</para>
- <para>Run an &-line at &fcron;'s startup (or system's resume after suspend/hibernation) if it should
+ <para>Run an &-line (i.e. based on date and time) at &fcron;'s startup (or system's resume after suspend/hibernation) if it should
have run during system down time.</para>
</listitem>
</varlistentry>
Cron</application>, so it implements most of its functionalities.</para>
<para>But contrary to <application>Vixie Cron</application>, &fcron;
does not need your system to be up 7 days a week, 24 hours a day: it also works
-well with systems which are not running neither all the time nor regularly
+well with systems which are neither running all the time nor regularly
(contrary to <application>anacrontab</application>).</para>
<para>In other words, &fcron; does both the job of <application>Vixie
Cron</application> and <application>anacron</application>, but does even more
and better :)) ...</para>
<para>To do so, &fcron; allows you to use the standard mode in which you
-tell it to execute one command at a given date and hour and to make it run a
-command according to its time of execution, which is normally the same as system
-up time. For example:
+tell it to execute one command at a given date and time. Alternatively you can
+instruct &fcron; to execute a command after a certain duration of &fcron;'s runtime
+(which is normally the same as system up time because &fcron; is typically started
+on boot). For example:
<blockquote>
<para>Run the task 'save /home/ directory' every 3h15 of system
</blockquote> and, of course, in order to make it really useful, the
time remaining until next execution is saved each time the system is stopped.
You can also say:
-
+
<blockquote>
<para>run that command once between 2am and 5am</para>
</blockquote> which will be done if the system is running at any
projects / thirdparty / fcron.git / commitdiff
