Using The include, tryinclude and exec Constructs
include, tryinclude and exec¶
Note
You might have arrived here looking for Include Statements specific to Asterisk dialplan.
There are two other constructs we can use within all of our configuration files. They are #include and #exec.
The #include construct tells Asterisk to read in the contents of another configuration file, and act as though the contents were at this location in this configuration file. The syntax is #include filename, where filename is the name of the file you'd like to include. This construct is most often used to break a large configuration file into smaller pieces, so that it's more manageable. The asterisk/star character will be parsed in the path, allowing for the inclusion of an entire directory of files. If the target file specified does not exist, then Asterisk will not load the module that contains configuration with the #include directive.
The #tryinclude construct is the same as #include except it won't stop Asterisk from loading the module when the target file does not exist.
The #exec takes this one step further. It allows you to execute an external program, and place the output of that program into the current configuration file. The syntax is #exec program, where program is the name of the program you'd like to execute.
The #exec, #include, and #tryinclude constructs do not work in the following configuration files:
- asterisk.conf
- modules.conf
Enabling #exec Functionality
The #exec construct is not enabled by default, as it has some risks both in terms of performance and security. To enable this functionality, go to the asterisk.conf configuration file (by default located in /etc/asterisk) and set execincludes=yes in the [options] section. By default both the [options] section heading and the execincludes=yes option have been commented out, you you'll need to remove the semicolon from the beginning of both lines.
Examples¶
Let's look at example of both constructs in action. This is a generic example meant to illustrate the syntax usage inside a configuration file.
You can use #tryinclude if there is any chance the target file may not exist and you still want Asterisk to load the configuration for the module.
Here is a more realistic example of how #exec might be used with real-world commands.