TrySystem( )
Tries to execute an operating system command
TrySystem(command)
Attempts to execute a command in the underlying operating system. If the command itself executes but is in error, and if there exists a priority n+101 (where n is the current priority), the execution of the dialplan will continue at that priority level.
This application is very similar to the System( ) application, except that it always returns 0, whereas the System( ) application will return -1 if it is unable to execute the system command.
exten => 123,1,TrySystem(echo hello > /tmp/hello.txt)