The name of a registered signal.

Input Format:

A case-insensitive word starting with a letter. After the first character, letters, numeric digits and underscore characters are allowed.

Predefined signals:

source_set - This signal is sent whenever a source sets, or one sends a command (such as an offset) that results in the source being unreachable below the telescope elevation limit. The signal is cleared whenever a telescope positioning control command is executed. The signal is resent at this point if the modified target position is still below the elevation limit.

Example:

The following example sends a "quit" signal to a running schedule.

 signal quit

Context:

The add_signals command defines a set of signal names that can be used by the signalling facility. These names are the only ones that are allowed as the values of subsequent Signal variables and arguments.