Herafter a short extract of the SigdB interface:

Function Name	Purpose
sig_New	Initializes a new Signaling handle. The user-application specifies for which purpose the signaling handle has been created: signaling in MPLS networks, or in GMPLS networks (either generic, or OUNI - Client or network side, or E-NNI interfaces) and if fault handling must be automatically handled.
sig_MSG_new	Creates a new Signaling Message object.
sig_MSG_setCall	Provides the Call object that must be specified by this signaling message. Such an object is mandatory for call-related signaling messages. It may also be used with connection-related signaling messages, in case of simultaneous call and connection establishment, or when a new connection is added to an existing call.
sig_MSG_setExcludeRoute	Provides a sequence of Hop object handles. This list is the Exclude Route (if any) that must be specified by the signaling message.
sig_MSG_setKey	Specifies the Key object identifying the LSP targeted by this signaling message. This function must not be called if the signaling message does not target a particular LSP (e.g., some notifications).
sig_MSG_setLabel	Provides a handle to the Label object (if any) that must be specified by the signaling message. This is the label assigned to the forward LSP by the downstream LSR, or the upstream label assigned to the reverse LSP by the upstream LSR (bi-directional LSP).
sig_MSG_send	This function sends a signaling message to a peer LSR, and updates the Signaling database based on the information carried by this message.
sig_Listen	This function listens for signaling messages received from the communication stack. The caller provides a callback function, which is called each time such a message is received.