t_info(FP) (TLI/XTI) 6 January 1993 t_info(FP) Name t_info - TLI and XTI transport protocol structure Syntax #include <sys/tiuser> /* TLI only */ #include <xti.h> /* XTI only */ Description The tinfo structure contains the following members: _________________________________________________________________________ Member Description _________________________________________________________________________ long addr; /* max size of the transport protocol address */ long options; /* max number of bytes of protocol-specific options */ long tsdu; /* max size of a transport service data unit (TSDU) */ long etsdu; /* max size of expedited transport service data */ /* unit (ETSDU) */ long connect; /* max data allowed on connection establishment */ long discon; /* max data allowed for tsnddis and trcvdis */ long servtype; /* service type supported by the transport provider */ The values of the members have the following meanings: addr A value greater than or equal to zero indicates the maximum size of a transport protocol address; a value of -1 specifies that there is no limit on the address size; and a value of -2 specifies that the transport provider does not provide user access to transport protocol addresses. options A value greater than or equal to zero indicates the maximum number of bytes of protocol-specific options supported by the provider; a value of -1 specifies that there is no limit on the option size; and a value of -2 specifies that the transport provider does not support user-settable options. tsdu A value greater than zero specifies the maximum size of a transport service data unit (TSDU); a value of zero specifies that the transport provider does not support the concept of TSDU, although it does support the sending of a data stream with no logical boundaries preserved across a connection; a value of -1 specifies that there is no limit on the size of a TSDU; and a value of -2 specifies that the transfer of normal data is not supported by the transport provider. etsdu A value greater than zero specifies the maximum size of an Expedited Transport Service Data Unit (ETSDU); a value of zero specifies that the transport provider does not support the con- cept of ETSDU, although it does support the sending of an expedited data stream with no logical boundaries preserved across a connection; a value of -1 specifies that there is no limit on the size of an ETSDU; and a value of -2 specifies that the transfer of expedited data is not supported by the trans- port provider. connect A value greater than or equal to zero specifies the maximum amount of data that can be associated with connection estab- lishment functions; a value of -1 specifies that there is no limit on the amount of data sent during connection establish- ment; and a value of -2 specifies that the transport provider does not allow data to be sent with connection establishment functions. discon A value greater than or equal to zero specifies the maximum amount of data that can be associated with the tsnddis(S) and trcvdis(S) functions; a value of -1 specifies that there is no limit on the amount of data sent with these abortive release functions; and a value of -2 specifies that the transport pro- vider does not allow data to be sent with the abortive release functions. servtype This member specifies the service type supported by the trans- port provider, as described below. If a transport user is concerned with protocol independence, the above sizes can be accessed to determine how large the buffers must be to hold each piece of information. Alternatively, the talloc(S) function can be used to allocate these buffers. An error results if a transport user exceeds the allowed data size on any function. The value of each member can change as a result of option negotiation, and tgetinfo(S) enables a user to retrieve the current characteristics. The servtype member of tinfo structure may specify one of the following values on return: TCOTS The transport provider supports a connection-mode service but does not support the optional orderly release facility. TCOTSORD The transport provider supports a connection-mode service with the optional orderly release facility. TCLTS The transport provider supports a connectionless-mode ser- vice. For this service type, topen(S) returns -2 for etsdu, connect, and discon.