SYNOPSIS

In rpc/rpc.h Ft bool_t Fn svc_control SVCXPRT *svc const u_int req void *info Ft int Fn svc_create void (*dispatch)(struct svc_req *, SVCXPRT *) const rpcprog_t prognum const rpcvers_t versnum const char *nettype Ft SVCXPRT * Fn svc_dg_create const int fildes const u_int sendsz const u_int recvsz Ft void Fn svc_destroy SVCXPRT *xprt Ft SVCXPRT * Fn svc_fd_create const int fildes const u_int sendsz const u_int recvsz Ft SVCXPRT * Fn svc_raw_create void Ft SVCXPRT * Fn svc_tli_create const int fildes const struct netconfig *netconf const struct t_bind *bindaddr const u_int sendsz const u_int recvsz Ft SVCXPRT * Fn svc_tp_create void (*dispatch)(struct svc_req *, SVCXPRT *) const rpcprog_t prognum const rpcvers_t versnum const struct netconfig *netconf Ft SVCXPRT * Fn svc_vc_create const int fildes const u_int sendsz const u_int recvsz

DESCRIPTION

These routines are part of the RPC library which allows C language programs to make procedure calls on servers across the network. These routines deal with the creation of service handles. Once the handle is created, the server can be invoked by calling Fn svc_run .

Routines

See rpc(3) for the definition of the Vt SVCXPRT data structure.

Fn svc_control

A function to change or retrieve various information about a service object. The Fa req argument indicates the type of operation and Fa info is a pointer to the information. The supported values of Fa req , their argument types, and what they do are:

SVCGET_VERSQUIET

If a request is received for a program number served by this server but the version number is outside the range registered with the server, an RPC_PROGVERSMISMATCH error will normally be returned. The Fa info argument should be a pointer to an integer. Upon successful completion of the SVCGET_VERSQUIET request, Fa *info contains an integer which describes the server's current behavior: 0 indicates normal server behavior (that is, an RPC_PROGVERSMISMATCH error will be returned); 1 indicates that the out of range request will be silently ignored.

SVCSET_VERSQUIET

If a request is received for a program number served by this server but the version number is outside the range registered with the server, an RPC_PROGVERSMISMATCH error will normally be returned. It is sometimes desirable to change this behavior. The Fa info argument should be a pointer to an integer which is either 0 (indicating normal server behavior - an RPC_PROGVERSMISMATCH error will be returned), or 1 (indicating that the out of range request should be silently ignored).

Fn svc_create

The Fn svc_create function creates server handles for all the transports belonging to the class Fa nettype . The Fa nettype argument defines a class of transports which can be used for a particular application. The transports are tried in left to right order in NETPATH variable or in top to bottom order in the netconfig database. If Fa nettype is NULL it defaults to Qq netpath .

The Fn svc_create function registers itself with the rpcbind service (see rpcbind(8)). The Fa dispatch function is called when there is a remote procedure call for the given Fa prognum and Fa versnum ; this requires calling Fn svc_run (see Fn svc_run in rpc_svc_reg3). If Fn svc_create succeeds, it returns the number of server handles it created, otherwise it returns 0 and an error message is logged.

Fn svc_destroy

A function macro that destroys the RPC service handle Fa xprt . Destruction usually involves deallocation of private data structures, including Fa xprt itself. Use of Fa xprt is undefined after calling this routine.

Fn svc_dg_create

This routine creates a connectionless RPC service handle, and returns a pointer to it. This routine returns NULL if it fails, and an error message is logged. The Fa sendsz and Fa recvsz arguments are arguments used to specify the size of the buffers. If they are 0, suitable defaults are chosen. The file descriptor Fa fildes should be open and bound. The server is not registered with rpcbind(8).

Warning: since connectionless-based RPC messages can only hold limited amount of encoded data, this transport cannot be used for procedures that take large arguments or return huge results.

Fn svc_fd_create

This routine creates a service on top of an open and bound file descriptor, and returns the handle to it. Typically, this descriptor is a connected file descriptor for a connection-oriented transport. The Fa sendsz and Fa recvsz arguments indicate sizes for the send and receive buffers. If they are 0, reasonable defaults are chosen. This routine returns NULL if it fails, and an error message is logged.

Fn svc_raw_create

This routine creates an RPC service handle and returns a pointer to it. The transport is really a buffer within the process's address space, so the corresponding RPC client should live in the same address space; (see Fn clnt_raw_create in rpc_clnt_create3). This routine allows simulation of RPC and acquisition of RPC overheads (such as round trip times), without any kernel and networking interference. This routine returns NULL if it fails, and an error message is logged.

Note: Fn svc_run should not be called when the raw interface is being used.

Fn svc_tli_create

This routine creates an RPC server handle, and returns a pointer to it. The Fa fildes argument is the file descriptor on which the service is listening. If Fa fildes is RPC_ANYFD it opens a file descriptor on the transport specified by Fa netconf . If the file descriptor is unbound and Fa bindaddr is not NULL Fa fildes is bound to the address specified by Fa bindaddr , otherwise Fa fildes is bound to a default address chosen by the transport.

Note: the Vt t_bind structure comes from the TLI/XTI SysV interface, which Nx does not use. The structure is defined in In rpc/types.h for compatibility as:

struct t_bind {
    struct netbuf addr; /* network address, see rpc(3) */
    unsigned int  qlen; /* queue length (for listen(2)) */
};

In the case where the default address is chosen, the number of outstanding connect requests is set to 8 for connection-oriented transports. The user may specify the size of the send and receive buffers with the arguments Fa sendsz and Fa recvsz ; values of 0 choose suitable defaults. This routine returns NULL if it fails, and an error message is logged. The server is not registered with the rpcbind(8) service.

Fn svc_tp_create

The Fn svc_tp_create function creates a server handle for the network specified by Fa netconf , and registers itself with the rpcbind service. The Fa dispatch function is called when there is a remote procedure call for the given Fa prognum and Fa versnum ; this requires calling Fn svc_run . The Fn svc_tp_create function returns the service handle if it succeeds, otherwise a NULL is returned and an error message is logged.

Fn svc_vc_create

This routine creates a connection-oriented RPC service and returns a pointer to it. This routine returns NULL if it fails, and an error message is logged. The users may specify the size of the send and receive buffers with the arguments Fa sendsz and Fa recvsz ; values of 0 choose suitable defaults. The file descriptor Fa fildes should be open and bound. The server is not registered with the rpcbind(8) service.

AVAILABILITY

These functions are part of libtirpc.