clnt_create - Linux

Overview

The clnt_create command is a core function within Sun’s RPC (Remote Procedure Call) library, used for creating a client handle for remote procedure calls. It establishes a connection with a server and allows the client to make remote procedure calls to that server.

Syntax

clnt_create(const char* host, u_long prog, u_long vers, const char* proto)

Options/Flags

  • host: Specifies the hostname or IP address of the server to connect to.
  • prog: The program number of the RPC service on the server.
  • vers: The version number of the RPC service on the server.
  • proto: The protocol to use for the RPC connection. Valid options include "tcp" and "udp".

Examples

Simple Example: Create a client handle to the rpcbind service on the remote host example.com:

clnt_create("example.com", RPCBINDPROGRAM, RPCBINDVERSION, "tcp");

Advanced Example: Create a client handle to the nfs service on the remote host 192.168.1.100 using UDP:

clnt_create("192.168.1.100", NFS_PROGRAM, NFS_VERSION, "udp");

Common Issues

  • Connection refused: Ensure that the RPC service is running on the server and that the hostname or IP address is correct.
  • RPC protocol not supported: Verify that the protocol specified in the proto argument is supported by the server.
  • RPC program or version not found: Confirm that the program number and version number provided are valid for the RPC service on the server.

Integration

The client handle created by clnt_create can be used with other RPC library functions, such as clnt_call and clnt_destroy, to make remote procedure calls and manage the RPC connection.

Related Commands

  • clnt_call: Makes a remote procedure call using a client handle created by clnt_create.
  • clnt_destroy: Destroys a client handle, closing the RPC connection.
  • rpcinfo: Provides information about RPC services on remote hosts.