rexec()

The rexec() call allows command processing on a remote host.

Syntax

#include <utils.h>
int rexec(host, port, user, passwd, cmd, err_sd2p)
char **host;
int port;
char *user, *passwd, *cmd;
int *err_sd2p;

Parameters

host

Contains the name of a remote host that is listed in the ETC\HOSTS file or ETC\RESOLV file. If the name of the host is not found in either file, the rexec() call is unsuccessful.

Specifies the well-known internet port to use for the connection. A pointer to the structure that contains the necessary port can be obtained by issuing the following library call:

getservbyname("exec","tcp")

When directly specifying an integer for the port, specify it in Network Byte order, obtainable by using the htons() function call.

Points to a user ID valid at the remote host.

Points to a password valid at the remote host.

Points to the name of the command to be processed at the remote host.

Points to an error socket descriptor. An auxiliary channel to a control process is set up, and a descriptor for it is placed in the err_sd2p parameter. The control process provides diagnostic output from the remote command on this channel. This diagnostic information does not include remote authorization failure, since this connection is set up after authorization has been verified.

Description

The rexec() call allows the calling process to start commands on a remote host.

If the rexec() connection succeeds, a socket in the internet domain of type SOCK_STREAM is returned to the calling process and is given to the remote command as standard input and standard output.

Return Values

When successful, the call returns a socket to the remote command.

When unsuccessful, the call returns a value of -1, indicating that the specified host name does not exist.

Examples

int normsock;char *host = NULL, *luser = NULL, *password = NULL, *cmd;
struct servent *sp;
sp = getservbyname("exec", "tcp");

host = "remote _host";
luser = "my _userid";
password = "my _password";
cmd = "rempte_host_cmd";

normsock = rexec(&host, sp->s_port, luser,password, cmd, &errsock);
if (normsock == -1)
       exit(-1);

Related Calls

getservbyname()