5.3.2 Remote Communication Procedures

‘lib/remote.exp’ defines these functions, for establishing and managing communications:

Procedures to establish a connection: Each of these procedures tries to establish the connection up to three times before returning. Warnings (if retries will continue) or errors (if the attempt is abandoned) report on communication failures. The result for any of these procedures is either -1, when the connection cannot be established, or the spawn ID returned by the expect command spawn.

It use the value of the connect field in the target_info array (was connectmode as the type of connection to make. Current supported connection types are tip, kermit, telnet, rsh, rlogin, and netdata. If the --reboot option was used on the runtest command line, then the target is rebooted before the connection is made.

remote_open type

Remote Connection Procedure. This is passed host or target. Host or target refers to whether it is a connection to a remote target, or a remote host. This opens the connection to the desired target or host using the default values in the configuration system. It returns that spawn_id of the process that manages the connection. This value can be used in expect or exp_send statements, or passed to other procedures that need the connection process’s id. This also sets the fileid field in the target_info array.

remote_close shellid

shellid is value returned by a call to remote_open. This closes the connection to the target so resources can be used by others. This parameter can be left off if the fileid field in the target_info array is set.

telnet hostname port

rlogin hostname

rsh hostname

IP network procedures. hostname refers to the IP address or name (for example, an entry in ‘/etc/hosts’) for this target. The procedure names reflect the Unix utility used to establish a connection. The optional port is used to specify the IP port number. The value of the netport field in the target_info array is used. (was $netport) This value has two parts, the hostname and the port number, seperated by a :. If host or target is used in the hostname field, than the config array is used for all information.

tip port

Serial line procedure. Connect using the Unix utility tip. port must be a name from the tip configuration file ‘/etc/remote’. Often, this is called ‘hardwire’, or something like ‘ttya’. This file holds all the configuration data for the serial port. The value of the serial field in the target_info array is used. (was $serialport) If host or target is used in the port field, than the config array is used for all information.

kermit port bps

Serial line procedure. Connect using the program kermit. port is the device name, e.g. ‘/dev/ttyb’. bps is the line speed to use (in bits per second) for the connection. The value of the serial field in the target_info array is used. (was $serialport) If host or target is used in the port field, than the config array is used for all information.

Procedures to manage a connection:

tip_download spawnid file

Download ‘file’ to the process spawnid (the value returned when the connection was established), using the ~put command under tip. Most often used for single board computers that require downloading programs in ASCII S-records. Returns 1 if an error occurs, 0 otherwise.

exit_remote_shell spawnid

Exits a remote process started by any of the connection procedures. spawnid is the result of the connection procedure that started the remote process.

download file [ spawnid ]

After you establish a connection to a target, you can download programs using this command. download reads in file (object code in S-record format) and writes it to the device controlling this spawnid. (From the point of view of the target, the S-record file comes in via standard input.)

If you have more than one target active, you can use the optional argument spawnid to specify an alternative target (the default is the most recently established spawnid.)