DIGITAL TCP/IP Services for OpenVMS
User's Guide


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1.1.1 Services for Working with Files

FTP allows you to establish a session with the remote host and enter an unlimited number of commands that copy, display, or manipulate files and directories. The Anonymous FTP feature (See Section 2.3.2) allows you to connect to a remote host without specifying user authentication information. If that feature is not enabled, you must supply user authentication information for a remote host only once: when you first establish the FTP connection with the remote host. FTP allows you to determine or change the working directory on your host and on the remote host, and to perform various other operations on files and directories.

In contrast, RCP is limited to copying files. To copy files, each RCP command that you enter establishes a separate link for each file transfer with the specified remote host. With each RCP command, you must specify the remote host to or from which you want to copy files. As with FTP, RCP has a feature that allows you to connect to remote hosts without specifying user authentication information. However, if that feature is not enabled, you must enter user authentication information with each RCP command, rather than just once (as with FTP) for any number of subsequent commands for a connected host.

1.1.2 Services for Remote Logins

The RLOGIN, TELNET, and TN3270 facilities each allow you to log in to a remote host and enable your terminal to perform as if directly connected to the remote host. Use RLOGIN for simple logins in which you do not require much customization or control of the terminal-to-host interaction. Use TELNET if you want to use its extensive terminal features and controls, or you want to open several terminal sessions with one or more remote hosts. With TELNET's extensive functionality, it can support a wider variety of terminal features and behaviors between disparate, otherwise incompatible, systems.

Use TN3270 to connect your terminal to a remote host that supports IBM 3270 IDS terminals. TN3270 assigns IBM 3270 functions to your DIGITAL keyboard and allows you to redefine keys.

1.1.3 Services for Issuing Commands at a Remote Host

RSH and REXEC allow you to send any commands supported by the remote host operating system. RSH and REXEC issue one command per link. If user authentication is required, you must enter the authentication information with each command. There is no REXEC command. You invoke REXEC when you enter the RSH command with a password (RSH/PASSWORD).

Note that RLOGIN, TELNET, and TN3270 allow you to log in to a remote host once and then perform any number of commands supported by the remote host's operating system. TELNET and TN3270 also allow you to send certain commands to the connected remote host during a terminal session; however, these are a limited range of commands dealing with communication between hosts. They are not operating system commands. For example, you can send a command that aborts output or interrupts execution of a command you entered previously.

1.2 Client/Server Software

The user services include client and server software that communicates between host systems. Your local host includes client software that responds to your commands by requesting the appropriate services from the remote host you specify. If the remote host has the appropriate server software, the server on that host responds with the requested service.

For example, Figure 1-1 shows the interplay between the FTP local client and remote server. The FTP client software requests the FTP server software on Host B to open a connection.

Figure 1-1 FTP Client/Server Software Interacting


  1. User MILTON enters an FTP CONNECT command from local host Host A to connect to remote host Host B.
  2. The FTP local client sends a connection request to the FTP server on Host B.
  3. The remote server grants the request, sending a data connection status message back to the local client.
  4. The client displays at user MILTON's terminal the server connection status message and the remote host prompt for login information.

Once the connection is made, user MILTON can then log onto the remote system and use FTP to copy files and perform other related services. Note that both server and client software exist on each system supporting FTP. Thus, a user on Host B could connect to Host A and copy files back and forth from Host B.

1.3 User Commands

The FTP, TELNET, and TN3270 components include a wider variety of commands than do the other user services.

You can start FTP, TELNET, or TN3270 and connect to a remote host interactively in either of two ways:

In either case, you are prompted for user authentication information. (FTP includes a feature that allows you to connect to a remote host without specifying user authentication information (See Section 2.3.2).) You can also start these utilities by using a command procedure.

Start the Remote (R) and network printer services by specifying the appropriate command, host name, and parameters or qualifiers in one command line. If you specify the service command only (RCP, RSH, RLOGIN, PRINT, LPQ, or LPRM), the service prompts you for the information required for the command. The PRINT command supports remote printing using TCP/IP protocols and supporting the DCL PRINT qualifiers, with a few exceptions and additional features, as explained in Section 6.1.

When you enter the FINGER command without any host or user information, the service displays information about users on your local system. To display information about remote users, you need to specify the remote host name. For more details and options, see Chapter 7.

To start MAIL and then send a message to a user on another internet host, simply start the OpenVMS Mail utility as you normally do, and use the SEND command with the Internet address of the remote host, such as in the following example. The Mail utility will use the SMTP protocol to send the mail. (See Chapter 5 for details about exceptions and alternatives.)


$ MAIL
MAIL> send [Return]
To:     MALCOLM@PHILOS.BU.ORG [Return]
Subj:   FINAL EXAMS[Return]

1.4 Command Syntax

Use the following rules when you type a command line:

1.5 Online Help

You can access most of the introductory material in this manual on line by entering:


$ HELP TCPIP_Services 

Options under this heading include introductory information about the following TCP/IP services:


$ HELP TCPIP_Services 
 
  Additional information available: 
 
  Product_Overview      BIND       BOOTP      DHCP       TFTP       NTP 
  SNMP       NFS        SLIP_and_PPP          Management_Tools 
  UNIX_Commands         Routing    Command_Syntax        NSLOOKUP 
  Programming_Interfaces           Finger     FTP        SMTP       POP 
  LPR_LPD    Remote_Commands       TELNET     RPCGEN 

In addition to this overview information, you can access help on a number of specific TCP/IP commands directly at the DCL prompt by typing any of the following:


 
$ HELP FINGER
$ HELP FTP
$ HELP LPQ
$ HELP LPRM
$ HELP PRINT
$ HELP RCP
$ HELP REXEC
$ HELP RLOGIN
$ HELP RSH
$ HELP TELNET
$ HELP TN3270

Because TELNET, FTP, and the management commands generate their own system prompts, you need to go to their prompts to get help with specific commands:


Chapter 2
Working with Files Using File Transfer (FTP)

The DIGITAL TCP/IP Services for OpenVMS software includes the File Transfer Protocol (FTP) service. The FTP Protocol allows the transferring of data between hosts that use dissimilar file systems. The FTP command is the interface to the File Transfer Protocol and provides commands to:

FTP does not allow recursive copying. You can use the RCP command, if you need this function.

What You Need

To use FTP, you need the following:

What You Can Do

The following table lists the FTP file services and the sections that explain how to use them.
Capability Section
Enter either DCL-style or UNIX style command syntax 2.1
Customize the way FTP processes commands and file transfers 2.13
2.14.2
Display all FTP commands sent to the remote host during command processing 2.13
Display all replies from the remote host during command processing 2.13
Gain access to OpenVMS files without specifying your user name or a password 2.3.2
Use either OpenVMS or UNIX command syntax in command procedures that use FTP 2.14
Set and display the default (working) directory on the local or remote host 2.6
Create and delete remote directories 2.7
View remote directories 2.5
Delete a remotefile 2.9
Rename a remote file 2.9
Append a local file to a remote file 2.11
Display the contents of a file on a remote host 2.10
Copy files from a connected remote host to your local host 2.8.1
Copy files from your local host to the connected remote host 2.8.2
Preserve OpenVMS file attributes when copying files to a UNIX system and back again 2.8.5
Copy files to and from a DECnet node 2.15
Suspend FTP to spawn a subprocess at the DCL prompt 2.12

Command Summary

To use FTP, enter the commands summarized in Table 2-1 (for complete command descriptions see Section 2.16).

Table 2-1 FTP Commands: Summary
DCL-Style Command Equivalent
UNIX Style Command
Description
Starting and Exiting (At the DCL Prompt)
FTP ftp Invokes FTP
FTP remote_host ftp remote_host Invokes FTP and establishes a connection to a remote host
Starting and Exiting (At the FTP> Prompt)
CONNECT open Establishes a connection to a remote host
DISCONNECT close Closes the connection with the remote host
EXIT
Ctrl/Z
quit Closes the connection with the remote host and exits FTP
Sending Commands to the Remote Host
APPEND append Concatenates a local file to a remote file
CREATE/DIRECTORY mkdir Creates a remote directory
DELETE delete
mdelete
Deletes remote files
DIRECTORY ls Lists remote file names and related information
GET get
mget
Copies files from the remote host to the local host
LOGIN user Logs you in to a remote host
PUT put
mput
Copies files from the local host to the remote host
RENAME rename Changes file name(s) on remote systems
SET DEFAULT cd
lcd
Sets the remote working directory or the local working directory
SHOW DEFAULT pwd
lpwd
Displays the name of the remote current working directory or the local working directory
VIEW view Displays the contents of a file on the current output device
Suspending FTP to Return to DCL Prompt
SPAWN ! Suspends FTP to create a subprocess at the local DCL prompt
Customizing Your Session's Environment
DISABLE LOG debug+ Disables the display of all the protocol commands sent to the remote host
DISABLE PARSE glob+ Disables the expansion of file names
DISABLE
PORT_COMMAND
sendport+ Disables the sending of the FTP protocol PORT command
DISABLE REPLY N/A Disables the display of all responses from the remote host
DISABLE
TRANSFER_VERIFICATION
hash+ Disables the display of # for each 1K bytes of data transferred
DISABLE
VMS_PLUS
N/A Disables the special OpenVMS-to-OpenVMS transfer mode
ENABLE LOG debug+ Enables the display of protocol commands sent to the remote host
ENABLE PARSE glob+ Enables the expansion of file names
ENABLE
PORT_COMMAND
sendport+ Enables the sending of the FTP protocol PORT command
ENABLE REPLY N/A Enables the display of responses from the remote host
ENABLE
TRANSFER_VERIFICATION
hash+ Enables the display of # for each 1K bytes of data transferred
ENABLE
VMS_PLUS
N/A Enables the special OpenVMS-to-OpenVMS transfer mode
HELP ? Invokes help
QUOTE quote Sends FTP commands to the remote host without local interpretation
SET TYPE type Defines the data representation for file transfers
SHOW STATUS status Displays the current FTP parameter settings and, if you have an open connect, the name of the connected host
SPAWN ! Starts up a subprocess at the DCL prompt


+This command toggles the value between enabled and disabled.


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