ftp.1c

<B>Digital的Unix操作系统VAX 4.2源码</B>

.IR outchars .
If the character's position in
.I inchars
is longer than the length of
.IR outchars ,
the character is deleted from the file name.
.RE
.TP 10
\fBopen\fP \fIhost\fP [ \fIport\fP ]
.NXR "open command (ftp)"
Establishes a connection to the specified
host
.PN ftp
server.  If an optional port number is supplied,
.PN ftp
attempts to contact an 
.PN ftp
server at that port.
If the 
.I auto-login
option is on (the default), 
.PN ftp
automatically attempts to log the user in to
the
.PN ftp
server (see the description of the \f(CW.netrc\fR file).
.TP
.B prompt
.NXR "prompt command (ftp)"
Toggles interactive prompting.  Interactive prompting
occurs during multiple file transfers to allow the
user to retrieve or store files selectively.  If
prompting is turned off (the default), any
.B mget
or
.B mput
transfers all files.
.TP
\fBproxy\fP \fIftp-command\fP
.NXR "proxy command (ftp)"
Executes an 
.PN ftp
command on a secondary control connection.
This command allows simultaneous connection to two remote 
.PN ftp
servers for transferring files between the two servers.
The first
.B proxy
command should be an
.BR open ,
to establish the secondary control connection.
Type the command
.PN proxy\0? 
to see other 
.PN ftp
commands executable on the
secondary connection.
The following commands behave differently when prefaced by
.BR proxy :
.IP
.B open
does not define new macros during the auto-login process.
.IP
.B close
does not erase existing macro definitions.
.IP
.B get
and
.B mget
transfer files from the host on the primary control connection
to the host on the secondary control connection.
.IP
.BR put ,
.BR mput ,
and
.B append
transfer files from the host on the secondary control connection
to the host on the primary control connection.
Third-party file transfers depend upon support of the FTP
PASV command by the server on the secondary control connection.
.TP
\fBput\fP \fIlocal-file\fP [ \fIremote-file\fP ]
.NXR "put command (ftp)"
Copies a local file to the remote machine.  If you do not
specify a
.IR remote-file ,
the local file name is used
to name the remote file.  File transfer uses the
current settings for
.IR type ,
.IR format ,
.IR mode ,
and
.IR structure .
.TP
.B pwd
.NXR "pwd command (ftp)"
Prints the name of the current working directory on the remote
machine.
.TP
.B quit
.NXR "quit command (ftp)"
A synonym for 
.BR bye .
.TP
.BI quote " arg1 arg2 ..."
.NXR "quote command (ftp)"
Sends the arguments that are specified, verbatim, to the remote
.PN ftp
server.  A single FTP reply code is expected in return.
.TP
\fBrecv\fP \fIremote-file\fP [ \fIlocal-file\fP ]
.NXR "recv command (ftp)"
A synonym for 
.BR get .
.TP
\fBremotehelp\fP [ \fIcommand-name\fP ]
.NXR "remotehelp command (ftp)"
Requests help from the remote
.PN ftp
server.  If a 
command name
is specified, it is supplied to the server as well.
.TP
\fBrename\fP [ \fIfrom\fP ] [ \fIto\fP ]
.NXR "rename command (ftp)"
Renames the file
.I from
on the remote machine to the file
.IR to .
.TP
.B reset
.NXR "reset command (ftp)"
Clears the reply queue.
This command resynchronizes command/reply sequencing with the remote
.PN ftp
server.  If the remote server violates FTP,
resynchronization may be necessary.
.TP
.BI rmdir " directory-name"
.NXR "rmdir command (ftp)"
Deletes a directory on the remote machine.
.TP
.B runique
.NXR "runique command (ftp)"
Toggles storing of files on the local system with unique file
names.
If a file already exists with a name equal to the target
local file name for a
.B get
or
.B mget
command, a .1 is appended to the name.
If the resulting name matches another existing file,
a .2 is appended to the original name.
If this process continues up to .99, an error
message is printed, and the transfer does not take place.
The generated unique file name will be reported.
Note that
.B runique
will not affect local files generated from a shell command
(see below).
The default value is off.
.TP
\fBsend\fP \fIlocal-file\fP [ \fIremote-file\fP ]
.NXR "send command (ftp)"
A synonym for 
.BR put .
.TP
.B sendport
.NXR "sendport command (ftp)"
Toggles the use of PORT commands.  By default, 
.PN ftp
attempts to use a PORT command when establishing
a connection for each data transfer.  If the PORT
command fails, 
.PN ftp
uses the default data port.  When the use of PORT
commands is disabled, no attempt is made to use
PORT commands for each data transfer.  This is useful
for certain FTP implementations that do ignore PORT
commands but, incorrectly, indicate that the commands
have been accepted.
.TP
.B status
.NXR "status command (ftp)"
Shows the current status of
.PN ftp .
.TP
\fBstruct\fP [ \fIstruct-name\fP ]
.NXR "struct command (ftp)"
Sets the file transfer structure to
.IR struct-name .
By default the file structure is used.
.TP
.B sunique
.NXR "sunique command (ftp)"
Toggles storing of files on a remote machine under unique file names.
The remote 
.PN ftp
server must support the FTP STOU command for
successful completion of this command.
The remote server reports the unique name.
The default value is off.
.TP
.B tenex
Sets the file transfer type to that needed to
talk to TENEX machines.
.TP
.B trace
.NXR "trace command (ftp)"
Toggles packet tracing.
.TP
\fBtype\fP [ \fItype-name\fP ]
.NXR "type command (ftp)"
Sets the file transfer
.I type
to
.IR type-name .
If no type is specified, the current type
is printed.  The default type is network ASCII.
.TP
\fBuser\fP \fIuser-name\fP [ \fIpassword\fP ] [ \fIaccount\fP ]
.NXR "user command (ftp)"
Identifies you to the remote
.PN ftp
server.  If the
password is not specified and the server requires it,
.PN ftp
disables the local echo and then prompts you for it.
If an account field is not specified, and the
.PN ftp
server
requires it, you are prompted for it also.  Unless
.PN ftp
is invoked with auto-login disabled, this
process is done automatically on initial connection to
the
.PN ftp
server.
.TP
.B verbose
.NXR "verbose command (ftp)"
Toggles the verbose mode.  In verbose mode, all responses from
the
.PN ftp
server are displayed.  In addition,
if verbose is on, statistics
regarding the efficiency of a file transfer are reported when
the transfer is complete.  By default,
verbose is on.
.SS Aborting a File Transfer
To abort a file transfer, use the terminal interrupt key
(usually CTRL/C).
Sending transfers are halted immediately.
Receiving transfers are halted by sending an FTP ABOR
command to the remote server, and discarding any further data received.
The speed at which this is accomplished depends on the remote
server's support for ABOR processing.
If the remote server does not support the ABOR command, an 
.PN ftp>
prompt appears when the remote server has completed
sending the requested file.
.PP
The terminal interrupt key sequence is ignored when
.PN ftp
has completed any local processing and is awaiting a reply
from the remote server.
A long delay in this mode may result from ABOR processing,
or from unexpected behavior by the remote server, including
violations of the FTP.
If the delay results from unexpected remote server behavior, the local
.PN ftp
program must be killed by hand.
.SS File-Naming Conventions
.NXR "ftp program" "file-naming conventions"
Files specified as arguments to
.PN ftp
commands are processed according to the following rules:
.TP 4
1)
Standard input is used for reading
and standard output is used for writing
when the file name is specified as a minus sign (\-).
.TP
2)
If the first character of the file name is a vertical bar
(|), the
remainder of the argument is interpreted as a shell command.
The
.PN ftp
command
then forks a shell, using
.MS popen 3
with the argument supplied, and reads or writes from standard
output
or standard input respectively.  
If the shell command includes spaces, the argument
must be quoted, as in 
\f(CW"|ls -lt"\fR.
A particularly
useful example of this mechanism is: 
\f(CW"dir\0|more"\fR.
.TP
3)
If globbing is enabled, 
local file names are expanded
according to the rules used in the 
.MS csh 1   
(compare to the
.PN glob
command).
If the
.PN ftp
command expects a single local file, such as 
.BR put ,
only the first file name generated by the globbing operation is used.
.TP
4)
For
.B mget
commands and
.B get
commands with unspecified local file names, the local file name is
the remote file name and can be altered by a
.BR case ,
.BR ntrans ,
or
.B nmap
setting.
The resulting file name may then be altered if
.B runique
is on.
.TP
5)
For
.B mput
commands and
.B put
commands with unspecified remote file names, the remote file name is
the local file name and can be altered by a
.B ntrans
or
.B nmap
setting.
The resulting file name can then be altered by the remote server if
.B sunique
is on.
.SS File Transfer Parameters
.NXR "ftp program" "parameters supported"
Many parameters can affect a file transfer.  The 
.I type
can be 
.BR ascii , 
.B image
(binary),
.BR ebcdic ,
or local byte size.
The
.PN ftp
command supports the
.B ascii
 and
.B image
types of file transfer and local 
byte size 8 for tenex mode transfers.
.PP
The
.PN ftp
command supports only the default values for the remaining
file transfer parameters: 
.IR mode ,
.IR form ,
and
.IR struct .
.SS The \&.netrc File
The \f(CW.netrc\fR
file contains login and initialization information
used by the 
.PN ftp
auto-login process.
It resides in your home directory.
See
.MS netrc 5
for a description and example of a \f(CW.netrc\fR
file.
The following tokens in the \f(CW.netrc\fR
file are recognized; 
they can be separated by spaces,
tabs, or new-lines:
.TP 10
\fBmachine\fP \fIname\fP
Identifies a remote machine name.
The auto-login process searches the \f(CW.netrc\fR file for a
.B machine
token that matches the remote machine specified on the
.PN ftp
command line or as an
.B open
command argument.
Once a match 
.ne 2
is made, the subsequent \f(CW.netrc\fR tokens are processed,
stopping when the end of file is reached or another
.I machine
token is encountered.
.TP
\fBlogin\fP \fIname\fP
Identifies a user on the remote machine.
If this token is present, the auto-login process initiates
a login using the specified name.
.TP
\fBpassword\fP \fIstring\fP
Supplies a password.
If this token is present, the auto-login process supplies the
specified string if the remote server requires a password as part
of the login process.
Note that if this token is present in the \f(CW.netrc\fR file,
and if the \f(CW.netrc\fR is readable by
anyone other than the user,
.PN ftp
aborts the auto-login process.
.TP
\fBaccount\fP \fIstring\fP
Supplies an additional account password.
When this token is present, the auto-login process supplies the
the remote server with 
an additional account password if the remote server requires it.
If it does not, the auto-login process initiates an
ACCT command.
.TP
\fBmacdef\fP \fIname\fP
Defines a macro.
This token functions like the
.PN ftp
.B macdef
command.
A macro is defined with a specified name; its contents begin with the
next \f(CW.netrc\fR line and continue until a null line (consecutive new-line
characters) is encountered.
If a macro named
.I init
is defined, it is automatically executed as the last step in the
auto-login process.
.SH Restrictions
.NXR "ftp program" "restricted"
Correct execution of many commands depends on proper behavior by the 
remote server.
.PP
The 
.PN ftpd
server prevents the unauthorized users listed in 
the 
.PN /etc/ftpusers
file from transferring files.
.PP
An error in the treatment of carriage returns in the 4.2BSD UNIX 
.BR ascii type
transfer code has been corrected.  This correction may result in
incorrect transfers of binary files to and from 4.2BSD servers using 
the 
.B ascii
type.  Avoid this problem by using the
.B binary
image type.
.SH Files
.TP 20
.PN /etc/ftpusers
Contains the list of unauthorized users 
.SH See Also
netrc(5), services(5), ftpd(8c), inetd(8c), syslog(8)