Net::Cmd(3pm) Perl Programmers Reference Guide Net::Cmd(3pm)
NAME
Net::Cmd - Network Command class (as used by FTP, SMTP etc)
SYNOPSIS
use Net::Cmd;
@ISA = qw(Net::Cmd);
DESCRIPTION
"Net::Cmd" is a collection of methods that can be inherited by a sub
class of "IO::Handle". These methods implement the functionality
required for a command based protocol, for example FTP and SMTP.
USER METHODS
These methods provide a user interface to the "Net::Cmd" object.
debug ( VALUE )
Set the level of debug information for this object. If "VALUE" is
not given then the current state is returned. Otherwise the state
is changed to "VALUE" and the previous state returned.
Different packages may implement different levels of debug but a
non-zero value results in copies of all commands and responses also
being sent to STDERR.
If "VALUE" is "undef" then the debug level will be set to the
default debug level for the class.
This method can also be called as a static method to set/get the
default debug level for a given class.
message ()
Returns the text message returned from the last command
code ()
Returns the 3-digit code from the last command. If a command is
pending then the value 0 is returned
ok ()
Returns non-zero if the last code value was greater than zero and
less than 400. This holds true for most command servers. Servers
where this does not hold may override this method.
status ()
Returns the most significant digit of the current status code. If a
command is pending then "CMD_PENDING" is returned.
datasend ( DATA )
Send data to the remote server, converting LF to CRLF. Any line
starting with a '.' will be prefixed with another '.'. "DATA" may
be an array or a reference to an array.
dataend ()
End the sending of data to the remote server. This is done by
ensuring that the data already sent ends with CRLF then sending
'.CRLF' to end the transmission. Once this data has been sent
"dataend" calls "response" and returns true if "response" returns
CMD_OK.
CLASS METHODS
These methods are not intended to be called by the user, but used or
over-ridden by a sub-class of "Net::Cmd"
debug_print ( DIR, TEXT )
Print debugging information. "DIR" denotes the direction true being
data being sent to the server. Calls "debug_text" before printing
to STDERR.
debug_text ( TEXT )
This method is called to print debugging information. TEXT is the
text being sent. The method should return the text to be printed
This is primarily meant for the use of modules such as FTP where
passwords are sent, but we do not want to display them in the
debugging information.
command ( CMD [, ARGS, ... ])
Send a command to the command server. All arguments a first joined
with a space character and CRLF is appended, this string is then
sent to the command server.
Returns undef upon failure
unsupported ()
Sets the status code to 580 and the response text to 'Unsupported
command'. Returns zero.
response ()
Obtain a response from the server. Upon success the most
significant digit of the status code is returned. Upon failure,
timeout etc., undef is returned.
parse_response ( TEXT )
This method is called by "response" as a method with one argument.
It should return an array of 2 values, the 3-digit status code and
a flag which is true when this is part of a multi-line response and
this line is not the list.
getline ()
Retrieve one line, delimited by CRLF, from the remote server.
Returns undef upon failure.
NOTE: If you do use this method for any reason, please remember to
add some "debug_print" calls into your method.
ungetline ( TEXT )
Unget a line of text from the server.
rawdatasend ( DATA )
Send data to the remote server without performing any conversions.
"DATA" is a scalar.
read_until_dot ()
Read data from the remote server until a line consisting of a
single '.'. Any lines starting with '..' will have one of the '.'s
removed.
Returns a reference to a list containing the lines, or undef upon
failure.
tied_fh ()
Returns a filehandle tied to the Net::Cmd object. After issuing a
command, you may read from this filehandle using read() or <>. The
filehandle will return EOF when the final dot is encountered.
Similarly, you may write to the filehandle in order to send data to
the server after issuing a command that expects data to be written.
See the Net::POP3 and Net::SMTP modules for examples of this.
EXPORTS
"Net::Cmd" exports six subroutines, five of these, "CMD_INFO",
"CMD_OK", "CMD_MORE", "CMD_REJECT" and "CMD_ERROR", correspond to
possible results of "response" and "status". The sixth is
"CMD_PENDING".
AUTHOR
Graham Barr <gbarr AT pobox.com>
COPYRIGHT
Copyright (c) 1995-2006 Graham Barr. All rights reserved. This program
is free software; you can redistribute it and/or modify it under the
same terms as Perl itself.
perl v5.16.3 2023-10-25 Net::Cmd(3pm)