Sender: larry@vishnu.eco.twg.com (Lawrence B. Henry III)
Nntp-Posting-Host: eco.twg.com
Reply-To: larry@eco.twg.com
Organization: The Wollongong Group (East Coast Operations)
References: <160@bjcong.bj.co.uk>
Date: Thu, 7 Jan 93 19:21:57 GMT
Lines: 142
In article <160@bjcong.bj.co.uk>, maf@bjcong.bj.co.uk (AUSTIN FARR) writes:
|>
|>ftp on AIX: subcommand errors
|>-----------------------------
|>
|>What is the meaning of the 3-digit numbers in messages relating to ftp (on AIX)
|>subcommands? In particular, how is a failure signalled?
|>
|>The following is an extract from an ftp dialogue:
|>ftp> get absent
|>200 PORT command successful
|>550 absent: No such file or directory
|>ftp> cd tmp
|>250 CWD command successful
|>
|>The leading 3-digit numbers in messages from ftp appear to relate to
|>interactions with the remote machine. A number beginning with '5' appears to
|>signify failure of the operation. If the last message before the 'ftp>' prompt begins with a digit other than '5' - is this a sufficient test for successful
|>completion of the last subcommand?
|>
|>I would be grateful for further information. Please reply by email.
|>Thank you.
|>
Austin,
Check out rfc640.. I believe that this is the latest source of
information on this topic.. it is readily available from nic.ddn.mil in the
RFC sub-directory..
-Larry.
---Excerpt from RFC640 showing response codes for FTP---
There are four values for the first digit of the reply code: 11a
1yz Positive Preliminary reply 11b
The requested action is being initiated; expect another
reply before proceeding with a new command. (The
user-process sending another command before the completion
reply would be in violation of protocol; but server-FTP
processes should queue any commands that arrive while a
preceeding command is in progress.) This type of reply can
be used to indicate that the command was accepted and the
user-process may now pay attention to the data connections,
for implementations where simultaneous monitoring is
difficult. 11b1
2yz Positive Completion reply 11c
The requested action has been successfully completed. A
new request may be initiated. 11c1
3yz Positive Intermediate reply 11d
The command has been accepted, but the requested action is
being held in abeyance, pending receipt of further
information. The user should send another command
specifying this information. This reply is used in command
sequence groups. 11d1
4yz Transient Negative Completion reply 11e
The command was not accepted and the requested action did
not take place, but the error condition is temporary and
the action may be requested again. The user should return
to the beginning of the command sequence, if any. It is
difficult to assign a meaning to "transient", particularly
when two distinct sites (Server and User-processes) have to
agree on the interpretation. Each reply in the 4yz
category might have a slightly different time value, but
the intent is that the user-process is encouraged to try
again. A rule of thumb in determining if a reply fits into
the 4yz or the 5yz (Permanent Negative) category is that
replies are 4yz if the commands can be repeated without any
change in command form or in properties of the User or
Server (e.g. the command is spelled the same with the same
NWG/RFC# 640 JBP NJN 5-JUN-74 16:07 30843
Neigus FTP Reply Codes [5]
arguments used; the user does not change his file access or
user name; the server does not put up a new
implementation.) 11e1
5yz Permanent Negative Completion reply 11f
The command was not accepted and the requested action did
not take place. The User-process is discouraged from
repeating the exact request (in the same sequence). Even
some "permanent" error conditions can be corrected, so the
human user may want to direct his User-process to
reinitiate the command sequence by direct action at some
point in the future (e.g. after the spelling has been
changed, or the user has altered his directory status.) 11f1
The following function groupings are encoded in the second
digit: 11g
x0z Syntax - These replies refer to syntax errors,
syntactically correct commands that don't fit any
functional category, unimplemented or superfluous
commands. 11g1
x1z Information - These are replies to requests for
information, such as status or help. 11g2
x2z Connections - Replies referring to the TELNET and
data connections. 11g3
x3z Authentication and accounting - Replies for the logon
process and accounting procedures. 11g4
x4z Unspecified as yet 11g5
x5z File system - These replies indicate the status of
the Server file system vis-a-vis the requested
transfer or other file system action. 11g6
The third digit gives a finer gradation of meaning in each of
the function categories, specified by the second digit. The
list of replies below will illustrate this. Note that the
text associated with each reply is suggestive, rather than
mandatory, and may even change according to the command with
which it is associated. The reply codes, on the other hand,
should strictly follow the specifications in the last section;
that is, Server implementations should not invent new codes
for situations that are only slightly different from the ones
described here, but rather should adapt codes already defined.
NWG/RFC# 640 JBP NJN 5-JUN-74 16:07 30843
Neigus FTP Reply Codes [6]
If additional codes are found to be necessary, the details
should be submitted to the FTP committee, through Jon Postel. 11h