I am facing a problem .The problem is in my shell script i am fetching some file from a remote machine by writing a script for GET.after getting a file from a remote machine i am closing the connection because i will do some operations on the file received .after successfully completing the operations i am supposed to delete the files from the remote machine.so how do u know that these are the files on which the operation was successful and now i will have to delete those files from the remote machine .all the operations will be written in a single script.
Thanks in advance.
Perhaps this can help you.
During ftp execution, you can invoque a shell script, as follows:
Another option is to use a rsh o rexec programs and may compare the two files on both hosts.
this is the basic syntaxis:
rexec host service [parameters]
Thanks for ur reply .By the way can u elaborate on the script comparefiles.sh.Basically what actually is there inside this particular comparefiles.sh code.
Thanks in advance
Hi, you told me "after get the file, I have to do something with it." This is your program, and my program is the same, do you follow me?
So your program have to do this in this sequence:
first, have to do all the operations that you've mentioned including getting the remote file using a macro ftp,
second, if the result of your operations is fine (by example asking about the process status (if [ $? -eq 0 ]), then you must to delete the remote file. You have to replace my process with your own system operator's process.
# first get the remote file using your macro ftp command.
# second do what you need to do with your local file.
# then, if the result of the previous step is OK, delete the remote file.
if [ result -eq 0 ]
rexec remote_host remote comand [ parameters ]
the next is the content of the man rexec.
rexec -- execute a service remotely through REXEC
rexec host service [parameters]
rx host command
service host [parameters]
rexec is the REXEC command that allows the user on a client machine to
execute a service on a remote host. A user on a client machine can
utilize any service on the host, provided the user is authorized to
access the service.
Although any service can be installed, REXEC generally provides the
following standard services:
A remote command execution service, which allows the user to
execute any command (provided the user has appropriate
permissions) on the remote host. Any arguments required by the
remote command need to be specified on the rx command line.
A remote login service, which effectively logs the user into
the remote host, bypassing the login/password sequence.
A service that lets the user query a remote host for a list of
services that the user is allowed to execute.
The arguments to the REXEC commands have the following meanings:
The name of the remote host on which the service is defined.
The name of the service to be executed on the remote host.
Service arguments (that is, options or option operands).
The command to be executed remotely, including applicable
When the REXEC software is installed on the client machine, the
standard services are linked to the rexec command. Once linked, the
user can execute a service by specifying the service name, followed by
the host name and the parameters to the service.
The user on the client machine can pass environment variables to a
service by setting the RXPORT variable. RXPORT contains a
comma-separated list of exported variables. Only exported variables
from the user's environment can be passed to the specified service. If
RXPORT only consists of the special character `` * '', then all
exported variables on the local system are passed to the remote
service. By default, the remote service environment includes the
variables PATH and HOME.
rexec requires that tirdwr has been pushed onto the stream. If it has
not, then rexec will exit and log a message in /usr/adm/log/rexec.log.
If it has then execution will continue.
If a user wants to see who is logged into the remote host strider, the
following command can be used:
rexec strider rx who
If rexec is linked to rx, the user can execute the following:
rx strider who
If a user wants to execute the vi(1) command on the remote host aslan,
passing the environment variables TERM and EXINIT to the server, the
user can execute the following:
RXPORT=TERM,EXINIT rx aslan vi main.c
rxlist(1Mtcp), rxservice(1Mbnu), rexecve(3N)
5 November 1999
� 1999 The Santa Cruz Operation, Inc. All rights reserved.
UnixWare 7 Release 7.1.1 - 5 November 1999
See also rexec(3N)
the next is the result of man ftp.
ftp -- file transfer program
ftp [-c | -C] [-dginptv] [host [port]]
The ftp command is the user interface to the ARPANET standard File
Transfer Protocol (FTP). ftp allows you to transfer files to and from
sites on remote networks.
Options may be specified at the command line, or to the command
Suppress the SYST message. This option is used to avoid
crashing a remote server which does not process this message
and cannot deal with unknown messages. If the first command
after FTP login results in the message remote server has closed
connection, you should add the -c option to the ftp command
line and retry the request.
Force ftp to send the SYST message. This is the default action
Enable debugging. See the description of the debug command.
Disable file name globbing. See the description of the glob
Turn off interactive prompting during multiple file transfers.
See the description of the prompt command.
Restrain ftp from attempting ``auto-login'' upon initial
connection. If auto-login is enabled, ftp will check the .netrc
file in the user's home directory for an entry describing an
account on the remote machine. If no entry exists, ftp will
prompt for the remote machine login name (default is the user
identity on the local machine), and, if necessary, prompt for a
password and an account with which to login (see netrc(4tcp)).
Enable passive mode. Forces the ftp server to send a port
number, so that the ftp client can use this port number to
establish a connection to the server. This option is used on
ftp clients with firewalls configured to disallow incoming
calls to random port numbers. See the description of the
Enable packet tracing. See the description of the trace
Verbose on. Forces ftp to show all responses from the remote
server, as well as report on data transfer statistics.
Normally, this is on by default, unless the standard input is
not a terminal. See the description of the trace command.
The client host with which ftp is to communicate may be specified on
the command line. If this is done, ftp immediately attempts to
establish a connection to an FTP server on that host; otherwise, ftp
will enter its command interpreter and await instructions from the
user. If a port number is specified in addition to host, ftp will
attempt to contact an FTP server at that port.
While awaiting commands from the user, ftp displays the prompt ftp>.
The following commands are recognized by ftp. Command arguments which
have embedded spaces may be quoted with quote (") marks.
! [ command [ args ] ]
Invoke an interactive shell on the local machine. If there are
arguments, the first is taken to be a command to execute
directly, with the rest of the arguments as its arguments.
? [ command ]
A synonym for help.
$ macro-name [ args ]
Execute the macro macro-name that was defined with the macdef
command. Arguments are passed to the macro unglobbed.
account [ passwd ]
Supply a supplemental password required by a remote system for
access to resources once a login has been successfully
completed. If no argument is included, the user will be
prompted for an account password in a non-echoing input mode.
append local-file [ remote-file ]
Append a local file to a file on the remote machine. If
remote-file is left unspecified, the local file name is used in
naming the remote file after being altered by any ntrans or
nmap setting. File transfer uses the current settings for type,
format, mode, and structure.
Set the file transfer type to network ASCII. This is the
default type if the remote system does not identify itself as a
Arrange that a bell be sounded after each file transfer command
Set the file transfer type to support binary image transfer.
This is the default type if the remote system identifies itself
as a UNIX system.
Terminate the FTP session with the remote server and exit ftp.
An end of file will also terminate the session and exit.
Toggle remote computer file name case mapping during mget
commands. When case is on (default is off), remote computer
file names with all letters in upper case are written in the
local directory with the letters mapped to lower case.
Change the current directory on the remote machine to
Change the remote machine current directory to the parent of
the current remote machine current directory.
chmod [ mode ] [ remote-file ]
Change file permissions of remote file.
Terminate the FTP session with the remote server, and return to
the command interpreter. Any defined macros are erased.
Toggle carriage return stripping during ascii type file
retrieval. Records are denoted by a carriage return/linefeed
sequence during ascii type file transfer. When cr is on (the
default), carriage returns are stripped from this sequence to
conform with the UNIX single linefeed record delimiter. Records
on non-UNIX remote systems may contain single linefeeds; when
an ascii type transfer is made, these linefeeds may be
distinguished from a record delimiter only when cr is off.
Delete the file remote-file on the remote machine.
debug [ debug-value ]
Toggle debugging mode. If an optional debug-value is specified
it is used to set the debugging level. When debugging is on,
ftp prints each command sent to the remote machine, preceded by
dir [ remote-directory [ local-file ] ]
Print a listing of the directory contents in the directory,
remote-directory, and, optionally, placing the output in
local-file. If interactive prompting is on, ftp will prompt the
user to verify that the last argument is indeed the target
local file for receiving dir output. If no directory is
specified, the current directory on the remote machine is used.
If no local file is specified, or local-file is ``-'', output
comes to the terminal.
A synonym for close.
Set the file transfer form to format. The default and only
supported format is file.
get remote-file [ local-file ]
Retrieve the remote-file and store it on the local machine. If
the local file name is not specified, it is given the same name
it has on the remote machine, subject to alteration by the
current case, ntrans, and nmap settings. The current settings
for type, form, mode, and struct are used while transferring
Toggle filename expansion for mdelete, mget and mput. If
globbing is turned off with glob, the file name arguments are
taken literally and not expanded. Globbing for mput is done as
in sh(1). For mdelete and mget, each remote file name is
expanded separately on the remote machine and the lists are not
merged. Expansion of a directory name is likely to be different
from expansion of the name of an ordinary file: the exact
result depends on the foreign operating system and ftp server,
and can be previewed by doing mls remote-files -. Note that
mget and mput are not meant to transfer entire directory
subtrees of files. That can be done by transferring a tar(1)
archive of the subtree (in binary mode).
Toggle hash-sign (#) printing for each data block transferred.
The size of a data block is BUFSIZ bytes. BUFSIZ is defined in
help [ command ]
Print an informative message about the meaning of command. If
no argument is given, ftp prints a list of the known commands.
Get the inactivity timeout period defined on the server, or try
to set the value of the timeout period on the server to
seconds. You will not be able to set the timeout period to a
value that is larger than the maximum timeout period defined on
Same as binary.
lcd [ directory ]
Change the current directory on the local machine. If no
directory is specified, the user's home directory is used.
ls [ remote-directory [ local-file ] ]
Print an abbreviated listing of the contents of a directory on
the remote machine. The listing includes any system-dependent
information that the server chooses to include; for example,
most UNIX systems will produce output from the command ls -l
(see also nlist). If remote-directory is left unspecified, the
current directory is used. If interactive prompting is on, ftp
will prompt the user to verify that the last argument is indeed
the target local file for receiving ls output. If no local file
is specified, or if local-file is ``-'', the output is sent to
the terminal. Additional options may be specified by quoting
the arguments. For example, ls "-rt dir", will cause a time
sorted listing of directory dir to be displayed if the remote
operating system is UNIX.
Define a macro. Subsequent lines are stored as the macro
macro-name; a null line (consecutive newline characters in a
file or carriage returns from the terminal) terminates macro
input mode. There is a limit of 16 macros and 4096 total
characters in all defined macros. Macros remain defined until a
close command is executed. The macro processor interprets ``$''
and ``\'' as special characters. A ``$'' followed by a number
(or numbers) is replaced by the corresponding argument on the
macro invocation command line. A ``$'' followed by an ``i''
signals that macro processor that the executing macro is to be
looped. On the first pass ``$i'' is replaced by the first
argument on the macro invocation command line, on the second
pass it is replaced by the second argument, and so on. A ``\''
followed by any character is replaced by that character. Use
the ``\'' to prevent special treatment of the ``$''.
mdelete [ remote-files ]
Delete the remote-files on the remote machine.
mdir remote-files local-file
Like dir, except multiple remote files may be specified. If
interactive prompting is on, ftp will prompt the user to verify
that the last argument is indeed the target local file for
receiving mdir output.
Expand the remote-files on the remote machine and do a get for
each file name thus produced. See glob for details on the
filename expansion. Resulting file names will then be processed
according to case, ntrans, and nmap settings. Files are
transferred into the local current directory, which can be
changed with lcd directory; new local directories can be
created with ! mkdir directory.
Make a directory on the remote machine.
mls remote-files local-file
Like nlist, except multiple remote files may be specified, and
the local-file must be specified. If interactive prompting is
on, ftp will prompt the user to verify that the last argument
is indeed the target local file for receiving mls output.
mode [ mode-name ]
Set the file transfer mode to mode-name. The default and only
supported mode-name is stream.
Show the last modification time of the file on the remote
Expand wild cards in the list of local files given as arguments
and do a put for each file in the resulting list. See glob for
details of filename expansion. Resulting file names will then
be processed according to ntrans and nmap settings. The mput
command does not allow specifying remote file names.
newer remote-file [ local-file ]
Get file if remote-file is newer than local-file.
nlist [ remote-directory [ local-file ] ]
Print a list of the files of a directory on the remote machine.
If remote-directory is left unspecified, the current directory
is used. If interactive prompting is on, ftp will prompt the
user to verify that the last argument is indeed the target
local file for receiving nlist output. If no local file is
specified, or if local-file is ``-'', the output is sent to the
Additional options may be specified by quoting the arguments.
For example, nlist "-rt dir" will cause a time sorted listing
of directory dir to be displayed.
nmap [ inpattern outpattern ]
Set or unset the filename mapping mechanism. If no arguments
are specified, the filename mapping mechanism is unset. If
arguments are specified, remote filenames are mapped during
mput commands and put commands issued without a specified
remote target filename. If arguments are specified, local
filenames are mapped during mget commands and get commands
issued without a specified local target filename. This command
is useful when connecting to a non-UNIX remote computer with
different file naming conventions or practices. The mapping
follows the pattern set by inpattern and outpattern. inpattern
is a template for incoming filenames (which may have already
been processed according to the ntrans and case settings).
Variable templating is accomplished by including the sequences
``$1, $2, ..., $9'' in inpattern. Use ``\'' to prevent this
special treatment of the ``$'' character. All other characters
are treated literally, and are used to determine the nmap
inpattern variable values. For example, given
inpattern=``$1.$2'' and the remote file mydata.data $1 would
have the value ``mydata'', and $2 would have the value
``data''. The outpattern determines the resulting mapped
filename. The sequences ``$1, $2, ...., $9'' are replaced by
any value resulting from the inpattern template. The sequence
``$0'' is replaced by the original filename. Additionally, the
sequence ``[seq1,seq4]'' is replaced by seq1 if seq1 is not a
null string; otherwise it is replaced by seq2. For example, the
command nmap $1.$2.$3 [$1,$2].[$2,file] would yield the output
filename ``myfile.data'' for input filenames ``myfile.data''
and ``myfile.data.old'' ``myfile.file'' for the input filename
``myfile'' and ``myfile.myfile'' for the input filename
``.myfile''. Spaces may be included in outpattern, as in the
example: nmap $1 |sed "s/ *$//" > $1 . Use the ``\'' character
to prevent special treatment of the ``$'', ``['', ``]'', and
ntrans [ inchars [ outchars ] ]
Set or unset the filename character translation mechanism. If
no arguments are specified, the filename character translation
mechanism is unset. If arguments are specified, characters in
remote filenames are translated during mput commands and put
commands issued without a specified remote target filename. If
arguments are specified, characters in local filenames are
translated during mget commands and get commands issued without
a specified local target filename. This command is useful when
connecting to a non-UNIX remote computer with different file
naming conventions or practices. Characters in a filename
matching a character in inchars are replaced with the
corresponding character in outchars. If the character's
position in inchars is longer than the length of outchars, the
character is deleted from the file name.
open host [ port ]
Establish a connection to the specified host FTP server. An
optional port number may be supplied, in which case, ftp will
attempt to contact an FTP server at that port. If auto-login is
enabled (default), ftp will also attempt to automatically log
the user in to the FTP server (see netrc(4tcp)).
Toggle passive mode. When passive mode is turned on, the ftp
client host sends a PASV request to the ftp server when it
attempts to establish a connection for data transfer (see
ftpd(1Mtcp)). The ftp server does a passive open on some random
port and sends the port number back to the ftp client. Using
this port number, the ftp client then does an active open to
the ftp server to establish the connection.
Passive mode is typically used on clients with firewalls, where
the firewalls are configured to disallow incoming calls to
random port numbers. By default, passive mode is turned off.
When passive mode is off, the ftp client host sends a PORT
request to the ftp server when it attempts to establish a
connection for data transfer (see sendport).
Toggle interactive prompting. Interactive prompting occurs
during multiple file transfers to allow the user to selectively
retrieve or store files. If prompting is turned off (default is
on), any mget or mput will transfer all files, and any mdelete
will delete all files.
Execute an ftp command on a secondary control connection. This
command allows simultaneous connection to two remote FTP
servers for transferring files between the two servers. The
first proxy command should be an open, to establish the
secondary control connection. The command proxy ? displays the
other ftp commands executable on the secondary connection. The
following commands behave differently when prefaced by proxy:
open will not define new macros during the auto-login process,
close will not erase existing macro definitions, get and mget
transfer files from the host on the primary control connection
to the host on the secondary control connection, and put, mput,
and 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 PASV request by the server on the secondary control
connection (see passive).
put local-file [ remote-file ]
Store a local file on the remote machine. If remote-file is
left unspecified, the local file name is used after processing
according to any ntrans or nmap settings in naming the remote
file. File transfer uses the current settings for type, format,
mode, and structure.
Print the name of the current directory on the remote machine.
A synonym for bye.
quote arg1 arg2 ...
The arguments specified are sent, verbatim, to the remote FTP
recv remote-file [ local-file ]
A synonym for get.
Retrieve a file restarting at the end of the local-file.
rename [ from ] [ to ]
Rename the file from on the remote machine, to the file to.
Clear reply queue. This command re-synchronizes command/reply
sequencing with the remote ftp server. Resynchronization may be
necessary following a violation of the ftp protocol by the
Restart the transfer of a file from a particular byte-count.
rhelp [ command-name ]
Request help from the remote FTP server. If a command-name is
specified it is supplied to the server as well.
rstatus [ file-name ]
With no arguments, show status of remote-machine. If file-name
is specified, show status of file-name on remote machine.
Delete a directory on the remote machine.
Toggle storing of files on the local system with unique
filenames. If a file already exists with a name equal to the
target local filename for a get or 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 filename will be reported. Note that runique will not
affect local files generated from a shell command (see below).
The default value is off.
send local-file [ remote-file ]
A synonym for put.
Toggle the use of PORT requests. By default, ftp attempts to
use a PORT request when establishing a connection for each data
transfer. This helps prevent delays when performing multiple
file transfers. When a ftp client sends a PORT request to a ftp
server, the client tells the server which port it will be
listening on and the server does an active open to establish
the connection. If the PORT request fails, ftp uses the default
data port. When sendport is turned off, no attempt is made to
use PORT requests for each data transfer. This is useful for
FTP implementations which ignore PORT requests but,
incorrectly, indicate that the PORT requests have been
site [ command ]
Get/set site specific information from/on remote machine.
Return size of file-name on remote machine.
Show the current status of ftp.
struct [ struct-name ]
Set the file transfer structure to struct-name. The default and
only supported struct-name is stream
Toggle storing of files on remote machine under unique file
names. The remote FTP server must support the FTP protocol
command STOU for successful completion. The remote server will
report unique name. Default value is off.
Show the type of operating system running on the remote
Set the file transfer type to that needed to talk to TENEX
Toggle packet tracing.
type [ type-name ]
Set the requested file transfer type to type-name. The
type-name argument may be one of ascii, binary (or
equivalently, image), ebcdic, and tenex (for local byte size
8). NOTE: The remote FTP server may not support transfer types
such as ebcdic.
If no type-name is specified, ftp displays the current type.
The default type is binary if a remote system identifies itself
as a UNIX system; otherwise, the default type is ascii.
umask [ mask ]
Set user file-creation mode mask on the remote site. If mask is
omitted, the current value of the mask is printed.
user user-name [ password ] [ account ]
Identify yourself to the remote FTP server. If the password is
not specified and the server requires it, ftp will prompt the
user for it (after disabling local echo). If an account field
is not specified, and the FTP server requires it, the user will
be prompted for it. If an account field is specified, an
account command will be relayed to the remote server after the
login sequence is completed if the remote server did not
require it for logging in. Unless ftp is invoked with
``auto-login'' disabled, this process is done automatically on
initial connection to the FTP server.
Toggle verbose mode. In verbose mode, all responses from the
FTP server are displayed to the user. In addition, if verbose
is on, when a file transfer completes, statistics regarding the
efficiency of the transfer are reported. By default, verbose is
Aborting a file transfer
To abort a file transfer, use the terminal interrupt key (usually
<Delete> or <Ctrl-C>). Sending transfers will be immediately halted.
Receiving transfers will be halted by sending a ftp protocol ABORT
command to the remote server, and discarding any further data
received. The speed at which this is accomplished depends upon the
remote server's support for ABORT processing. If the remote server
does not support the ABORT command, an ftp> prompt will not appear
until the remote server has completed sending the requested file.
The terminal interrupt key sequence will be ignored when ftp has
completed any local processing and is awaiting a reply from the remote
server. A long delay in this mode may result from the ABORT processing
described above, or from unexpected behavior by the remote server,
including violations of the ftp protocol. If the delay results from
unexpected remote server behavior, the local ftp program must be
killed by hand.
File naming conventions
Files specified as arguments to ftp commands are processed according
to the following rules.
1. If the file name ``-'' is specified, ftp uses the standard input
for reading (stdin) or the standard output for writing (stdout).
2. If the first character of the file name is ``|'' the remainder of
the argument is interpreted as a shell command. Note that there
must not be any whitespace between the ``|'' and the argument. ftp
forks a shell, using popen(3S) with the argument supplied, and
reads (writes) from stdin (stdout). If the shell command includes
spaces, the argument must be quoted.
3. Failing the above checks, if ``globbing'' is enabled, local file
names are expanded according to the rules used in sh(1) (see the
description of the glob command). If the ftp command expects a
single local file (for example, with put), only the first filename
generated by the ``globbing'' operation is used.
4. For mput commands and put commands with unspecified remote file
names, the remote filename is the local filename, which may be
altered by a ntrans or nmap setting. The resulting filename may
then be altered by the remote server if sunique is on.
5. For mget commands and get commands with unspecified local file
names, the local filename is the remote filename, which may be
altered by a case, ntrans, or nmap setting. The resulting filename
may then be altered if runique is on.
When executing the get command, a remote FTP server may perform
certain archival (such as tar), compression (such as compress), and
decompression (such as uncompress) actions on a remote file depending
on the filename that is specified. Archival allows you to retrieve
entire directory hierarchies using a single get command. Compression
allows you to reduce the number of bytes that are needed to send the
files being retrieved. Note that the configuration of the remote FTP
server controls whether these actions (see ftpd(1Mtcp)) are supported
or not. The request will fail if a directory to be tar'ed contains a
file named .notar.
[If this table is unreadable, a preformatted table follows]
filename.Z filename Decompress filename before transmitting
filename filename.Z Compress filename before transmitting
filename filename.tar Tar filename before transmitting
filename filename.tar.Z Tar and compress filename before transmitting
| Actual | Specified | Action |
|filename.Z||filename||Decompress filename before transmitting|
|filename||filename.Z||Compress filename before transmitting|
|filename||filename.tar||Tar filename before transmitting|
|filename||filename.tar.Z||Tar and compress filename before|
The .netrc file
The .netrc file contains login and initialization information used by
the auto-login process. It resides in the user's home directory. See
netrc(4tcp) for a description of the format of this file.
auto-login tokens file
language-specific message file (See LANG on environ(5)).
ftpd(1Mtcp), netrc(4tcp), tftp(1tcp), tftpd(1Mtcp)
Correct execution of many commands depends upon proper behavior by the
An error in the treatment of carriage returns in the 4.2BSD ascii-mode
transfer code has been corrected. This correction may result in
incorrect transfers of binary files to and from 4.2BSD servers using
the ascii type. Avoid this problem by using the binary file transfer
ftp has been updated to handle files larger than 2GB.
The following examples show how various ftp commands may be used and
Set the file-transfer type to binary:
If the remote FTP server's default file-transfer type is ascii, enter
this command if you need to transfer any file that contains data other
than printable 7-bit ASCII text. Examples are program executable
files, graphics files with formats such as GIF and TIFF, and files
containing 8-bit ASCII characters.
Turn on passive-mode data transfers:
This allows you to transfer data from a remote server if you access it
via a firewall that blocks incoming connections to non-privileged
ports. See RFC 1579 for more information.
Turn off prompting, and retrieve all files whose names end in
``.gif'', printing a ``#'' for every 1KB of data transferred:
mget * .gif
Retrieve a README file and display it on the standard output.
get README -
List the contents of the current directory using the pg pager:
ls . |pg
NOTE: No whitespace is allowed between ``|'' and the argument ``pg''.
Retrieve the contents of a README file and display them using more to
eliminate multiple consecutive blank lines:
get README |"more -s"
Have the remote server compress a file named hoopy before transmitting
it to you:
Have the remote server create a tar archive of the directory hierarchy
under the directory babel and compress it before transmitting it to
Change the local current working directory to /usr/tmp:
Copy the entire directory hierarchy under the directory fish to the
local current working directory:
get fish.tar.Z |"zcat - | tar xvf -"
5 November 1999
� 1999 The Santa Cruz Operation, Inc. All rights reserved.
UnixWare 7 Release 7.1.1 - 5 November 1999
See also ftp(3N)