NAME¶
write - write to another user
SYNOPSIS¶
write [-ctynsprfSv] [ user [ tty ] ]
ojot [-ltynsprfSv] [ user [ tty ] ]
tel [-clynsprfSv] user [ tty ] [message...]
DESCRIPTION¶
Note: This is "Orville write", an enhanced version of the standard
Unix
write program.
Write copies lines from your terminal to that of another user. When first
called, it sends the message:
Message from your-logname your-tty ...
The recipient of the message should write back at this point. Communication
continues until an end of file is read from the terminal or an interrupt is
sent. At that point,
write writes "EOF (your-logname)" on the
other terminal and exits.
The following protocol is strongly suggested for using
write: when you
first write to another user, wait for him or her to write back before starting
to type your message. Each party should end each message with a distinctive
signal (
o for ``over'' is conventional), indicating that the other may
reply;
oo for ``over and out'' is suggested when conversation is to be
terminated. Avoid typing when it is the other person's turn, as your text will
get all garbled with theirs. Anyway, it's rude.
The
ojot command is a variation of
write which normally sends each
character to the other user as you type it instead of waiting for you to
finish a line before sending anything as write does.
The
tel command sends one line ``telegrams'' and then immediately
disconnects. The message may be given on the command lines (in which case it
is usually best to quote it). If you don't put a message on the command line,
you will be prompted for it. This is usually the preferable way to invoke
tel.
All three commands are actually the same program, and share much of the same
behavior.
Permission to write may be denied or granted by use of the
mesg(1)
command. Your write permissions upon login are installation dependent. If you
write a person who has permissions on, but is currently writing someone else,
you will be warned of the fact and be given a chance to cancel your write
request before interupting the other conversation. If you write a person who
is running a command under
amin(1) you will be warned similarly.
You can always send messages to people who are currently writing to you, even if
there message permissions are off. If you have sent a person a
tel
message, then that person can write or telegram to you for the next 4 minutes,
even if your message permissions are off. This means that you won't be sitting
around wondering why someone won't reply, just because you've forgotten to
turn your permissions on. It also means that if you don't want someone to be
able to talk to you, then you shouldn't talk to them. Root may write anyone.
If you invoke the
write or
ojot command with no user name, they
will write to whatever user is currently writing you. If no one is writing
you, an error message is printed.
If you invoke the
write,
ojot, or
tel command with the user
name '.', they will write again to whoever you wrote to last. If you haven't
written to anyone in this login session, an error message is printed. This is
especially useful when you are exchanging a series of messages back and forth
with
tel.
If you want to write to a user who is logged in more than once, the tty argument
may be used to indicate the appropriate terminal. If the tty argument is not
given, the terminal from which you are being written will be written to, if
there is one. If not, one of the lines you have write permission to will be
chosen. If the tty argument is given, the user name can be given as
"-", in which case it will write to whomever is on that tty, if
anyone is.
On some systems there may be users designated as ``helpers''. If your system has
helpers, then doing ``write help'' will write to some helper who is not busy.
If more than one helper is available, one is selected at random to distribute
the workload. Helpers designate themselves with the
mesg(1) command.
They are considered busy if they are writing someone else, or if they are
running a command under the
amin(1) program.
If the character ! , | , or & is found at the beginning of a line,
write calls the shell to execute the rest of the line as a unix
command. If the command began with a ! the output of the command will be sent
only to your terminal. If it began with a |, output will be sent only to the
other person's terminal. If it began with a & each of you will recieve a
copy of the output. Note that
write expands all strange control
characters before sending them to the other person's terminal, but does not do
so for characters echoed back to your terminal.
Write provides several command line options. Actually, the only
difference between
write,
ojot, and
tel is what default
values they have for these options:
- -c
- Send each character as it is typed. Actually, it will not begin doing so
until after the other party has replied. Also, if you type a line starting
with a ")" then the rest of the current line will be held until
you hit return and the sent (minus the ")"). When this option
used, typing a control-R will reprint the text of the line you are
currently typing, and control-W will erase the last word you typed, even
if your unix system doesn't usually support these. In the ojot
command this is the default.
- -l
- Send no characters until a full line has been entered. In the write
command this is the default.
- -n
- During the duration of this conversation, temporarily turn off your
message permissions, so as not to allow people other than the person being
writen to write you.
- -y
- During the duration of this conversation, temporarily turn on your message
permissions, allowing other people to write you after warning them that
you are writing someone else.
- -p
- Postpone the receipt of telegrams during the duration of the conversation.
All telegram received during the conversation will be saved in your
.lastmesg file, and will be displayed when you are finished. The
huh(1) command can be used in a shell escape to check saved
messages without leaving write.
- -s
- During the duration of this conversation, leave your write permissions
unchanged. This normally the default.
- -r
- This causes write to prompt for the root passwd. If it is given
correctly, you will be able to write anyone, no matter how his message
permissions are set, amd you can override his preference for write
or tel.
- -f
- Disallow piping input through write and disable the '&' and '|'
shell escapes. This is mostly meant to be used on 'options' commands in
the orville.conf file. It has been mostly obsoleted by the 'pipes'
configuration command.
- -t
- Sends a one line message (called a telegram) and then disconnects
immediately. The text of the message may be given on the command line, or,
if it isn't, you will be prompted for it. Though write will attempt to
blank out messages given on the command line so they cannot be seen by
users running w(1) or ps(1), this will not always work, so
secret messages should not be placed on the command line. This is the
default in the tel command.
- -S
- Normally if you send a telegram to someone who has indicated a preference
for writes, you get asked if you want to switch to writing, and vice
versa. The -S flag suppresses this question, and just makes it quietly
fail (unless you are root, in which case it quietly succeeds).
- -v
- print the version number.
The options selected by the writer may in some cases be overridden by the
recipient. You can set your preferences for writes versus telegrams, and for
line mode versus character mode with the
mesg(1) command. If the
recipient has set write/telegram preferences, you will be asked if you want to
use the other if you write him the wrong way. If you invoke
Write with
a
-S flag, then you will not be asked if you want to switch. Only root
can actually override the recipient's preferences. For regular users, if you
decline to switch, the command fails.
If the recipient has set character/line mode preferences, a message will be
printed and you will be forced into his or her prefered mode.
CONFIGURATION¶
The
orville.conf file contains configuration information for Orville
write and the associated utilities. Lines starting with '#' and blank lines
are ignored. Other lines contain the commands listed below:
- answertel <seconds>
- Normally you can send telegrams to a person for four minutes (240 seconds)
after they sent you a telegram, even if their message permissions are off.
This command can be used to set size of that window to other values.
- disconnect [y|n]
- If disconnect is enabled the 'mesg d' and 'mesg N' commands can be used by
the writee to disconnect everyone currently writing them. (See
mesg(1)). It is enabled by default.
- exceptions [y|n]
- If exceptions are enabled the 'mesg ye' and 'mesg ne' commandsa can be
used to limit which particular users can and cannot write you (See
mesg(1)). It is enabled by default.
- fromhost [y|n]
- If this flag is set, then message announcement banners will include the
hostname of the sender's machine (and the reciever's since write does not
allow interhost communications). It is disabled by default.
- helperlist <path>
- If this flag is set, then only people whose logins appear in the given
file may be helpers. Otherwise, anyone may be. It is disabled by
default.
- helpername <name>
- By default you get help by doing 'write help'. If you want to use some
keyword other than 'help', use this command to define it.
- helpers [y|n]
- Can people designate themselves to be helpers, and should 'write help'
work? By default, no.
- log <path>
- What file should logging be done in? If not defined, or if it is defined
and the file does not exist, then no logging will be done.
- loglevel <num>
- How much logging should be done? Level 0 means none. Level 1 means only
log help requests (with information about whether they succeeded or not).
Level 2 means logging a one-line description of each write connection
made. Of course, no logging is done if 'log' is not defined or does not
exist. No content of any write conversation is ever logged. The default is
1.
- nohelp <path>
- If someone does 'write help', but no helpers are found, this file is
displayed. Normally it has information on other places to get help. If not
defined, nothing is printed.
- pipes [y|n]
- If turned off, this disallows piping data through write, so you can't do
escapes. This may be necessary if many users are using write to annoy
other users by sending large chunks of data. It defaults on.
- novicehelp <path>
- If the environment variable NOVICE is defined, then print the contents of
this file before running write. If not defined, nothing is printed.
- options <command-name> -<flags>...
- Set default options for different links to the write program. For example,
if you have the line 'options jot -c' and you make a link to the write
program named 'jot', then jot will default to character mode instead of
line mode. If command-name is '*', then all links (even ones created by
users) get that option.
- wrthist <path>
- This is the full pathname of the 'wrthist' file which maintains
information about user's recent messages. It is used to limit telegram
flooding attacks, and allow replies to telegrams during the four minute
window. By default it is in the same directory as the
- wrttmp <path>
- This is the full pathname of the 'wrttmp' file which maintains information
about user's current state. By default it is in the same directory as
the
AUTHOR¶
Jan Wolter
SEE ALSO¶
mail(1),
mesg(1),
who(1),
huh(1),
finger(1),
amin(1),
helpers(1).