WRITE(1) RISC/os Reference Manual WRITE(1)
NAME
write - write to another user
SYNOPSIS
write user [line]
DESCRIPTION
write copies lines from your terminal to that of another
user. When first called, it sends the message:
Message from yourname (tty??) [ date ]...
to the person you want to talk to. When it has successfully
completed the connection, it also sends two bells to your
own terminal to indicate that what you are typing is being
sent.
The recipient of the message should write back at this
point. Communication continues until an end of file is read
from the terminal, an interrupt is sent, or the recipient
has executed "mesg n". At that point write writes EOT on
the other terminal and exits.
If you want to write to a user who is logged in more than
once, the line argument may be used to indicate which line
or terminal to send to (e.g., term/12); otherwise, the first
writable instance of the user found in /var/adm/utmp is
assumed and the following message posted:
user is logged on more than one place.
You are connected to "terminal".
Other locations are:
terminal
Permission to write may be denied or granted by use of the
mesg command. Writing to others is normally allowed by
default. Certain commands, such as the pr command, disallow
messages in order to prevent interference with their output.
However, if the user has super-user privilege, messages can
be forced onto a write-inhibited terminal.
If the character ! is found at the beginning of a line,
write calls the shell to execute the rest of the line as a
command.
write runs setgid() [see setuid(2)] to the group ID tty, in
order to have write permissions on other user's terminals.
write will detect non-printable characters before sending
them to the user's terminal. Control characters will appear
as a `^' followed by the appropriate ASCII character; char-
acters with the high-order bit set will appear in meta
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WRITE(1) RISC/os Reference Manual WRITE(1)
notation. For example, `\003' is displayed as `^C' and
`\372' as `M-z'.
The following protocol is suggested for using write: when
you first write to another user, wait for them to write back
before starting to send. Each person should end a message
with a distinctive signal (i.e., (o) for ``over'') so that
the other person knows when to reply. The signal (oo) (for
``over and out'') is suggested when conversation is to be
terminated.
INTERNATIONAL FUNCTIONALITY
write can send characters from supplementary code sets.
write uses the locale of the sender to determine printabil-
ity.
FILES
/var/adm/utmp
to find user
/usr/bin/sh to execute !
SEE ALSO
mail(1), mesg(1), pr(1), sh(1), who(1), setuid(2).
DIAGNOSTICS
user is not logged on if the person you
are trying to write
to is not logged on.
Permission denied if the person you
are trying to write
to denies that per-
mission (with mesg).
Warning: cannot respond, set mesg -y if your terminal is
set to mesg n and
the recipient cannot
respond to you.
Can no longer write to user if the recipient has
denied permission
(mesg n) after you
had started writing.
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