Write (Unix)
{{Short description|Unix command to send messages to another user by writing directly to their terminal}}
{{About|the Unix command|the system call|write (system call)}}
{{Primary sources|date=August 2016}}
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{{Infobox software
| name = write
| logo =
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| caption =
| author = Dennis Ritchie,
Ken Thompson
| developer = AT&T Bell Laboratories
| released = {{Start date and age|1971|11|3}}
| latest release version =
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| operating system = Unix and Unix-like
| platform = Cross-platform
| genre = Command
| license =
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}}
In Unix and Unix-like operating systems, {{mono|write}} is a utility used to send messages to another user by writing a message directly to another user's TTY.{{man|1|write|v7}}
History
The write command was included in the First Edition of the Research Unix operating system.{{cite book|title=Unix Programmer's Manual|date=3 November 1971|publisher=Bell Labs|page=write(1)|edition=1st|url=http://www.bell-labs.com/usr/dmr/www/man14.pdf|access-date=9 July 2016|archive-url=https://web.archive.org/web/20160709075913/http://www.bell-labs.com/usr/dmr/www/man14.pdf|archive-date=9 July 2016}} A similar command appeared in Compatible Time-Sharing System.{{cite book |last=Fetter |first=Mirko |date=2019 |title=New Concepts for Presence and Availability in Ubiquitous and Mobile Computing |url=https://books.google.com/books?id=knqIDwAAQBAJ&dq=%22ctss%22+%22write+command%22&pg=PA38 |publisher=University of Bamberg Press |page=38 |isbn=9783863096236 |quote=The basic concept of sending instantaneously messages to logged in users came with ... CTSS ...}}
Sample usage
The syntax for the write command is:
$ write user [tty]
message
The write session is terminated by sending EOF, which can be done by pressing Ctrl+D. The tty argument is only necessary when a user is logged into more than one terminal.[https://www.mankier.com/1/write write(1) – util-linux man page]
A conversation initiated between two users on the same machine:
$ write root pts/7
test
Will show up to the user on that console as:
Message from root@wiki on pts/8 at 11:19 ...
test
See also
{{Wikibooks|Guide to Unix|Commands}}
References
{{Reflist}}
{{Unix commands}}
Category:Unix user management and support-related utilities