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dtach(1)		    General Commands Manual		      dtach(1)

       dtach - simple program that emulates the	detach feature of screen.

       dtach -a	_socket_ _options_
       dtach -A	_socket_ _options_ _command..._
       dtach -c	_socket_ _options_ _command..._
       dtach -n	_socket_ _options_ _command..._

       dtach  is  a  program that emulates the detach feature of screen. It is
       designed	to be transparent and un-intrusive; it avoids interpreting the
       input  and  output between attached terminals and the program under its
       control.	Consequently, it works best with full-screen applications such
       as emacs.

       dtach is	intended for users who want the	detach feature of screen with-
       out the other overhead of screen. It is tiny, does  not	use  many  li-
       braries,	and stays out of the way as much as possible.

       A  session  in dtach is a single	instance in which a program is running
       under the control of dtach.  The	 program  is  disassociated  from  the
       original	 terminal,  and	 is thus protected from	your original terminal
       being disconnected for some reason.

       Other instances of dtach	can attach themselves to a particular session.
       Input  and  output  is  copied between the program running in the dtach
       session,	and the	attached terminals.

       dtach avoids interpreting the communication stream between the  program
       and the attached	terminals; it instead relies on	the ability of the at-
       tached terminals	to manage the screen.

       Sessions	are represented	by Unix-domain sockets in the  filesystem.  No
       other  permission  checking  other than the filesystem access checks is
       performed.  dtach creates a master process that	monitors  the  session
       socket, the program, and	any attached terminals.

       dtach  has  several  modes of operation.	It can create a	new session in
       which a program is executed, or it can attach to	an  existing  session.
       The first argument specifies which mode dtach should operate in.

       -a     Attach  to  an  existing	session.  dtach	attaches itself	to the
	      session specified	by _socket_.  After the	attach	is  completed,
	      the  window  size	 of the	current	terminal is sent to the	master
	      process, and a redraw is also requested.

       -A     Attach to	an existing session, or	create a new one.  dtach first
	      tries  to	 attach	to the session specified by _socket_ if	possi-
	      ble. If the attempt to open the socket  fails,  dtach  tries  to
	      create a new session before attaching to it.

       -c     Creates  a  new  session.	 A new session is created in which the
	      specified	program	is executed.  dtach then tries to  attach  it-
	      self to the newly	created	session.

       -n     Creates a	new session, without attaching to it. A	new session is
	      created in which the specified program is	executed.  dtach  does
	      not try to attach	to the newly created session, however, and ex-
	      its instead.

       dtach has a few options that allow you to modify	its behavior. Each at-
       taching process can have	separate settings for these options, which al-
       lows for	some flexibility.

       -e _char_
	      Sets the detach character	to _char_.  When the detach  character
	      is  pressed,  dtach detaches itself from the current session and
	      exits. The process running in the	session	is unaffected  by  the
	      detach. By default, the detach character is set to ^\ (Ctrl-\).

       -E     Disables the detach character.  dtach does not try to scan input
	      from the terminal	for a detach character.	The only way to	detach
	      from the session is then by sending the attaching	process	an ap-
	      propriate	signal.

       -r _method_
	      Sets the redraw method to	_method_.  The valid methods are none,
	      ctrl_l, or winch.

	      none  disables redrawing completely, ctrl_l sends	a Ctrl L char-
	      acter to the program if the terminal is  in  character-at-a-time
	      and  no-echo mode, and winch forces a WINCH signal to be sent to
	      the program.

	      When creating a new session, the specified method	is used	as the
	      default  redraw  method  for  the	session. If not	specified, the
	      ctrl_l method is used.

       -z     Disables processing of the suspend key.	Normally,  dtach  will
	      suspend  itself  when  the suspend key is	pressed. With this op-
	      tion, the	suspend	character is sent to the  session  instead  of
	      being handled by dtach.

       The following example creates a new session that	has the	detach charac-
       ter and suspend processing disabled. A socket is	created	 in  the  /tmp
       directory for the session.

	  $ dtach -c /tmp/foozle -Ez bash

       The following example attaches to the /tmp/foozle session if it exists,
       and if not, creates a new session using /tmp/foozle as the  socket  for
       the  session.  Processing of the	suspend	character is also disabled for
       the attach instance.

	  $ dtach -A /tmp/foozle -z bash

       The following example attaches to the /tmp/foozle  session,  using  the
       winch redraw method to redraw the screen.

	  $ dtach -a /tmp/foozle -r winch

       The following example creates a new session and sets the	default	redraw
       method for the session to the winch redraw method.

	  $ dtach -c /tmp/foozle -r winch bash

       Ned T. Crigler <>.


dtach 0.8			   Jan 2008			      dtach(1)


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