04-06-2005
Originally, pipes were implemented with the file system. Even then, they would be in the buffer cache and flushed to disk only if buffer cache pressure was high. These old pipes were one way only. I don't think any current Unix system still does this. BSD switched to socket based pipes. After System 5 got Streams, it switched to Streams based pipes. Both of these are bidirectional.
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LEARN ABOUT DEBIAN
quickplot_shell
QUICKPLOT_SHELL(1) General Commands Manual QUICKPLOT_SHELL(1)
NAME
quickplot_shell - a remote command line shell for quickplot
SYNOPSIS
Usage: quickplot_shell [PID]|[-h|--help]|[QUICKPLOT_OPTIONS]
DESCRIPTION
Quickplot is an interactive 2D plotter. It's primary focus is to interactively display 2D plots. quickplot_shell connects to a running
Quickplot program. quickplot_shell provides a command line interface for most of the graphical user interfaces that are in the Quickplot
program. quickplot_shell reads and writes to standard input and standard output respectively. When standard input is a tty device quick-
plot_shell enables readline tab completion and history. If you would like to save your Quickplot shell history between sessions just cre-
ate a .quickplot_history in your home directory with a command like `touch ~/.quickplot_history'.
If the argument option PID is not given, quickplot_shell will launch Quickplot as a new process and connect to that new process. In this
case Quickplot will be started with QUICKPLOT_OPTIONS if any are given.
If PID is given, quickplot_shell will connect to a running Quickplot program with process ID PID.
quickplot_shell sets up two named pipes, signals the running Quickplot program and writes commands and reads responses to and from the
pipe. The named pipes will be unlinked as soon as they are connected, and hence will be removed automatically when the two programs are no
longer running.
quickplot_shell, the remote Quickplot shell, acts just like running quickplot --shell, a local Quickplot shell, but quickplot_shell runs as
a separate process and talks to the Quickplot program using pipes, where as quickplot --shell runs one process with both the GUI and the
shell with no pipes. You may connect as number of remote Quickplot shells to a Quickplot program.
-h, --help
display help and exit
SEE ALSO
quickplot(1)
COPYRIGHT
Copyright (C) 1998-2011 Lance Arsenault
Quickplot is free software: you can redistribute it and/or modify it under the terms of the GNU General Public License as published by the
Free Software Foundation, either version 3 of the License, or (at your option) any later version.
Quickplot is distributed in the hope that it will be useful, but WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY
or FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for more details.
You should have received a copy of the GNU General Public License along with Quickplot. If not, see <http://www.gnu.org/licenses/>.
AUTHOR
Lance Arsenault <lanceman@users.sourceforge.net>
Send bug reports or comments to the above address.
For more information, see the Quickplot homepage at
<http://quickplot.sourceforge.net/>.
Quickplot Version 0.10.3: 31 Jan 2012 03:27:29 UTC QUICKPLOT_SHELL(1)