I am using perl to open a pipe to pgnuplot.exe to output plot commands. For example,
open ($PLOT, "|pgnuplot") or die "error: gnuplot not found!";
print $PLOT <<EOPLOT;
set term postscript eps enhanced "Arial" 20
set output "somefile.eps"
## do some plotting here ##
EOPLOT
close $PLOT;
I notice that a window for gnuplot always pops up and grabs the focus of my mouse and keyboard momentarily. This makes it difficult to use the computer while the plot script is running.
Is there any way to stop pgnuplot from opening a window?
Yes, when starting a program in Windows (CreateProcess API) it is possible to request that the main window be hidden or minimized without focus (among other options). But I don't know whether perl provides a easy way to do that.
You might consider using batch operation instead (put your plot commands in a file, then pass the filename to gnuplot).
You can prevent showing child console windows via Win32 module:
use Win32;
Win32::SetChildShowWindow(0);
Related
In Ubuntu gnome-terminal it can be done by doing Ctrl + or Ctrl -
Is there a way to write a python script that when executed would resize the font size of the terminal it is executed from?
I need this in order to display images in terminal with high resolution using timg.
Checking the source (vte and gnome-terminal), looks like there's no way to do this. Other terminals (e.g., xterm) can do this using escape sequences. See XTerm Control Sequences:
OSC Ps ; Pt ST
Set Text Parameters. For colors and font, if Pt is a "?", the
control sequence elicits a response which consists of the con-
trol sequence which would set the corresponding value. The
dtterm control sequences allow you to determine the icon name
and window title.
...
Ps = 5 0 -> Set Font to Pt. These controls may be disabled
using the allowFontOps resource. If Pt begins with a "#",
index in the font menu, relative (if the next character is a
plus or minus sign) or absolute. A number is expected but not
required after the sign (the default is the current entry for
relative, zero for absolute indexing).
vte recognizes the 50, but that (like a lot of other xterm features) is just a stub that doesn't do anything. The xterm sources include a 20-year old script which demonstrates the feature (see fonts.sh).
Rather than using an escape sequence, you might be able to use the wmctrl tool (which could ask the window manager to negotiate with the terminal). Some have done that with other terminals, e.g, terminology (but ultimately using an escape sequence).
vte does have some code which might be accessible from a python script, using g_signal_connect to associate decrease-font-size and increase-font-size signal (see source code). The signal code is what you're using with the keyboard. But how you might determine the object pointer from a script starting outside the terminal emulator isn't clear.
There is no easy way to do this across terminals. Terminals support so called control sequences, which can set a bunch of options, like text color and others, but there is no control sequence for setting the font size. See for example https://en.wikipedia.org/wiki/ANSI_escape_code and https://invisible-island.net/xterm/ctlseqs/ctlseqs.html for what kind of actions are supported.
I am trying to create a program which will have live updates from some data source. And I also want to wait for user input just like a normal terminal. Right now, whenever there is update, I will print the content and print the prompt message for input again which create something like this:
Enter command >
This is a live update message
Enter command >
This is a multi-line li......
......ve update message
Enter command > quit
Bye bye!
The problem is that for every live message I received, I will print it and the "Enter command >" will be displayed again again and again, which is not desired. I want the live update to be update on the main part of the terminal, while the "Enter command >" always stay at the bottom
The closest package I can found on Github is https://github.com/gizak/termui but most of the examples inside is trying to display text, gauge and graphs. So I am not quite sure how to get started.
Is there any package or example of the termui package to achieve this? Thank you.
With github.com/gizak/termui you're heading in the correct direction.
To understand why you can't get that
I want the live update to be update on the main part of the terminal, while the "Enter command >" always stay at the bottom
part sorted out, a little excursion to the history of computing is due. ;-)
The thing is, the mode your teminal emulator¹ works by default originated
in how computers would communicate to the operator in the era which predated
alphanumeric displays — they would print their responses using a line printer. Now think of it: a line printer works like this: it prints whatever is sent to it on a roll of paper. What was output, was output.
The new output always appears physically below the older.
When alphanumeric displays (screens) came into existence they
naturally continued to support this mode:
the line text to be output was rendered at the bottom of the screen
with the text above it scrolled upwards.
That's what you see in your typical terminal emulator all the time when you're working in the command line of a shell (such as bash) running by the emulator window.
This, default, work mode of a terminal is called "canonical" or "cooked".
Then came more advanced displays, for which it was possible to change
individual positions on the screen — identified by their column and
row numbers.
This changed the paradigm of how the information was output: the concept
of a so-called "full-screen application" was born.
Typical examples of them are text editors such as Vim and Emacs.
To support full-screen text output, terminals (and terminal emulators)
were adapted by implementing certain extensions to their protocols.
A full-screen application first requests the terminal to switch into another
mode called "raw", in which the terminal sends most of what is input by the
user directly to the program running on the terminal.
The program handles this input and orders the terminal where and what
to draw.
You can read this good summary
of the distinction between the both modes.
As you are supposedly suspecting by now, to be able to keep some block
of information at a certain fixed place of the terminal's text screen,
you want your program to be a full-screen program and use the terminal's
raw mode and its special commands allowing you to directly modify
text at certain character cells.
Now the problem is that different terminals (and terminal emulators)
have different commands to do that, so there exist libraries to isolate
the programs from these gory details. They rely on the special "terminal
information databases" to figure out what capabilities a terminal has
and how to make it do what the program asks.
See man terminfo for more background.
The most widely known such library (written in C) is called ncurses,
and there exist native solutions for Go with supposedly the most visible
one being github.com/nsf/termbox-go.
The github.com/gizak/termui makes use of termbox-go but for you it might
suffice to use the latter directly.
¹ Chances are very high you're not sitting at
a real hardware terminal
connected to a UNIX® machine but are rather working in a GUI application
such as GNOME Terminal or xterm or Termial.app etc.
These are not "terminals" per se but are rather
terminal emulators —
that is, pieces of software emulating a hardware terminal.
I'm using WaitForString command to pause my script until the desired text appears on screen. However I notice that the screen stops "printing" as soon as that happens. I'd rather wait until the whole screen finishes refreshing.
I suspect that instead of WaitForString("text"), I could use WaitForCursor; when the screen is complete, I can use Get("text").
However, I cannot find any documentation that explains the WaitForCursor command. How would I use it in this case?
Have a read through of this manual for secure-crt and scripting with vbscript
Scripting Essentials (PDF)
I expect you would use the command itself as crt.Screen.WaitForCursor(timeout) although I've never used this software myself so that's just a guess
One small thing that has been bugging me with emacs
When opening a shell within a buffer i do:
M-x shell
So far so good
But if I want to open another shell, I switch to another buffer and:
C-u M-x shell
but this always opens in another window - not the one I am currently in
this is annoying does anyone know how to fix it?
EDIT
I should have added that i have multiple buffers open in multiple split windows, e.g. my frame is split into 3 sections - what i want is the new shell to open in the same section that currently has focus, i.e. the one i am typing in and not an alternate one
I think what happens when I do C-u M-x shell is that the new shell buffer opens in the next window, i.e. the one you would shift to if you hit C-x o. I want it to open in the same window
Emacs runs interactive shells in dedicated buffers. It cannot run a shell in, say, TeX buffer.
M-x shell creates a new shell if there isn't one already, and C-u M-x shell asks you for the name of a new buffer. You can also rename the shell buffer to facilitate multiple shells, see the link above.
EDIT: the new shell buffer is displayed using pop-to-buffer-same-window (in Emacs24).
Your best venue is to add *Shell* to display-buffer-alist - but it is not necessary there.
In Emacs23 the display of the *Shell* buffer is controlled by special-display-function (since *Shell* has a match in special-display-buffer-names or special-display-regexps). Set special-display-function to display-buffer-same-window (or something similar) and you should be golden.
However, the ultimate solution is to upgrade Emacs to v24; since you are on a linux system, it should be straightforward.
You can use following codes to force the "*shell*" buffers display in the same window.
(add-to-list 'display-buffer-alist
'("^\\*shell\\*" . (display-buffer-same-window . nil)))
How does one setup and start using vim in the terminal on OS X?
I want to start writing my C code using vim in the terminal rather than a separate text editor. How does one get started on this?
The basics like: opening, creating, saving files via terminal using vim and writing code using vim. Also, does one compile directly using vim in the terminal?
Get started quickly
You simply type vim into the terminal to open it and start a new file.
You can pass a filename as an option and it will open that file, e.g. vim main.c. You can open multiple files by passing multiple file arguments.
Vim has different modes, unlike most editors you have probably used. You begin in NORMAL mode, which is where you will spend most of your time once you become familiar with vim.
To return to NORMAL mode after changing to a different mode, press Esc. It's a good idea to map your Caps Lock key to Esc, as it's closer and nobody really uses the Caps Lock key.
The first mode to try is INSERT mode, which is entered with a for append after cursor, or i for insert before cursor.
To enter VISUAL mode, where you can select text, use v. There are many other variants of this mode, which you will discover as you learn more about vim.
To save your file, ensure you're in NORMAL mode and then enter the command :w. When you press :, you will see your command appear in the bottom status bar. To save and exit, use :x. To quit without saving, use :q. If you had made a change you wanted to discard, use :q!.
Configure vim to your liking
You can edit your ~/.vimrc file to configure vim to your liking. It's best to look at a few first (here's mine) and then decide which options suits your style.
This is how mine looks:
To get the file explorer on the left, use NERDTree. For the status bar, use vim-airline. Finally, the color scheme is solarized.
Further learning
You can use man vim for some help inside the terminal. Alternatively, run vimtutor which is a good hands-on starting point.
It's a good idea to print out a Vim Cheatsheet and keep it in front of you while you're learning vim.
Run vim from the terminal. For the basics, you're advised to run the command vimtutor.
# On your terminal command line:
$ vim
If you have a specific file to edit, pass it as an argument.
$ vim yourfile.cpp
Likewise, launch the tutorial
$ vimtutor
You can definetely build your code from Vim, that's what the :make command does.
However, you need to go through the basics first : type vimtutor in your terminal and follow the instructions to the end.
After you have completed it a few times, open an existing (non-important) text file and try out all the things you learned from vimtutor: entering/leaving insert mode, undoing changes, quitting/saving, yanking/putting, moving and so on.
For a while you won't be productive at all with Vim and will probably be tempted to go back to your previous IDE/editor. Do that, but keep up with Vim a little bit every day. You'll probably be stopped by very weird and unexpected things but it will happen less and less.
In a few months you'll find yourself hitting o, v and i all the time in every textfield everywhere.
Have fun!
if you want to open all your .cpp files with one command, and have the window split in as many tiles as opened files, you can use:
vim -o $(find name ".cpp")
if you want to include a template in the place you are, you can use:
:r ~/myHeaderTemplate
will import the file "myHeaderTemplate in the place the cursor was before starting the command.
you can conversely select visually some code and save it to a file
select visually,
add w ~/myPartialfile.txt
when you select visualy, after type ":" in order to enter a command, you'll see "'<,'>" appear after the ":"
'<,'>w ~/myfile $
^ if you add "~/myfile" to the command, the selected part of the file will be saved to myfile.
if you're editing a file an want to copy it :
:saveas newFileWithNewName
If you want to learn by reading yourself:
Open MacOS terminal app.
Write this and press enter -> vimtutor
For quit write this and click -> :q