I’ve searched and read many posts but none actually describe what I would like to do. Using Debian Stretch, I’ve been trying to create a Python 3 program that runs what would otherwise be a typed command with switches at the gnome terminal. This is how it should run:
Double click the created *.py file that contains the code for the program.
The gnome terminal appears and the command/switches appear after the $ and then the program runs. Some of the switches have zeros (0) which seems to present an issue. Example command:
$ ./binary.bin -j 0 -n 1300
Anyone have any ideas on how I should start to write this program? Any suggestions would be helpful. Thank you.
Related
First of all, I'm using Ubuntu 20.04 and Python 3.8.
I would like to run a program that takes command line inputs. I managed to start the program from python with the os.system() command, but after starting the program it is impossible to send the inputs. The program in question is a product interface application that uses the CubeSat Space Protocol (CSP) as a language. However, the inputs used are encoded in a .c file with their corresponding .h header.
In the shell, it looks like this:
starting the program
In python, it looks like this:
import os
os.chdir('/home/augustin/workspaceGS/gs-sw-nanosoft-product-interface-application-2.5.1')
os.system('./waf')
os.system('./build/csp-client -k/dev/ttyUSB1')
os.system('cmp ident') #cmp ident is typically the kind of command that does not work on python
The output is the same as in the shell but without the "cmp ident output", that is to say it's impossible for me to use the csp-client#
As you can probably see, I'm a real beginner trying to be as clear and precise as possible. I can of course try to give more information if needed. Thanks for your help !
It sounds like the pexpect module might be what you're looking for rather than using os.system it's designed for controlling other applications and interacting with them like a human is using them. The documentation for it is available here. But what you want will probably look something like this:
import pexpect
p = pexpect.spawnu("/home/augustin/workspaceGS/gs-sw-nanosoft-product-interface-application-2.5.1/build/csp-client -k/dev/ttyUSB1")
p.expect("csp-client")
p.sendline("cmp indent")
print(p.read())
p.close()
I'll try and give you some hints to get you started - though bear in mind I do not know any of your tools, i.e. waf or csp-client, but hopefully that will not matter.
I'll number my points so you can refer to the steps easily.
Point 1
If waf is a build system, I wouldn't keep running that every time you want to run your csp-client. Just use waf to rebuild when you have changed your code - that should save time.
Point 2
When you change directory to /home/augustin/workspaceGS/gs-sw-nanosoft-product-interface-application-2.5.1 and then run ./build/csp-client you are effectively running:
/home/augustin/workspaceGS/gs-sw-nanosoft-product-interface-application-2.5.1/build/csp-client -k/dev/ttyUSB1
But that is rather annoying, so I would make a symbolic link to that that from /usr/local/bin so that you can run it just with:
csp-client -k/dev/ttyUSB1
So, I would make that symlink with:
ln -s /home/augustin/workspaceGS/gs-sw-nanosoft-product-interface-application-2.5.1/build/csp-client /usr/local/bin/csp-client
You MAY need to put sudo at the start of that command. Once you have that, you should be able to just run:
csp-client -k/dev/ttyUSB1
Point 3
Your Python code doesn't work because every os.system() starts a completely new shell, unrelated to the previous line or shell. And the shell that it starts then exits before your next os.system() command.
As a result, the cmp ident command never goes to the csp-client. You really need to send the cmp ident command on the stdin or "standard input" of csp-client. You can do that in Python, it is described here, but it's not all that easy for a beginner.
Instead of that, if you just have aa few limited commands you need to send, such as "take a picture", I would make and test complete bash scripts in the Terminal, till I got them right and then just call those from Python. So, I would make a bash script in your HOME directory called, say csp-snap and put something like this in it:
#/bin/bash
# Extend PATH so we can find "/usr/local/bin/csp-client"
PATH=$PATH:/usr/local/bin
{
# Tell client to take picture
echo "nanoncam snap"
# Exit csp-client
echo exit
} | csp-client -k/dev/ttyUSB1
Now make that executable (only necessary once) with:
chmod +x $HOME/csp-snap
And then you can test it with:
$HOME/csp-snap
If that works, you can copy the script to /usr/local/bin with:
cp $HOME/csp-snap /usr/local/bin
You may need sudo at the start again.
Then you should be able to take photos from anywhere just with:
csp-snap
Then your Python code becomes easy:
os.system('/usr/local/bin/csp-snap')
With xfce4-terminal (on Manjaro): Running chromium "$(xclip -o)" will open the Chromium web browser and visit the content of the clipboard (which is assumed to be a single URL).
I want a desktop launcher to do exactly this. Creating a new launcher (right click on the desktop > create launcher) with the above command in the command field won't work: Chromium is opened, but the address bar says %24%28xclip%20-o%29.
What is happening? The tiny bit of bash knowledge I have tells me that I need to escape some characters -- which ones? I tried different things like chromium \"$(xclip -o)\" and chromium "\$\(xclip -o\)", which produce similar outcomes, but I can't figure it out.
I found this specification of launcher items, but I seemingly fail to understand it well enough to apply it to my problem. Or am I completely on the wrong track?
Another application would be this: xfce4-screenshooter -f -s "$(date +screenshot_%Y-%m-%d_%T.png)" takes a screenshot and names the resulting file with a time stamp. It works being directly run in the terminal, but not when configured as an application shortcut in the keyboard settings. Analogously, the file is named $(date +screenshot_%Y-%d_%m-%T.png).
Try:
bash -c "chromium $(xclip -o)"
in your command field. That worked for me at least. (Also using Manjaro XFCE)
Sorry if the title is vague, I am fairly new to Linux and I don't really know how else to put it. I am creating a script and when I run it, I got it to run Sage but after it does so, the next command isn't executed. I presume this is because the first couple were in the standard Terminal (bash?) and everything after ./sage isn't -- here's the script:
#!/bin/bash
cd /home/alex/Desktop/sage-7.6
./sage
#I also tried wait ${!} here but it didn't work
notebook("/home/alex/Desktop/sage-7.6/projects/zero forcing.sagenb")
How might I enter the last command in Sage after it opens (assuming it's possible)? Thanks!
Edit: Here's a picture of my problem. Sage runs but I can't get it to execute the notebook() command after it opens.
You need to run notebook() as sage code using the -c option mentioned [ here ]. Try the below code.
#!/bin/bash
/home/alex/Desktop/sage-7.6/sage # You can run the interactive shell directly
# At this point you have completely exited the sage interactive shell
# Presumably you want to run the below 'notebook()' after every interactive shell
# In that case do
/home/alex/Desktop/sage-7.6/sage -c 'notebook("/home/alex/Desktop/sage-7.6/projects/zero forcing.sagenb")'
I think what you really want is just to have one command that launches a notebook with a given name.
It turns out that in many Linux/Unix applications, there is automatic help at the command line. Try
/home/alex/.../sage -n -h
to get some help on the notebook. In particular,
sage -n -h --notebook=sagenb
gives a very, very long list of options, the first of which shows that
sage --notebook=sagenb directory=tp
will give you a new sage notebook server in the directory tp.sagenb.
All this said, I should also point out that the sagenb (sadly) is slowly becoming a legacy project in favor of the Jupyter notebook. In Sage 8.0 a conversion from sagenb to Jupyter will become the default, and even now you can just do
sage --notebook=jupyter --notebook-dir=/home/foo/bar
for that to start up.
I want to execute yum list installed > file.txt and output results to a txt file which is NOT wrapped by X characters. At least, I want to be able to control "width" of this output buffer.
I know that stty columns 250 will set column width of my console window to 250 characters but how do I accomplish this when I redirect output to a file?
This has certainly been asked before but I just could not find an answer...
Edit:
This seems to be a yum thing since ps aux > ps.txt works just fine. With yum, file is limited to only 80 characters so I'm adding yum tag. I have no idea how can yum give different output on screen and on the file while other programs work just fine (also note that I'm a beginner in bash).
I think you have two options.
Edit the yum source (http://yum.baseurl.org/download/3.4/yum-3.4.3.tar.gz). The 80 is hard coded in output.py, line 53.
It's probably doable to make yum believe it is writing to a terminal. Whether -- and if, how -- it is possible to set the number of columns for that fake terminal I am not sure of. One thing that pops up is Linux' unbuffer (cf. Piping data to Linux program which expects a TTY (terminal)). Perhaps a little self written unbuffer-like C wrapper may use a pty and have more control over it; even bash may have an esoteric feature for that.
I stumbled across a hackish way to do this using screen:
screen -L yum --color=never list installed
This will result in a file called screenlog.0 containing the output, and yum will think it is outputting to a TTY with the same width as your current screen.
I am looking for any terminal emulator (if any out there), which will have 2 separate areas for input commands and output area.
Terminal Emulator
Output
more output
more output still...
blah blahh
blaahh blah
words
=================================================
>input here
I tried to search in Google but found nothing useful, also I read somewhere this can be achieved using ncurses library, but I have no idea how this can be done. Also I feel, somebody must have done this before, if anyone has done this kind of thing, please share your solution with me, or anyone who knows how this can be done, then I would be grateful if you can provide me some pointers to achieve this.
You can simulate such behaviour with any terminal, by open two instances of it. At terminal #2, get the current PTS by:
$ tty
/dev/pts/10 # for example
then, on terminal #1 you type:
$ exec &> /dev/pts/10
$ echo you can see this message on terminal \#2
$ echo this is also true for standard error > /dev/stderr