I have a linux installation without X. When I launch a third-part application (i.e. gstreamer) it draws on a portion of the screen, let the users see through the external areas.
I want to "clear" the console so it appears black. Of course the clear command won't work because you still see the prompt.
Might you recommend any way to achieve this?
The environment variable which contains the output displayed by the prompt is named PS1. You can empty this variable when needed.
Don't forget to keep a 'backup' of the value in order to be able to set it back to its old value
Related
I just found out about the possibility of hooks in tmux. Since I'm still very new to the command line (and therefore not used to (say need time to) read through all relevant parts of a manpage) I just quickly wanted to ask here, if it is possible to use bash commands to trigger (e.g. when I use ssh, I want to change the color of my status bar). (Although I fear it is not possible).
If not, what could be a way to achieve what I want? Can I make an alias for the command in question and 'reload' a different .tmux.conf file (in a current session)?
Thanks for your help!
Edit:
For example:
I have two versions of a program where I source different environmental variables via aliases (say progVersionA and progVersionB).
When I have a tmux session running, I would like the current 'sourced' environment shown in the status bar (say "progVersionA"). And as soon as I switch to the other program the status bar should read "progVersionB". So, what I want is, that the status bar changes as soon as I run the alias progVersionB.
I only need to set a color that will only effect a particular directory not globally.
If you are using Bash in a terminal that supports colors and would like to change the default color for text output to the terminal (not specifically the output of ls) while inside this directory, there is one thing you could do.
The PROMPT_COMMAND variable can be set to execute a command just before printing the prompt. You could use that to check for the current directory and change the terminal color (for instance by assigning the PS1 variable with a prompt that contains non-displayable special codes for selecting a color or echoing said special codes).
PROMPT_COMMAND is documented in the Bash manual: https://www.gnu.org/software/bash/manual/bashref.html
As for how to assign colors, you should look that up if interested.
This solution may not be what you are looking for, will probably have side effects, and generally speaking, I am not sure it will be that useful changing terminal colors depending on the current directory. The usual solution is to have a prompt that shows the current directory path (or at least the last portion of the path).
I use something similar to the above to change text color depending on which machine I am executing Bash on, as I use ssh a lot from one machine to another over several terminal windows, and color (on a black background) is a good way to remember what machine any given window is connected to.
I'm looking for a method to check from within my shell script that script specific completion have been initialized by user using complete -F ...
I want this check to print out an advice on how to initialize the completion like:
Warning: Auto completion is not initialized. Please run : source ....; complete -F ...
The problem is that the script,being run in a sub-shell has no information about "complete" environment of the parent shell where user is working.
So complete -p| grep my-script-name never return any result.
User is expected to run "source" and "complete" commands or add them into his .bashrc manually, because we're working on a server where we have no access to the bash completion system directory.
Alternatively if you know a method of initializing(and not only checking) the auto-complete from within the script, I would happily accept it.
The only way your script can have access to such information for the parent shell is if it is included instead of executed as a sub-shell. Rather than instructing your users they can include some configuration, you can design your script so it works whether it is run or included.
Then you can simply inform your users that if they want completion enabled they need to include your script rather than run it as an executable script (with instuctions to use source or . as you wish).
However, in this case, I would be inclined to either add this information in documentation or add it into a banner which is always displayed (but can be disabled with an option switch like -q), rather than support two modes of running the script (since the gain is so small).
Either you want every user to use bash completion (which I don't think is good, for example I prefer to have it turned off), or let users decide themselves, but having them this message printed out on each TABTAB is a threat, don't you think?
I'd put into /etc/bash.bashrc what you think every user should run.
I'm making a command interface for a node server, but I have reached a point that I want it to look better.
I want to have the console so you enter a command at the bottom of the terminal screen, you hit enter, and it adds the reply to the actual command line.
If you have ever run a minecraft bukkit server from the command line, you should know what I'm talking about.
Here's a picture of what I'm talking about if you still don't understand. Imagine this was in terminal, and ignore the scroll bars: http://cl.ly/1K0h1V0r0H3f3U3t3L22
Is there anyway to set the console to look like this without having to make your own program for it or having the screen reprint all the other info to fake that look?
I have not done this, but I believe something similar is possible with very little effort by using Node.js REPL. You can override the eval parameter to provide your own command processing.
It would not have the exact look you are wanting, but it will be an interactive prompt that you can utilize (more similar to a Windows command shell or a Linux shell).
If you want the exact look from your screenshot, I don't believe that there is any Node.js module that will help you. There are some that allow you to use colors in the console, and some basic highlighting (e.g. bold), but nothing that gives you complete control over the console screen.
Problem:
I have an extra set of top and bottom gnome-panels for a second monitor. When I undock my lenovo Thinkpad (T510), the extra top and bottom panels remain, so I have two on top and two on the bottom. I am currently running a RHEL6/Fedora (x86_64) gnome (2.28.2) instance with xmonad (0.9.1-6.1.el6) set as the window manager, using the xmonad extensions to work within gnome.
Tried:
I've used acpi and found a code for docking and undocking, but when I try to utilize a script I found in this blog post, it gets zero for the call to xrandr. The script works when called on its own from the terminal. I've tried calling a separate looping script in its own thread and it keeps getting zero for the value, long after the screen(s) update(s).
I have figured out how to have a script loop every X seconds and check for a file which is touched into existence in the event of the script getting a zero, then performing the necessary change, but I don't like that approach.
Question:
I'm hoping someone knows a place I can drop a call to the referenced script and have my panels come and go as I would expect without needing to initiate the script manually.
Thanks!
Update: I have added a bounty of 50 (max I can do) for an answer.
Ben
I guess one of the problems listed below occures (or both):
1) looks like your xrandr snippet doesn't return proper values because the $DISPLAY environment variable is not set correctly. Acpi handler script normally runs as a user which is not the user running your current X session. That way xrandr just does not know which $DISPLAY to access.
2) if $DISPLAY is set correctly, the acpid user might still not be able to access your running xsession. You might check whether the script will work over acpi handler, if you execute xhost + as the user who is currently runging the current xsession with $DISPLAY specified in your script. This will disable access control for X. You can reenable it with xhost - again.
Check it, I hope it helps or will at least point you in which direction to dig.