I noticed that the bash shell can suggest command line switches for your command.
Just type your command, a dash (-) and type tab. The shell will show you available switches.
For example, try:
andy#andyx:~$ java -
and press tab - Surprise!
The question is:
How do I interface with this feature. I.e., if I write a program that is to be run from the console, what's the API to tell the shell what switches are available?
You have discovered Bash's programmable completion feature.
See:
$ man bash
In particular, the section entitled "READLINE" and subsection "Programmable Completion"
FYI: In Ubuntu and/or Debian the scripts are at /etc/bash_completion.d/
Related
This question already has answers here:
How to open a new tab in GNOME Terminal from command line? [closed]
(10 answers)
Closed 3 years ago.
I actually want to run some commands of the same script on different tabs or terminal because these commands are activating servers and listening to different ports. So they have to be always active. As well, I want to have a reference to the tab or the terminal so that I can later shut them down at the end of the script. Help please.
I tried a simple script test to see if I could find a way for opening other tabs :
tab=" --tab"
options=()
cmds[1]="echo Banana"
cmds[2]="echo Cat"
for i in 1 2; do
options+=($tab -e "bash -c \"${cmds[i]} ; bash\"" )
done
gnome-terminal "${options[#]}"
exit 0
but I get this as a result :
./test.sh
# Option “-e” is deprecated and might be removed in a later version of gnome-terminal.
# Use “-- ” to terminate the options and put the command line to execute after it.
# Option “-e” is deprecated and might be removed in a later version of gnome-terminal.
# Use “-- ” to terminate the options and put the command line to execute after it.
Is there any way to open tabs ? and get a reference to each one so that I can shut down commands related to servers once the treatment is done ?
You could use a programm called tmux. It's a terminal-multiplexer, like screen. With that you can open different sessions and windows (these are like tabs) in the same terminal window. They can be referenced by name or id via script.
It's very probable, that the package manager of your Linux distribution has tmux.
P.S: I have to post an answer instead of a comment as I don't have enough reputation for commenting.
This is what I found for man gnome-terminal ; I think that could help , thanks
gnome-terminal(1) General Commands Manual gnome-terminal(1)
NAME
gnome-terminal — is a terminal emulation application.
SYNOPSIS
gnome-terminal [-e, --command=STRING] [-x, --execute ] [--window-
with-profile=PROFILENAME] [--tab-with-profile=PROFILENAME] [--window-
with-profile-internal-id=PROFILEID] [--tab-with-profile-internal-
id=PROFILEID] [--role=ROLE] [--show-menubar] [--hide-menubar]
[--geometry=GEOMETRY] [--working-directory=DIRNAME] [-?, --help]
DESCRIPTION
GNOME Terminal is a terminal emulation application that you can use to
perform the following actions:
Access a UNIX shell in the GNOME environment.
A shell is a program that interprets and executes the commands that you
type at a command line prompt. When you start GNOME Terminal, the
application starts the default shell that is specified in your system
account. You can switch to a different shell at any time.
OPTIONS
-e, --command=STRING
Execute the argument to this option inside the terminal.
-x, --execute
Execute the remainder of the command line inside the termi‐
nal.
--window-with-profile=PROFILENAME
Open a new window containing a tab with the given profile.
More than one of these options can be provided.
--tab-with-profile=PROFILENAME
Open a tab in the window with the given profile. More than
one of these options can be provided, to open several tabs .
--window-with-profile-internal-id=PROFILEID
Open a new window containing a tab with the given profile ID.
Used internally to save sessions.
I am trying to write a bash script to automate running some commands. However some of these commands should be running in their own terminal tab.
So I use the following in my bash script to open a new tab:
xdotool key ctrl+shift+t
this does the job, but the next commands in my bash script are still executed in the previous terminal tab.
How can I make the new opened terminal tab active and run the next commands in this tab?
What Terminal Emulator are you using? It strongly depends on this.
In general, you could write the commands you want to execute in a shell script and tell your terminal emulator to execute the script once it has started.
Example with xterm:
echo '#!/bin/bash' > /tmp/thescript
echo 'ls -la' >> /tmp/thescript
chmod +x /tmp/thescript
xterm -hold -e /tmp/thescript
EDIT: I just saw that u asked for a way to achieve this with xdotool. So this answer might be invalid. Please tell me if so - then i'll delete it.
How are you using xdotool? It can be done with a chain, for example:
$ xdotool key "ctrl+shift+t"; xdotool type "ls"; xdotool key Return
If all you want is to run the commands in the background / in parallel, without synchronously waiting for each command to complete before the next begins, terminate them with an ampersand & to instruct the shell to do so.
Alternatively, you can execute the commands in their own subshells by surrounding each with parentheses ( ). If they are long running processes or you do not wish to pollute the original shell with their output, you can fork them off and capture their output to file with something like (setsid command 1>/path/to/log &).
If separate tabs is necessary requirement, you can use xdotool to key the switch-to-the-next-tab binding or similar, and then key the commands you must run in that tab.
Instead of sorting out that mess yourself, you could use a script from this answer by Jacob Vlijm, which wraps a windowed approach that uses xdotool and wmctrl to 'send' commands to different terminal windows. The script is written in python 3 but it can easily be rewritten for a shell environment of choice.
A more direct approach involves use of a TIOCSTI ioctl to inject characters into another terminal. According to the tty_ioctl manual page:
NAME
ioctl_tty - ioctls for terminals and serial lines
...
DESCRIPTION
The ioctl(2) call for terminals and serial ports accepts many possible
command arguments.
...
Faking input
TIOCSTI const char *argp
Insert the given byte in the input queue
...
Here are c and perl wrappers, and an example in python as referenced by this answer.
Is it possible to enter mark mode(to mark text in Linux terminal) without mouse. In CMD you can ,alt+space+e+k. Can it be done natively without 3th party programs?
Regardless of your terminal you can enable vi mode for you shell, both bash and zsh support this.
A quick one (without installing third party programs) would be to set -o vi in your shell to enable vi and use the shortcuts
If you don't like it you can always come back to emacs: set -o emacs
Can get the command history by using cursor key (like up arrow key) in TCL shell (tclsh).
I am running tclsh on fedora with linux version 2.6.21.
You want access to the readline library, you can do that with rlwrap:
$ rlwrap tclsh
Useful options are -c for file name completion, and -f to add words from a file to the completion list:
$ rlwrap -cf my_complete_file tclsh
Since you almost always want to use rlwrap, adding a shell alias is useful:
alias tclsh='rlwrap tclsh'
I usually use tkcon which comes with ActiveTcl, or as a separate installation. tkcon has many features, but the one I use the most is the command-line editing aspect.
Another good pure-terminal option is tclsh-wrapper
Link to tclsh-wrapper on github
It provides rich command line editing, history, aliasing, and keyword completion but does not require X11. Documentation for the key mapping is also available.
With bash, I can complete a command with TAB. Normally, it should also complete the command line switches: e.g. when I typed:
java -
it should show me the possibilities. It does not. How can I enable this preview?
See also Surprise! the shell suggests command line switches
Take a look at Extended Bash Completion
You need to have bash_completion installed and then just add . /etc/bash_completion to your .bashrc.
Related: Surprise! the shell suggests command line switches
In the answers to that question there were several links to documentation. You might find what you look for there.
Depending on what Linux flavor you're using, you may want to add a package. For Fedora and related distributions, you need to add the separate package bash-completion to get this to work. I wouldn't be surprised if other distributions had this packaged as an optional 2nd package that you need to add in addition to the bash package.
If you want to create your own custom completions you can look at this post:
https://stackoverflow.com/a/21476506/2649637