I want to downgrade my kernel version on Ubuntu 16.04.3.
However, when I do 'dpkg -l | grep linux-image', the output is like this:
and when I do 'uname -r', the output is like this:
The problem is that I want to remove 4.15.0.24-generic and downgrade it to 4.13, but cannot find 4.15.0.24 on linux-image list.
How can I solve this?
The simplest way to display your Grub is to press and hold the SHIFT button while booting. Then select Advanced option for Ubuntu and choose your kernel version
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I am running Windows 10 on this laptop and recently was recommend to install grep. Well I did that by installing it with a program called GNUWin32.
For some reason I can't get grep to work. Maybe I'm stupid? I don't know but when I type the grep command in CMD it doesn't recognize it.
Any ideas?
I'm trying to use vi mode in bash. via the .inputrc (on OSX):
set editing-mode vi
In vi insert mode, the right arrow key moves the cursor to the right, but it stops on the last character in the line. If the cursor is past the end of the line, it moves the cursor to the left. So, in sum, the farthest right you can go is to the last character in the line.
$ cd /usr/locl/bin
# Move the cursor to the middle of the line, and fix something there
$ cd /usr/local/bin
# Now move the cursor back to the end, and write a character (/)
$ cd /usr/local/bi/n
As shown above this means you cannot edit the end of the line without going into command mode (and using 'a').
I found an article which seems to indicate the version of readline/bash might be the problem. However I used brew to upgrade bash (GNU bash, version 4.3.42), and even tried to install and link readline (6.3.8), as recommend by that site. But no luck. Its possible the upgrade was done incorrectly.
This means I'm looking for one of the following:
The proper way to upgrade bash and readline in OSX terminal
A way to check the versions of bash/readline that OSX is actually using
Another fix for this bug (somehow passing in the virtualedit=onemore option in the inputrc)
Indications that the latest versions of readline might have re-introduced the bug, and solutions.
Also: if theres a similar thing with editrc
Note: I'm looking to make readline in bash act near identical to the default (for others who periodically use my terminal), but allow me to use vim mode. This means I don't need workarounds, but fixes.
Answer here: https://unix.stackexchange.com/a/222506/198846
Apparently it's a bug in the bash version shipped with OSX (3.2), it's fixed in 4.3 according to that answer. Use bash --version to check your bash version.
To fix, update bash, e.g.
macports: sudo port install bash
brew: brew install bash
Once installed bash --version will show it's updated (assuming standard brew/macports paths at the start of your $PATH)
You then have to change your default login shell (in System Preferences->Users & Groups->right click your user->advanced options->login shell) to the path of the new bash:
(default) macports: /opt/local/bin/bash
(default) brew: /usr/local/bin/bash
Changing the default login shell step is required even if which bash shows the macports/brew one.
All credit to the answer linked above.
Can't you edit .bashrc itself instead to use vi mode? The command set -o vi does it in my case (you are in edit mode initially). Also remove the .inputrc edit as the two may actually interact nefariously afterwards.
I tried sw_vers but it only prints the information to the terminal. I cannot use it, as I have to store it in a variable and then compare.
Based on version I have to move files to appropriate location in file system.
What's the correct way to achieve this?
This is the way to do it:
v=$(sw_vers -productVersion)
echo $v
10.9.3
While Googling for another bash tip, I found this page on .inputrc http://ss64.com/bash/syntax-inputrc.html, which exactly fixed what I was trying to do (put a trailing / on symlinks to directories), but as I read further, I saw that there was a way to skip completed text as well. "Awesome", I said to myself, "this bugs me about twice a week". So, I put that into my .inputrc as well, but it doesn't work, or even seem to recognize what's going on. After logging out, and logging back in, this is what I'm seeing:
$ tail .inputrc
set mark-symlinked-directories on
set skip-completed-text on
$ bash --version
GNU bash, version 3.2.48(1)-release (x86_64-apple-darwin10.0)
Copyright (C) 2007 Free Software Foundation, Inc.
$ bind -V | grep completed
$ bind -V | grep skip
$
That is, bash doesn't seem to recognize it's there at all... Is there something wrong with the version of bash supplied in Mountain Lion? Anything blindingly obvious I've forgotten to do?
skip-completed-text is new to bash version 4.
The: skip-completed-text is only in bash4.
On my Mac:
$ bash --version
GNU bash, version 4.2.37(2)-release (i386-apple-darwin12.1.0)
If you want install some opensource utilities i recommending you using macports (www.macports.org). Installing macports will give you one command called port and with it you can install things dead simply, like:
$ port install bash
will install bash 4 for you.
Bash v4 won't make it to OSX. Might I suggest zsh, which is not GPL3.
I have a long running Perl script and I'd like to let it know (and report) how much memory it is using. I'd like to have this information both on Linux and Windows and if possible on Mac OS X as well.
These Perl modules could help you:
Windows: Win32::Process::Memory
Linux(and maybe Mac OSX): Linux::Smaps
This will show you how:
http://perldoc.perl.org/Devel/Peek.html
Also, http://perldoc.perl.org/perlguts.html
and, man pages for perldebug and perldebguts.
This is a quick and dirty and most of all CPAN-free method. It works on any OS that provides a /proc file system, that is Linux and Unix derivates, including Mac OS X, and also on Cygwin under Windows:
perl -e 'print qx{ grep VmSize /proc/$$/status };'