modeline needs to be set for it to work
Note that in order for vim modelines to work, you must have the ‘modeline’ option set, i.e. :set modeline. Do a :help modeline for more info.
Logs | Page 5 of 8
These logs are random snippets of information that have been useful to me in the past. Hopefully they help you too!
const variables in C/C++ and multiple definition errors
If you have defined a variable in a header file and not declared it as const, like so: double e = 2.71; then the compiler will treat it as a separate variabl...
Fixing a corrupted sudoers file
If you accidentally corrupt your /etc/sudoers file (usually by reading it without sudo, incorrectly interpreting that it is empty, and then writing into it w...
Using apt-get behind a proxy
Often what happens is that the proxy settings that are set via the command line are not reflected when executing sudo apt-get update/upgrade. The reason this...
Temporarily redifining macros with gcc
You can save and restore macros by using #pragma push_macro("<macro_name>") and #pragma pop_macro("<macro_name>") respectively! This means that y...
Stage only part of a file in git
In order to add only some lines of a file for committing, use git add -p <filename>. If the file is new, use git add -N <filename>. Look up this ...
xsessionrc and xmodmap
In order to have your xmodmap commands take effect, put them in .xsessionrc, NOT .xinitrc. Take a look at this. Also, man xmodmap for a few examples of remap...
Using ASCII codes in vim
To insert characters with a certain ascii code in vim, use <C-v><code>. For example, <C-v>178 will print the squared symbol. I think only t...
Open binary files in vim
To open binary files in a readable format, use vim -b. A more complex tool is xxd. Look at this link or man xxd for more info.
Vim search register
You can substitute the last search pattern in vim either by omitting the search pattern in the :%s command, or by inserting the contents of the search regist...
np.astype
To convert data types in numpy or scipy use np.astype.
Adobe reader messes up bash completion
Adobe reader messes up bash completion. Delete /etc/bash_completion.d/acroread.sh in order to solve the issue. Why does acroread of all things even need bash...
Circularity of bit shift operators in C
The right and left shift operators are not circular. Source.
Changing user and group IDs in Linux
Changing a user id will only change ownership of files that are in that user’s home directory. Look at this SO question. Also, you might have to change the g...
Linux useradd and adduser
For a first-level reference on how to use these commands, look at this link. After that, man adduser. It is nicer than useradd.